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The urban barrier effect is one possible physical mechanism by which the urbanization alters the spatial distribution of cloud‐to‐ground (CG) lightning activity in a city. There is a gap in the preceding research on an urban barrier effect to alter patterns of CG lightning in Beijing, and the urban morphology does not receive enough attention as an important influencing factor. By combining lightning location data, ground meteorological data, and urban morphology datasets, we identify a possible urban barrier effect from the perspective of CG lightning in Beijing during 2010–2017. Analysis of one typical thunderstorm on 13 July 2017 revealed that the barrier effect might result in a bifurcation of low‐level airflow and splitting of the convergence line. A more important finding was the modulation of the barrier effect by the scale and density of the built‐up area, and the numerical simulation experiments further confirmed this potential association. Plain Language Summary: Lightning is a common hazard associated with thunderstorms, which can result in $332 million of property damage annually in the United States and cause more than 1,000 casualties per year in China. Beijing, as one of the first‐tier cities in China, is undergoing a rapid urbanization in both city size and building density. Statistical results of cloud‐to‐ground lightning activity over 8 years showed that there were lots of lightning at the edge of the city, and most lightning seemed to be diverted around the city center. Due to a possible barrier effect, the path of a thunderstorm on 13 July 2017 was obviously altered by the city, also resulting in the change of near‐surface wind field. Except for synoptic forcing, wind speed, and urban heat island, this paper pointed out that the size of a city and its building density could influence whether the barrier effect occurred and how strong it was. Key Points: The strong synoptic forcing, strong wind speed, and weak urban heat island were in favor of the formation of a barrier effect in the built‐up area of BeijingWhen thunderstorms passed over city, the bifurcation of low‐level airflow and splitting of convergence line was a result of the urban barrier effectThe size of a city and its building density might influence the occurrence and strength of a barrier effect [ABSTRACT FROM AUTHOR]

Wintertime precipitation, especially snowstorms, significantly impacts people's lives. However, the current forecast skill of wintertime precipitation is still low. Based on data augmentation (DA) and deep learning, we propose a DABU‐Net which improves the Global Forecast System wintertime precipitation forecast over southeastern China. We build three independent models for the forecast lead times of 24, 48, and 72 hr, respectively. After using DABU‐Net, the mean Root Mean Squared Errors (RMSEs) of the wintertime precipitation at the three lead times are reduced by 19.08%, 25.00%, and 22.37%, respectively. The threat scores (TS) are all significantly increased at the thresholds of 1, 5, 10, 15, and 20 mm day−1 for the three lead times. During heavy precipitation days, the RMSEs are decreased by 14% and TS are increased by 7% at the lead times within 48 hr. Therefore, combining DA and deep learning has great prospects in precipitation forecasting. Plain Language Summary: In this paper, we propose a deep learning‐based method to improve the forecast performance of Global Forecast System wintertime precipitation over southeastern China. Due to the imbalanced distribution of precipitation data, we use data from the three other seasons as an augmented data set for wintertime precipitation to train the deep neural network. The results show that the method can reduce the Root Mean Squared Error and improve the TS, a metric of precipitation forecast performance, of the precipitation. In particular, TS at the threshold of 20 mm day−1 are increased by 69.23%, 90.00%, and 100.00% at lead times of 24, 48, and 72 hr. The proposed method performs well during heavy precipitation days at lead times within 48 hr. Combining data augmentation with deep learning provides a successful approach to predicting precipitation. Key Points: A deep learning model based on data augmentation (DA) is proposed to improve the Global Forecast System wintertime precipitation forecastThe deep learning model improves the heavy precipitation forecast at lead times within 48 hrDA plays a critical role in the heavy precipitation forecast [ABSTRACT FROM AUTHOR]

Large‐scale seepage‐faces occur on small‐slope tidal flats. All previous studies assume that the seepage‐face has only one single exit point. Here we show via numerical simulations of tidally‐influenced groundwater flow that, in a two‐dimensional vertical, homogeneous transect of a tidal flat with gentle beach slope of 1‰, multiple seepage‐faces may occur with at most four unsaturated beach surface segments which separate four seepage‐faces. Salinity‐variation induced density‐dependent flow leads to this complex phenomenon. While the seepage‐faces are the groundwater discharging zones on the beach surface, the unsaturated zones are the recharging zones. The whole aquifer beneath the tidal flat is almost occupied by seawater and forms a wall blocking the horizontal seaward discharge of inland fresh groundwater so that inland freshwater discharges mainly occur near the high tide mark. This is in great contrast with the traditional results that inland freshwater discharge occurs mainly near low tide mark. Plain Language Summary: Tidal flat with very gentle‐slopes distributes extensively around the world, for example, the coastline of Bohai, the Yellow Sea of China, and Willapa bay of USA. Due to small slopes, the intertidal zone can be as wide as several kilometers, leading to large‐scale seepage‐faces (saturated beach surface with groundwater efflux) during ebbing and low tides. All previous studies assume that the seepage‐face has only at most one segment, the upper end of which is the exit point of water table and the other end is the intersection point of seawater and beach surface. Here, we found that in a tidal flat with gentle beach slope of 1‰, multiple seepage‐faces may occur with at most 4 unsaturated beach surface segments which separate 4 seepage‐faces during low and rising tides. The locations of these seepage‐faces and adjacent unsaturated zones are quite dynamic due to the complex, dynamic density‐dependent groundwater flow in the aquifer beneath the tidal flat. Seepage‐faces are kind of complex and important boundary for coastal groundwater flow in order to accurately model the groundwater flow and solute transport in intertidal aquifers, the complex nonlinear boundary conditions on the seepage‐faces should be strictly and accurately implemented. This paper made such an attempt. Key Points: Tidal groundwater flow with strict and explicit seepage‐face boundary conditions were numerically simulatedMultiple seepage‐faces were first found to develop on gentle tidal flat with slope around 1‰Multiple seepage‐faces imply multiple local density‐dependent groundwater‐seawater re‐circulations [ABSTRACT FROM AUTHOR]

Predicting the occurrence of internal solitary‐like waves (ISWs) is important for parameterizing turbulent dissipation. ISWs in the northern South China Sea (SCS) are well understood to mainly originate from the Luzon Strait (LS). They are generally predictable due to their phase‐locked relation with tidal forcing in the LS. However, irregular occurrence of ISWs is noted from our 9‐day moored measurements on the SCS shelf. More energetic ISWs unexpectedly appeared during the neap tide than the spring tide. Their occurrence was related to subtidal shelf flows. The tidal and shelf flows had comparable magnitudes. We thus hypothesize that when the total flow meets critical conditions ISWs are generated locally over irregular seafloor. This hypothesis is supported by numerical experiments and validated by observations. Consequently, local generation of ISWs enhances both the intensity and complexity of internal wave field on the shelf, and thus the unpredictability of ISW occurrence. Plain Language Summary: Internal solitary‐like waves (ISWs) are ubiquitous in the ocean. They can propagate several hundreds of kilometers, and induce strong turbulence and mixing. Revealing generation mechanisms and propagation of ISWs is key to further investigating their influence on the distributions of energy dissipation, heat, nutrients, sediment, and pollutants, as well as the safety of submarine voyages and offshore drilling. In this paper, ISWs in the northern South China Sea (SCS), where the most energetic ISWs in the world's oceans are generated, are studied. It is widely accepted that these ISWs generally originate from the Luzon Strait (LS). They usually have regular occurrence, and are phase‐locked to tidal forcing in the LS. However, we present field measurements showing irregular occurrence of ISWs on the northern shelf of the SCS. This irregular occurrence is in striking contrast to the prominent predictability of ISWs originated from the LS. We reveal that the intermittent nature of the occurrence is due to the local generation of ISWs on the shelf; the coupling of different flow components seems to play a significant role in ISW generation on the shelf. The results reported here are expected to be applicable to other shelf regions of the world's oceans. Key Points: Field measurements documented large numbers of internal solitary‐like waves (ISWs) with irregular occurrence on the northeastern shelf of the South China SeaMore energetic and larger numbers of ISWs are observed during the neap tide than during the spring tide as modulated by shelf flowsISWs are locally generated due to the joint effects of tidal and subtidal shelf flows [ABSTRACT FROM AUTHOR]

The PM2.5 (fine particulate matter with diameter ≤2.5 μm) concentration anomalies over the North China Plain (NCP) in early and late winter sometimes show a subseasonal reversal, which brings a great challenge for precise control of air pollution, and mechanisms are not well understood. This paper reveals the key role of the Barents Sea sea‐ice in this reversal. In early winter, a negative Scandinavian‐like pattern causes an anticyclonic anomaly over Northeast Asia and thus leads to the positive PM2.5 concentration anomaly over the NCP. In addition, anomalous warm advection associated with the positive North Atlantic Oscillation‐like pattern accelerates winter sea‐ice loss in the Barents Sea, especially in late winter, which increases the surface turbulent heating flux. These heating causes a negative Polar/Eurasian‐like pattern that induces a cyclonic anomaly over Northeast Asia and eventually leads to a negative PM2.5 concentration anomaly over the NCP in late winter. Vice versa. Plain Language Summary: In this study, we find that there is a significant seesaw pattern of PM2.5 concentration anomalies over the North China Plain (NCP) in early and late winter. Further results reveal that variations in Barents Sea sea‐ice play a crucial role. More specifically, a negative (positive) Scandinavian‐like pattern in early winter tends to induce an anticyclonic (a cyclonic) anomaly over Northeast Asia. This anticyclonic (cyclonic) anomaly leads to a higher (lower) PM2.5 concentration anomaly over the NCP in early winter. In addition, a North Atlantic Oscillation‐related warm (cold) temperature advection promotes (inhibits) the sea‐ice loss in the Barents Sea, especially in late winter. The Barents Sea‐ice loss (increment) in late winter tends to heat (cool) the lower‐level atmosphere and thus triggers an anticyclonic (a cyclonic) response in the upper troposphere there. The anticyclonic (cyclonic) response in the Barents Sea region as a part of the negative (positive) Polar/Eurasian‐like pattern induces a cyclonic (an anticyclonic) anomaly over Northeast Asia, which leads to a lower (higher) PM2.5 concentration anomaly over the NCP in late winter. These findings could be of great value for the subseasonal predictions of PM2.5 concentrations over the NCP in winter. Key Points: PM2.5 concentration anomaly over the North China Plain shows an visibly subseasonal reversal in early and late winter on interannual scaleThe Scandinavia‐like pattern and Polar/Eurasian‐like pattern are responsible for the seesaw pattern of PM2.5 concentration anomaliesThe sea‐ice variations in the Barents Sea play a key role in modulating such atmospheric circulations [ABSTRACT FROM AUTHOR]

Several experiments and field observations have demonstrated seismic waves‐induced permeability increases. However, a few experiments have revealed significant decreases in the permeability of fractured sandstone after shaking produced by dynamic stresses. In this paper, we analyze the tidal responses of the water level in two wells (Junan and Dingyuan) situated on and near, respectively, the Tan‐Lu fault in China. The results sampled by a single well indicate that seismic waves could both increase and decrease the permeability. In addition, our results indicate that the earthquakes that decreased the permeability in a single well were distributed in certain azimuthal zones. Given the azimuthal distribution of distant earthquakes, the observed permeability decrease could be attributed to the seismic wave‐induced clogging of fractures that compose the flow paths in the shallow crust. Our research contributes to an enhanced overall understanding of the effects of earthquakes on the permeability of the shallow crust. Plain Language Summary: Most hydrological phenomena caused by earthquakes can be explained by permeability changes. Many experiments and field observations have demonstrated coseismic increases in permeability. However, coseismic decreases in permeability have seldom been reported. In this paper, we analyze the tidal responses of the water level in two wells. The results indicate that seismic waves could both increase and decrease the permeability. In addition, we find that the earthquakes that decreased the permeability in a single well were distributed in certain azimuthal zones. Given the azimuthal distribution of distant earthquakes, the observed permeability decrease could be attributed to the seismic wave‐induced clogging of fractures that compose the flow paths in the shallow crust. Furthermore, we discuss the possible process of particle remobilization in a natural fracture network caused by seismic waves, as this process may be used to explain the azimuthal distribution of earthquakes that decreased the permeability. Our research contributes to an enhanced overall understanding of the effects of earthquakes on the crustal permeability. In the future, earthquake‐induced increases and decreases in permeability should be considered when discussing controls on permeability for exploring underground resources of groundwater, geothermal energy, oil and gas, and for safely storing nuclear and toxic waste underground. Key Points: Seismic waves could decrease besides increase the crustal permeabilityDecreases in permeability may depend on the earthquake azimuthThe decrease in the permeability could be attributed to the clogging of fractures [ABSTRACT FROM AUTHOR]

This paper reports that there has been a significant relationship between the quasi‐biennial oscillation (QBO) in zonal wind at 50 hPa in summer and precipitation in August in northern China since the late 1970s. The correlation coefficient between them reaches up to −0.61 during 1979–2018. Associated with the easterly (westerly) phase of the QBO, there is a meridional dipole pattern of zonal wind from the stratosphere to troposphere over the Northwest Pacific in August with the easterly (westerly) anomalies in 25–50°N and westerly (easterly) anomalies in 50–65°N. This meridional zonal‐wind dipole favors the strengthening (weakening) of the tropospheric Japan Sea high in the QBO easterly (westerly) phase, causing an increase (decrease) of the water vapor transportation from the Northwest Pacific to northern China and thus more (less) precipitation in these regions. The finding of this study has import implications for predicting the summer precipitation in northern China in the future. Plain Language Summary: The quasi‐biennial oscillation (QBO) is a periodic phenomenon in the tropical stratosphere. It manifested as an alternation of easterly and westerly winds, with an average period of roughly 28 months. It has great influences on the Earth's surface via different pathways. But the previous studies mainly focused on winter. In this study, we are interested in the QBO's impact on the summer precipitation in Asia‐Pacific region. We find that the QBO does have a remarkable relationship with the August precipitation in northern China since the late 1970s. When the QBO is in its easterly phase, it can induce an easterly wind in 25–50°N and a westerly wind in 50–65°N over the Northwest Pacific from the lower stratosphere to lower troposphere, and causes a higher‐than‐normal high pressure over the Sea of Japan, which favors excessive rainfall to its west. Our study provides a direct evidence for the QBO's impact on the Earth's surface in summer. Meanwhile, it also provides potential ideas and methods for predicting the summer precipitation in northern China in the future. Key Points: The quasi‐biennial oscillation (QBO) at 50 hPa has a significantly negative correlation with summer precipitation in northern China since the late 1970sThe QBO can induce a meridional zonal‐wind dipole over the Northwest Pacific that extends from surface into the stratosphereThe enhanced Japan Sea high excited by the meridional zonal‐wind dipole in easterly QBO phase causes more precipitation in northern China [ABSTRACT FROM AUTHOR]

Extremely persistent heavy rainfall (EPHR) events frequently occur in southern China. The mechanisms underlying their generation and development are not well understood, and this leads to difficulties in accurately forecasting these events. In this paper, hourly precipitation grid data and ERA‐5 reanalysis data are used to examine the relationships between precipitation, ageostrophic winds, and low‐level jets (LLJ). The results suggest that ageostrophic winds in the boundary layer mainly exhibit confrontational and asymptotic convergence, with the former being accompanied by double LLJ, which transport more vapor and provide favorable uplift conditions, thus producing stronger precipitation and wider rainbands. The different cooperated relationships between LLJ and ageostrophic winds play an important role in the development of EPHR events, and greater account needs to be taken of these relationships when forecasting. Plain Language Summary: Coastal extremely persistent heavy rainfall (EPHR), long‐duration heavy rainfall in local coastal area, occurs frequently in Southern China, and this kind of rainfall is usually accompanied by southwesterly in the lower atmosphere, which we call as the southwest low‐level jet. Generally, the occurrence and development of rainfall is accompanied by the convergence of the lower air flow. Since the divergence of the geostrophic wind component of the wind field is zero, the convergence situation is characterized by the ageostrophic wind component, which doesn't satisfy the geostrophic balance. In this type of coastal EPHR accompanied by the Southwest Jet, the ageostrophic wind is mainly manifested in two different convergence situations. One is that the ageostrophic wind presents several opposite branches of directions presenting a confrontational pattern around the rainfall area, and the other is an asymptotic convergence in which two similar wind directions, such as northeasterly and southeasterly, gradually converge to the rain area. The former has stronger lower‐level uplift, greater precipitation and wider rain bands, while the latter is relatively weak. This is an interesting phenomenon, of which the specific mechanisms need to be further studied. Key Points: About 74% of extremely persistent heavy rainfall cases along the coast of southern China are accompanied by southwest jets in the marine boundary layerAgeostrophic winds mainly exhibit confrontational and asymptotic convergence, and the former is accompanied by double low‐level jetsCases of ageostrophic winds with confrontational convergence have stronger precipitation and wider rainband [ABSTRACT FROM AUTHOR]

Coastal offshore currents transport terrestrial materials from coastal areas to continental shelf areas in the upper layer; these currents are regarded as unimportant in winter when wind‐driven onshore currents are dominant. In this paper, both long‐term observations and high‐resolution simulations in the East China Sea reveal unique wintertime offshore currents in the upper layer that are widespread in the 30–70‐m isobath area and even overcome the wind‐driven onshore currents at the 50–70‐m isobaths. The mixed layer instabilities, frontogenesis and turbulent thermal wind, which constitute a mechanism in the generation of submesoscale offshore currents, have a growth rate that is fast enough to compete with the wind‐driven dynamics when the winter monsoon is relatively weak (<10 m/s). The alternation of the weak‐wind and strong‐wind modes during the winter monsoons provides a general condition for the repeated occurrence of remarkable submesoscale cross‐shore transport and carbon sequestration in coastal seas. Plain Language Summary: The mechanism by which wintertime cross‐shore currents occur in coastal seas is re‐examined together with wind‐driven mesoscale currents and submesoscale processes. Submesoscale currents, which is shaped like filaments or eddies with a horizontal scale of approximately O(1) km, have frequently been reported in the upper ocean. These submesoscale currents are dynamically defined by conditions where the relative vertical vorticity equals or exceeds the planetary vorticity, where the Rossby number is O(1). Both long‐term observations and high‐resolution simulations in the East China Sea reveal unique wintertime offshore currents in the upper layer that can prevail over wind‐driven onshore currents. The synoptic winter monsoons provide the general conditions for the repeated occurrence of remarkable submesoscale cross‐shore transport and carbon sequestration in coastal seas. Key Points: Significant wintertime offshore currents that overcome wind‐driven onshore currents are investigated in the East China SeaThe submesoscale dynamics are fast enough to compete with the wind‐driven dynamicsThe synoptic winter monsoon provides a general condition for submesoscale cross‐shore events in coastal seas [ABSTRACT FROM AUTHOR]

Extreme summer precipitation often associated with flash floods has devastating impact on the local economies and livelihood of millions of people over East China. Tracking down the drivers of those extreme events will help to understand their formation mechanisms and to improve forecasts. Here the synoptic patterns associated with summer extreme precipitation events over East China during 1961-2018 have been identified systematically and quantitatively using a circulation clustering method. The results show that regional events over East China are dominated by the Eastern Asian summer monsoon associated Meiyu front, landfalling tropical cyclones and low-pressure vortices. Most sub-regions have seen increasing trends of extreme rainfall events during the past 6 decades with comparable contributions from the two main drivers. There was a decreasing trend over the North China Plain driven by the lowlevel southeasterly winds. Plain Language Summary Closely linked to flash floods, extreme precipitation is one of the high impacts but low probability weather phenomena that challenge modern numerical predictions. However, models are generally more skillful in predicting synoptic weather systems than precipitation itself. Taking East China as an example, this paper demonstrates the links between extreme precipitation events and synoptic weather systems using circulation clustering. Two major weather systems, the Eastern Asian Summer Monsoon and landfalling tropical cyclones are responsible for most extreme precipitation events (about 70%) over East China during the summer season. If models can accurately predict the strength and position of these weather systems, there may be enhanced potential of predicting regional precipitation extremes. Such implications are not regionally limited. [ABSTRACT FROM AUTHOR]

Microseisms generated by storms primarily propagate as surface and P waves. However, there has been only one report of S wave microseisms excited by strong storms in the North Atlantic, not from typhoons in the Pacific. In this paper, we present the first observations for S wave microseisms caused by typhoons in Western Pacific, via analyzing ambient seismic waveform recorded by a large‐aperture seismic array in China. The results show that three super typhoons clearly generated S wave microseisms at periods of 5–10 s. The strength of S wave microseism is found to be correlated with P wave. The excitation mechanism for S wave microseism observed in regions with flat seafloor may be related to the interaction between P waves and sub‐ocean sedimentary structure. Plain Language Summary: Besides causing property damages and life losses, ocean storms can also generate seismic waves named as microseisms, which could also be used as signals for studying interior of the Earth. Microseisms mostly propagate as surface waves and P waves. Yet S waves from storms are only detected in the North Atlantic Ocean shown by previous studies. However, there are no reports of S wave microseism by storms in the Pacific Ocean, though the typhoons there are strong and frequent. In this study, we observe and locate S wave microseisms generated by three super typhoons in Western Pacific by processing continuous ambient seismic waveforms recorded in China. The source regions of P and S waves are located very close to each other in the deep ocean near typhoons. Our results show that observability of S wave microseisms depends on P wave energy, which is controlled by strength of typhoons. It is demonstrated that S wave microseisms not only can be generated in the regions with steep topography but also can be excited in the flat seafloor regions. This work is helpful for understanding the excitation mechanism of the S waves. Key Points: We observed body‐wave (P, SV, and probable SH) microseisms from typhoons in the Western PacificWe found that S wave strength is related to P wave power, which in turn relies on typhoon intensityS wave microseisms could be generated in the regions with flat seafloor or bathymetric gradients [ABSTRACT FROM AUTHOR]

An obvious long‐term drying trend in recent early springs (February–March–April) is observed over southeastern China (SEC). Here, we attribute this drying to the weakened subtropical westerlies and deflected by the Tibetan Plateau (TP). Climatologically, the low‐level southwesterlies at the southeastern margin of the TP, a branch of the upstream subtropical westerly jet deflected by the TP terrain, bring water vapor to SEC and the southerlies move upward over SEC mainly through isentropic gliding mechanism, inducing persistent precipitation in early spring. However, the subtropical westerlies weakened significantly in recent decades due potentially to the decreased Eurasian snow cover. Consequently, an easterly trend appears along the southern margin of the TP with anomalous northeasterlies over SEC. These northeasterlies suppress both moisture supply and upward motions over SEC, and reduce regional early spring precipitation. Our results highlight the interaction between the TP terrain and the weakened subtropical westerlies that leads to the drying SEC. Plain Language Summary: Spring precipitation in southeastern China (SEC) is a major rainband during the pre‐flood season in East Asia, which is significant for agricultural production and social economy. However, in the recent few decades, a robust long‐term drying trend has occurred over SEC in early spring. In this study, we propose a new mechanism for the decreased SEC precipitation and highlight the important influence of the weakened subtropical westerlies and their interaction with the Tibetan Plateau (TP). Deflected by the TP large terrain, the upstream weakened subtropical westerlies induce weakened westerlies and southwesterlies along the southern and southeastern margins of the TP, respectively. As a result, the weakened southwesterlies at the southeastern TP not only reduce the moisture transport downstream, but also suppress the ascending motions over SEC through the isentropic gliding mechanism. Both the water vapor and atmospheric circulation conditions finally induce the drying SEC in recent early springs. Key Points: An early spring drying trend has occurred in southeastern China (SEC), much of this can be attributed to the weakened subtropical westerliesDeflected by the Tibetan Plateau (TP), the weakened subtropical westerlies decelerate downstream westerlies along the TP's southern marginThe decelerated westerlies at the southeastern TP suppress moisture supply and rising motions over SEC, both processes cause the drying SEC [ABSTRACT FROM AUTHOR]

Silver is a highly toxic element for marine organisms. However, its controlling factor in marine sediments remains largely unknown, limiting our understanding of its biogeochemical cycling. Based on a sediment core from the Vietnam upwelling area in the South China Sea, it is found that Ag is significantly enriched in sediments of this area (as high as 0.39 μg/g), and it shows a very similar geochemical behavior to Ca and Sr. Our study supports the theory that Ag could be a marine paleo‐productivity indicator. Burial of Ag over the past 3,200 years shows an abrupt increase at around 1850 CE, in concordance with the global atmospheric CO2 record. It is hypothesized that elevated CO2 and global warming enhance marine productivity in the Vietnam coastal upwelling area, favoring the burial of Ag. Human‐induced global warming thus significantly impacts its biogeochemical cycling. Plain Language Summary: Cycling of elements in Earth systems is fundamental to Earth vitality. Examining biogeochemical cycling of elements is thus important in geoscience research. Global warming in recent time has exerted significant impact on the cycles of some elements, including carbon (C), nitrogen (N), and phosphorus (P). This imposes challenges to the integrity and security of Earth ecosystems. However, little is known about some other bio‐active elements. For example, silver (Ag) is highly toxic to marine organisms, but its occurrence, distribution, and fate under a warming background is largely unknown. We analyzed a marine core from the South China Sea, Western Pacific. It was found that concentrations of Ag in the sediments were pretty high, and its burial rate showed an abrupt increase at around 1850 CE. This is probably associated with increased marine productivity as Earth warmed. This study advances our understanding of the Ag cycle. Key Points: High concentrations of and significant variations in Ag were found in marine sedimentsAg in marine sediments is a marker for ocean paleoproductivityGlobal warming favors the burial of Ag in oceans [ABSTRACT FROM AUTHOR]

Previous theoretical simulations showed the generation of double‐layer structures of E‐region field‐aligned irregularities (FAIs). In this study, we report the double‐layer structures of E‐region FAIs observed by an all‐sky radar at low latitude Ledong (18.4°N, 109°E), China. These FAIs appeared at the altitudes ∼90 and 110 km respectively. Both layers displayed quasi‐periodic patterns with synchronized spatial features, that is, being manifested as spatially separated patches or wavelike structures over similar longitudes at the two layers simultaneously. The neutral wind observations revealed the existence of wind shears at two separated altitudes where the double FAI layers occurred. The two wind shears created two vertically separated sporadic E layers and possibly drove the generation of the double‐layer FAIs via gradient drift instability. The synchronized spatial features of the FAIs at the two layers could be modulated by gravity waves. Plain Language Summary: The E‐region field‐aligned irregularities (FAIs) were observed usually in a form of single layer. Due to the limited field of view of narrow‐beam radars which were traditionally employed for observing ionospheric irregularity, the spatial morphology and evolution of E‐region FAIs in a small region were resolved. Owing to the recently developed capability of all‐sky radars in observing E‐region irregularities, the spatial features of E‐region irregularities over a larger zonal region up to hundreds of kilometers in the horizontal plane can be derived. Further, the spatial features of E‐region irregularities in the vertical direction can be unambiguously determined. Utilizing an all‐sky radar at low latitude Ledong, China, a case of double‐layer structures of E‐region FAIs, which occurred at ∼90 and 110 km altitudes respectively, was observed. The double layers of FAIs spanned a zonal coverage ∼250 km, showing as synchronized spatially separated quasi‐periodic patches or wavelike structures in two layers. Especially, the wavelike structures synchronized in the two layers could provide solid evidence for the crucial role of gravity waves in modulating E‐region irregularities. In combination with the collocated ionosonde Es and neutral wind observations, the physical mechanisms responsible for the generation of the double‐layer E‐region FAIs were discussed. Key Points: Double layer structures of E‐region field‐aligned irregularity (FAI) were observed at low latitude by an all‐sky radarBoth layers of FAIs were quasi‐periodic type and synchronously manifested as spatially separated patches or wavelike structuresThe double‐layer FAIs were likely generated by wind shear driven gradient drift instability and modulated by gravity waves [ABSTRACT FROM AUTHOR]

Mg/Ca ratio in stalagmites primarily serves as an indicator of past hydrological conditions rather than temperature variations. Here, we present an Mg/Ca ratio record in a stalagmite from northern China, spanning ice age termination II. A unique finding is that Mg/Ca ratio shows a moderately strong positive correlation with cave air temperature obtained from clumped isotopes data in the same stalagmite. The stable hydrogeochemistry of source water and high temperature sensitivity of Mg partition coefficient plausibly explain this temperature dependence. Furthermore, we establish an Mg/Ca‐temperature calibration for stalagmites from mid‐latitudes, encompassing a temperature range between ∼2 and ∼15°C, where Mg/Ca = 14.221 × e0.073×T (R2 = 0.40). Applying this function to Mg/Ca ratio from similar stalagmites could tentatively provide a quantitative regional temperature record over millennial and centennial timescales. This research highlights Mg/Ca ratio in stalagmites as a potential palaeo‐temperature proxy and introduces, for the first time, a tentative Mg/Ca‐temperature calibration function for speleothems. Plain Language Summary: Stalagmite is one type of speleothems that grow from the floor of caves. The geochemical indexes within stalagmites, such as Mg/Ca ratio, can help us to understand the past climate changes. Here, we conducted a study on a stalagmite from northern China during ice age termination II. Traditionally, Mg/Ca ratios in stalagmites have been used to investigate past hydrological conditions. However, we found that Mg/Ca ratio matches the cave air temperature obtained from clumped isotopes data within the same stalagmite. This correlation was explained by the stable chemistry of the source water and the sensitivity of Mg partition coefficient to temperature. We also developed a tentative formula to calculate past temperature from Mg/Ca ratio in similar speleothems. Key Points: A Chinese stalagmite at termination II shows moderately strong positive correlation between Mg/Ca ratio and clumped isotopes‐temperatureStable drip water hydrogeochemistry and high temperature sensitivity of Mg partition coefficient may explain this temperature dependenceWe tentatively establish, for the first time, an Mg/Ca‐temperature calibration function for speleothems [ABSTRACT FROM AUTHOR]

Geothermal fields emit remarkable amounts of mercury (Hg) to the environment. To address the source, fate and geochemical cycling of Hg in geothermal fields, we investigated Hg concentrations and isotopic compositions of hot spring water and fumarole gases from Rehai and Dagejia in SW‐China. Elevated Hg concentrations in fumarole gases (10.0–167 ng m−3) and hot spring water (3.44–84.5 ng L−1) were observed, suggesting that both geothermal fields are of environmental concern. The variation in Δ199Hg (−0.06 to 0.23‰) and Δ200Hg (−0.09 to 0.19‰) in hot spring water supports Hg likely originating from endogenous volcanic degassing and/or rainwater. Negative and nearly zero Δ199Hg in fumarole gases (−0.32 to 0.03‰) supports volcanic degassing and background atmosphere origin. The ranges of δ202Hg in fumarole gases (−0.74 to 0.59‰) and hot spring water (−1.29 to 0.52‰) could reflect limited fluids boiling in geothermal fields. This study, thus, fills an important knowledge gap regarding Hg global cycling. Plain Language Summary: A large amount of mercury (Hg) is emitted into the atmosphere through geothermal activities. A knowledge gap exists regarding the source, fate and geochemical cycling of Hg in geothermal fields. Here, we studied Hg concentrations and isotopic compositions in hot spring water and fumarole gases from two large geothermal fields in SW‐China. Our results support that the two fields received Hg from endogenous volcanic degassing and rainwater. Deep magma chambers acted as heat sources, triggering fluid circulation in geothermal areas and entraining Hg from rainwater into geothermal systems. Key Points: Rehai and Dagejia geothermal fields are likely of local environmental concern regarding Hg emissionMercury isotopic ratios evidence that geothermal fields could receive Hg from endogenous volcanic degassing and rainwaterGeothermal fluid boiling is not common in geothermal fields in SW‐China [ABSTRACT FROM AUTHOR]

Oblique convergence across the northern Qilian Shan is accommodated by sub‐parallel strike‐slip and thrust faults that ruptured simultaneously in the Mw 8 Gulang earthquake in 1927. We investigate the kinematics of fault loading in the northern Qilian Shan and provide insights into the conditions necessary for generating multi‐fault earthquakes. We perform Bayesian inversions for the geometry and creep rate on the fault network. We infer that all of the thrust faults are locked north of the Qilian‐Haiyuan strike‐slip fault and are accumulating elastic strain. Multi‐fault earthquakes may occurr in this fault system because the faults are simultaneously loaded by the same source of deformation and are linked together by locked fault segments. The interseismic velocity field alone can not contain the location or activity of individual faults visible in the geomorphology, therefore the short‐term geodetic measurements may not reliably indicate the long‐term behavior of the fault system. Plain Language Summary: This study aims to understand the earthquake hazard in the northern Qilian region of China. We use measurements of ground deformation between earthquakes to infer how the faults are being loaded in the region. We find that the ground deformation can be explained by a simple model with a single, slowly creeping fault at depth that loads all of the overlying faults. Large earthquakes that were caused by slip on many different faults at the same time have occurred in this region before. We suggest these so‐called "multi‐fault" earthquakes may occur because all of the faults are being simultaneously loaded by the same source of stress. Key Points: Oblique convergence in the northern Qilian Shan is accommodated by sub‐parallel thrust and strike‐slip faultingThe short‐term geodetic measurements do not constrain the thrust fault kinematics in the northern Qilian Shan over geological timescalesMulti‐fault earthquakes may be common in the region as all of the shallow thrust faults are linked together by locked fault segments [ABSTRACT FROM AUTHOR]

While previous studies have largely focused on anthropogenic warming characterized by surface air temperature, little is known about the behaviors of human‐perceived temperature (HPT), which describe the "feels‐like" equivalent temperature by considering the joint effects of temperature, humidity and/or wind speed. Here we adopted an optimal fingerprinting method to compare seasonal mean HPTs in China with those from simulations conducted with multiple climate models participating in the Coupled Model Intercomparison Project Phase 6. We found clear anthropogenic signals in the observational records of changes in both summer and winter HPTs over the period 1971–2020. Moreover, the anthropogenic greenhouse gas influence was robustly detected, with clear separation from natural and anthropogenic aerosol forcings. The anthropogenic greenhouse gas forcing plays the dominant role (>90%) of human‐perceived warming. Urbanization effects contribute slightly and moderately to the estimated trends in summer and winter HPTs, respectively, in addition to the effects of external forcing. Plain Language Summary: Human influences have been identified in the observed warming quantified by surface air temperature (SAT), but SAT alone is inadequate as a metric for human thermal comfort. Here we focus on human‐perceived temperature (HPT), which describes the "feels‐like" equivalent temperature by considering the joint effects of temperature, humidity, and/or wind speed. We isolate anthropogenic impacts on the observed increase in summer and winter HPTs in China during 1971–2020 by comparing observations with state‐of‐the‐art climate models. Results show that the influence of anthropogenic greenhouse gas is detected, with clear separation from other external forcings such as solar and volcanic activities and anthropogenic aerosols. The human‐induced greenhouse gas increases are also found to explain most (>90%) of the observed human‐perceived warming. Along with the effects of large‐scale anthropogenic forcing, urbanization effects also have a slight to moderate influence on the estimated trends in summer and winter HPTs. Our work is an early attempt to provide quantitative evidence for the physiological impacts of anthropogenic global warming and local urbanization on human beings. Key Points: The warming is quantified by human‐perceived temperature that considers the joint effects of temperature, humidity and/or wind speedHuman influence could be robustly detected in both summer and winter human‐perceived warmingThe observed increase in human‐perceived temperature is mostly attributed to anthropogenic greenhouse gas increases [ABSTRACT FROM AUTHOR]

China's Chang'e-5 (CE-5) mission recently returned samples from a young intermediate-Ti mare unit (Em4/P58, ~1.5 Ga) in Northern Oceanus Procellarum. Rima Sharp, previously mapped as the longest lunar sinuous rille, is the most prominent volcanic feature associated with the landing region. Our analysis shows that Rima Sharp is not a single rille, but instead is composed of two separate rilles (Rima Sharp, originating from the North Vent, and Rima Mairan from the South Vent), meeting at ~40.40°N, 48.38°W. Both vent have characteristics suggesting relatively low magma volatile contents. Rima Mairan and associated lavas (southeast of Em4/P58), embay and are slightly younger than Rima Sharp. Rille formation is largely influenced by pre-existing topography (earlier mare surface, proto-wrinkle ridges, highlands); rilles and deposits experienced post-formation deformation (wrinkle ridges, mare subsidence). CE-5 samples probably originate mainly from Rima Sharp's source vent, but may represent deposits from both rilles. Plain Language Summary A major unanswered question in lunar science is the age and nature of the youngest lunar lava flows, located in the northwest nearside of the Moon but unsampled by Apollo or Luna missions. How long did internal activity and eruption of lavas continue on the Moon? Also very poorly known is the impact flux in the last third of Solar System history. Craters counted on a geologically young lava flow radiometrically dated in the laboratory would answer this question. China's Chang'e-5 (CE-5) mission recently returned samples from just such a young mare unit. But how was this unit emplaced and how does this help us understand the nature of the lava source regions? Rima Sharp, previously thought to be the longest lunar sinuous rille, crosses the young unit. We find that Rima Sharp is actually formed by two rilles, the 320 km-long Rima Sharp and the 150 km-long Rima Mairan, that meet in the middle of the unit. Detailed analysis shows that Rima Sharp was first, forming most of the young basalt unit, followed closely by Rima Mairan, embaying Rima Sharp. Samples returned by CE-5 are most likely to be from the Rima Sharp eruption. [ABSTRACT FROM AUTHOR]

This study unravels the characteristics, mechanisms, and predictability of four consecutive record‐breaking heatwaves hitting North China in June and July 2023. The first three heatwaves primarily influenced the northern part of North China and were accompanied by consistent anticyclonic anomalies in the upper troposphere. The anomalous anticyclone was caused by the British–Baikal corridor teleconnection along the polar front jet, particularly during the second heatwave. In contrast, the fourth heatwave was induced by a distinct low‐pressure system, attributed to the Silk Road pattern along the subtropical jet. The presence of this low‐pressure system and its interaction with atmospheric rivers and local topography led to the foehn wind, further contributing to the rise in surface temperatures. Sub‐seasonal to seasonal models can effectively predict the occurrence of all heatwaves 2–5 days in advance despite underestimating the intensity. However, models exhibit limitations in providing reliable predictions when the lead time exceeds 2 weeks. Plain Language Summary: In the summer of 2023, North China experienced four consecutive extreme high‐temperature events, which are called heatwaves. This study investigates the main factors that cause the four events and shows how well the operational numerical models can predict the heatwaves. The first three heatwaves shared similar circulation, with high‐pressure systems controlling North China. This local circulation anomaly was related to an upstream quasi‐stationary wave train along the polar front jet. The fourth heatwave was associated with a low‐pressure system over North China and an upstream quasi‐stationary wave train along the subtropical jet. Moreover, predictions from operational models demonstrate their capability to forecast the occurrence of high temperatures 2–5 days ahead, with an underestimation in the intensity. However, models are not reliable when it comes to predicting heatwaves 2 weeks in advance. Key Points: North China witnessed record‐breaking heatwaves in June and July 2023, consisting of four sequential synoptic‐scale eventsThe first three and the last heatwaves are controlled by distinct local circulations induced by atmospheric wave trains across EurasiaS2S models capture the heatwave occurrences 2–5 days in advance, but predictive skill notably diminishes beyond 2 weeks [ABSTRACT FROM AUTHOR]

The structural connectivity and kinematic relationship between the Altyn Tagh sinistral strike‐slip fault (ATF) and Qilian Shan fold‐and‐thrust belt along the north Tibetan margin east of 96°E is an important question for tectonicists interested in the evolving active deformation field of Central Asia and associated earthquake hazards of China's Hexi Corridor region. New results from a detailed 130‐km‐long N‐S magnetotelluric (MT) survey from the Qilian Shan to Beishan elucidates the locations and down‐dip orientations of major faults. Importantly, the results indicate that the Heishan‐Jinta'Nanshan fault system roots steeply into the lower crust, is unconnected to the Qilian Shan thrust wedge, and has reactivated the margin of the North China Craton and an older, regional ductile shear belt. The structurally linked ATF‐Heishan‐Jinta'Nanshan system defines a fundamental kinematic boundary in central Asia between the NE directed Qilian Shan thrust belt to the south and the eastwardly extruding Beishan‐Alxa Block to the north. Plain Language Summary: In this study, we present results of a comprehensive electrical resistivity survey conducted in the western Hexi Corridor region of China. The survey reveals significant sub‐surface faults and crustal boundaries, providing insights into the crustal structure between northernmost Tibet (Qilian Shan) and the Beishan. We document how the strike‐slip crustal boundary known as the Altyn Tagh Fault (ATF)‐Heishan‐Jinta'Nanshan system is steep and spatially unconnected to the Qilian Shan east of 98°E. It separates crustal blocks with contrasting motion histories; the southern block experiences compressional deformation, whereas the northern block accommodates extensional and transtensional deformation. Furthermore, the northeast trending ATF bends and converges into the more east‐west‐oriented Heishan‐Jinta'Nanshan system. We propose that this is a result of the Heishan‐Jinta'Nanshan system reactivating an older ductile shear belt and a mechanically weak boundary along the northwestern margin of the Precambrian North China Craton. Our study confirms the significance of inherited crustal structures in localizing continental interior reactivation and associated earthquake hazards. Key Points: A new detailed 3D resistivity model from Northern Tibet to the Southern Beishan clarifies the crustal structure in the NW Hexi CorridorThe Heishan fault system penetrates steeply to the lower crust and is unconnected to the Qilian Shan thrust wedgeCrustal thickening and mountain uplift in Qilian Shan is kinematically separated from eastward Beishan‐Alxa Block extrusion further north [ABSTRACT FROM AUTHOR]

Although carbonates are the primary form of carbon subducted into the mantle, their fate during recycling is debated. Here we report the first coupled high‐precision Zn and Mo isotope data for Cenozoic intraplate basalts from western China. The exceptionally high δ66Zn values (+0.39 to +0.50‰) of these lavas require involvement of recycled carbonates in the mantle source. Variable δ98Mo compositions (−0.39 to +0.27‰) are positively correlated with Mo/Ce, best interpreted as mixing between isotopically light Mo from dehydrated oceanic crust and heavy Mo from recycled carbonates, which is also supported by positive coupling between δ66Zn and δ98Mo. Modeling reveals that involvement of ≤5% carbonate‐bearing oceanic crust fully resolves the observed δ66Zn–δ98Mo mantle heterogeneity probed by intracontinental basalts. Our study demonstrates that combined δ66Zn–δ98Mo data sets for mantle‐derived magmas can track recycled surficial carbonates in Earth's interior, providing a powerful geochemical tool for deep carbon science. Plain Language Summary: Carbon is an element of life and studying its geological cycle is crucial for understanding Earth's evolution including formation of a life‐supporting atmosphere. Here we report the first combined high‐precision Zn and Mo isotope data for Cenozoic intraplate lavas from western China, showing that the basalts record ≤5% carbonate‐bearing oceanic crust components in their mantle source. Our results provide new evidence for surficial carbonates being delivered into the deep upper mantle, which adds to the debate about the deepest extent of the terrestrial carbon cycle. Key Points: First combined zinc (Zn) and molybdenum (Mo) isotope data for mantle‐derived magmas to track the fate of subducted carbonatesZn−Mo isotopic compositions of Cenozoic Tarim basalts suggest surficial carbonates being delivered into the deep upper mantleWe highlight the utility of combined Zn−Mo isotope data as a powerful tool in deep carbon science [ABSTRACT FROM AUTHOR]

Enhanced continental phosphorus input into the ocean has been suggested as a potential trigger for the transient oxygenation events during the mid‐Proterozoic; however, the response of phosphorus cycling to these marine oxygenations remains unclear. Here, we report the changes in phosphorus cycling associated with a ∼1.7 Ga transient oxygenation. Abundant authigenic aluminum phosphate–sulfate mineral svanbergite (SrAl3(PO4) (SO4) (OH)6; 8.02 ± 4.92 wt%) is identified within the ∼1.7 Ga Yunmengshan ironstones from the Xiong'er Basin, North China and other contemporaneous basins. This observation provides new evidence to support the suggestion that early diagenetic aluminum phosphate‐sulfate minerals could have represented a critical sink of marine phosphorus during the Proterozoic. We suggest that atmospheric oxygenation and concomitant changes in porewater redox chemistry may have enhanced the formation of early diagenetic phosphates, leading to a negative feedback on the oceanic phosphorus reservoir and atmospheric oxygen levels. Plain Language Summary: It becomes increasingly clear that multiple transient oxygenation events likely punctuated the low background oxygen world during the mid‐Proterozoic. This may imply that a negative feedback could have inhibited a secular rise in atmospheric oxygen, though the deoxygenation mechanisms remain unclear. Phosphorus (P) availability regulated primary production and therefore controlled the atmospheric oxygen levels during this time, and oxygenation would in turn affect phosphorus cycling. Here we investigate the P cycling during a ca. 1.7 Ga transient oxygenation using mineralogical and geochemical methods. The results show an enhanced phosphorus burial during this transient oxygenation. The elevated phosphorus and sulfate inputs from the enhanced continental weathering and oxygenation may have promoted the formation of aluminum phosphate‐sulfate minerals. This, in turn, reduced the bio‐availability of phosphorus in the marine environment, ultimately limiting marine productivity and leading to a negative feedback on the oxygenation event. This study highlights that phosphorus cycling pathway, which was previously overlooked, may have played a role in the deoxygenation during the intermittent oxygenation events in the mid‐Proterozoic. Key Points: Abundant phosphorus and sulfur precipitation as authigenic svanbergite is associated with the ∼1.7 Ga transient oxygenationThe oxygenation resulted in suboxic and acidic porewater conditions rich in P‐ and sulfate, facilitating the authigenesis of svanbergiteThe enhanced P and S burial as svanbergite represents a significant but overlooked negative feedback during the transient oxygenation [ABSTRACT FROM AUTHOR]

The formation of large igneous provinces (LIPs) has been widely believed to be linked to mantle plume activity. However, how the plume modifies the overlying lithosphere, particularly its compositional structure, remains uncertain. Here, we characterize the deep thermochemical structure beneath the Emeishan LIP (ELIP), which is a well‐known Permian plume‐related LIP in China, by taking a multi‐observable probabilistic inversion. Our results find a clear correlation between the lithospheric composition with the ELIP's concentric zones. We infer that the fertile feature of the lithospheric mantle in the ELIP's inner zone was caused by the plume‐derived fertile magmas which infiltrated into and chemically refertilized the ambient depleted lithosphere. This plume‐modified lithospheric compositional structure is likely to be preserved after the plume event, while the present lithospheric thermal structure has been mainly influenced by the subsequent thermal‐tectonic activity. Our results improve our understanding of the physicochemical interactions between the lithosphere and ancient plume. Plain Language Summary: Gaining insights into the nature of large igneous provinces (LIPs) helps understand mass extinction and climate change in the past, since the outpouring of large accumulations of igneous rocks associated with LIPs could alter ancient climates and environments. Here, we focus on a well‐known plume‐related LIP during the Permian in China, Emeishan LIP (ELIP), to construct its deep thermochemical structure based on a multi‐observable probabilistic inversion method. Our results suggest that the bulk fertile feature (not depleted by melt extraction) of the lithospheric mantle in the vicinity of the ELIP's inner zone was caused by the plume‐derived fertile magmas which infiltrated into the ambient depleted (deficient in minerals extracted by partial melting of the rock) lithospheric mantle and chemically refertilized it by melt‐rock interaction. However, the imaged thermal structure shows a large ongoing asthenospheric upwelling and small‐scale thermal convection, implying that the present‐day lithospheric thickness has been mainly influenced by the subsequent tectonic events. Our results improve the understanding of the physicochemical interactions between the lithosphere and ancient plume and contribute to the knowledge of the nature of LIPs. Key Points: Image the thermochemical structure beneath the Emeishan Large Igneous Province via novel joint inversionsReveal plume refertilization of the lithosphere beneath the Emeishan Large Igneous Province's inner zoneImage complex mantle circulation patterns beneath the Emeishan Large Igneous Province region [ABSTRACT FROM AUTHOR]

The Cenozoic sediments are very thick in the southwest Tarim Basin and very thin in the northwest, but what controls these variations is unclear. Here, we use two‐dimensional thermo‐mechanical models to investigate how the lateral variations in rheological strength and depletion density of cratonic lithosphere mantle affect the cratonic basin deformation. Model results show that the basin basement uplift occurs above either the region with crustal thickening or high depletion in the mantle. A model with a stronger and density‐depleted northern half of cratonic lithosphere mantle in the context of compression matches the differential Cenozoic subsidence and deformation observed in the Tarim Basin well. We propose that a Permian plume led to the lateral heterogeneity of the lithosphere mantle under the Tarim craton, and the modified lithosphere mantle characteristics caused the differential Cenozoic sediment thickness in the Tarim Basin. Plain Language Summary: Tarim Basin is a typical intraplate cratonic basin in northwest China. It is bounded by the West Kunlun Shan to the south and the Tian Shan to the north, respectively. The Cenozoic sediment thickness in the Tarim Basin displays significant lateral variation, which cannot be explained by flexural bending of the Tarim lithosphere under orogenic loads of the West Kunlun Shan and Tian Shan. Recent geophysical data outlined the extent of the Permian plume head, which coincides with the region covered by thinnest Cenozoic sediments. Here, we conduct a series of 2‐D thermo‐mechanical numerical simulations to examine the correlation of the cratonic lithosphere mantle characteristics with cratonic basin's basement geometry. Model results show that a craton with a stronger and density‐depleted northern half of lithosphere mantle in the context of compression matches well with the south‐north differential Cenozoic subsidence and deformation in the Tarim Basin. Accordingly, we suggest that the differential Cenozoic sediment thickness in the Tarim Basin was likely caused by the Permian plume‐modified lithosphere mantle. Our study indicates that the plume‐modified mantle characteristics play a critical role in the basement deformation of the above sediment basin. Key Points: The strength and depletion density of cratonic lithosphere mantle control the deformation of cratonic lithosphere underlying sediment basinThe differential Cenozoic sediment thickness in the Tarim Basin is related to the heterogeneity of cratonic lithosphere mantleThe lithosphere mantle heterogeneity under the Tarim craton was likely caused by post‐Permian plume‐driven recratonization [ABSTRACT FROM AUTHOR]

Data‐driven methods have been extensively applied to predict atmospheric compositions. Here, we explore the capability of a deep learning (DL) model to make ozone (O3) predictions across continents in China, the United States (US) and Europe. The DL model was trained and validated with surface O3 observations in China and the US in 2015–2018. The DL model was applied to predict hourly surface O3 over three continents in 2015–2022. Compared to baseline simulations using GEOS‐Chem (GC) model, our analysis exhibits mean biases of 2.6 and 4.8 μg/m3 with correlation coefficients of 0.94 and 0.93 (DL); and mean biases of 3.7 and 5.4 μg/m3 with correlation coefficients of 0.95 and 0.92 (GC) in Europe in 2015–2018 and 2019–2022, respectively. The comparable performances between DL and GC indicate the potential of DL to make reliable predictions over spatial and temporal domains where a wealth of local observations for training is not available. Plain Language Summary: Machine learning techniques have been extensively applied in the field of atmospheric science. It provides an efficient way of integrating data and predicting atmospheric compositions. Here, we explore the capability of a deep learning (DL) model to make ozone (O3) predictions across continents in China, the United States (US) and Europe. The DL model was trained and validated with surface O3 observations in China and the US in 2015–2018. We then applied the DL model to predict surface O3 concentrations in China, the US and Europe in 2015–2022. Our analysis exhibits comparable performances between DL and chemical transport models for surface O3 predictions in Europe. This indicates the potential of DL models to extend predictions across spatial and temporal domains. Key Points: Deep learning exhibits acceptable capabilities of spatial and temporal extrapolations for surface O3 predictionsComparable performances between deep learning and GEOS‐Chem models with respect to independent O3 observationsGood performance of deep learning for rapid hourly O3 predictions [ABSTRACT FROM AUTHOR]

Using a clustering algorithm based on cloud‐to‐ground (CG) lighting data, 72,974 thunderstorms were identified and tracked in the middle reaches of the Yangtze River Basin from May to September of 2016–2020. Thunderstorms predominantly occur in the southeast region and move to the northeast at a speed of 16–64 km/hr. Most thunderstorms have short durations (98.3%, ≤3 hr) and low CG flash frequencies (90.0%, ≤64). Thunderstorms with longer durations are mainly triggered near the mountains and tend to occur (end) earlier (later) in the afternoon (evening). The peak composite reflectivity (CR) corresponding to CG flashes from all thunderstorms is 50 dBZ. Approximately 70% (20%) of CG flashes occur in convective (stratiform) areas. The first CG flash of a thunderstorm tends to occur in convective areas with a higher CR than that of the last CG flash. The average and maximum CRs of CG flashes increase significantly with thunderstorm duration. Plain Language Summary: Thunderstorms are known as a type of weather system that is typically accompanied by the presence of lighting and other hazardous weather (high winds, heavy rain, hail and tornadoes). Cloud‐to‐ground (CG) lighting produced by thunderstorms is a highly dangerous weather phenomenon that occurs between a thundercloud and the ground and often causes wildfires, explosions and severe damage to buildings. The middle reaches of the Yangtze River Basin in China are a transition zone between plateaus and plains, with dense urban agglomerations, rivers and lakes. However, thunderstorm activity in such complex underlying surfaces is poorly understood. Based on ground‐based radar and lightning observations, the statistical characteristics of thunderstorm activity in this region during the warm seasons (May to September) of 2016–2020 are analyzed using a lightning clustering method. The CG lighting number, area and displacement of thunderstorms increase with thunderstorm duration. Thunderstorms that last longer are mostly triggered near the mountains and often start earlier in the afternoon and end later in the evening. In addition, CG lighting produced by thunderstorms is associated with high radar echo intensity. These findings are useful for improving the nowcasting of lightning and other hazardous weather caused by thunderstorms. Key Points: The cloud‐to‐ground (CG) flash number, area, displacement, etc., of thunderstorms based on lightning data change with increasing thunderstorm durationThunderstorms with longer durations, mostly triggered near the mountains, occur earlier in the afternoon and end later in the eveningRadar echo characteristics of CG flashes from thunderstorms with different durations show certain regularities [ABSTRACT FROM AUTHOR]

The reliable Subseasonal‐to‐Seasonal (S2S) forecast of precipitation, particularly extreme precipitation, is critical for disaster prevention and mitigation, which however remains a great challenge for mission agencies and research communities. In this study, a deep learning method based on U‐Net with additional atmospheric factor forecasts included is proposed to improve S2S quantitative forecasts of summer precipitation over Southern China. The weighted loss function integrated by mean square error and threat score is introduced to capture extreme precipitation more precisely. Generally, the U‐Net model shows promising results in both general statistics and extreme events. Predictor importance analyses show that the U‐Net forecast skills at the 1‐week lead time mainly arise from synchronous precipitation forecasts, but the contributions made by atmospheric factor forecasts rise rapidly with increasing lead times. Therefore, the channel combining numerical weather prediction model and deep learning framework is demonstrated promising in S2S precipitation forecasts. Plain Language Summary: The Subseasonal‐to‐Seasonal (S2S) forecast of precipitation, in particular of the extreme precipitation events, from 2 weeks to a season in advance is challenging despite increasing social demand and scientific interest for accurate and dependable predictions. In this study, the U‐Net based deep learning method is employed with additional atmospheric variable forecasts (e.g., wind and specific humidity at multiple levels) included to correct the S2S forecasts of summer precipitation derived from a numerical weather prediction model over Southern China. It is demonstrated that the U‐Net improves the forecast performance in both general statistics and extreme events and shows a pronounced superiority to the traditional statistical postprocessing method. Thus, combining numerical models and deep learning is very promising in subseasonal precipitation forecasts and can also be applied to the routine forecast of other atmospheric and ocean phenomena in the future. Key Points: The Subseasonal‐to‐Seasonal prediction of summer precipitation over southern China is improved with a U‐Net based deep learning methodThe U‐Net demonstrated promising performance in both general statistics and extreme events and shows superiority to the quantile mapping benchmarkThe model skills arise from precipitation itself at the early stage, while atmospheric factors play important roles at longer lead times [ABSTRACT FROM AUTHOR]

Determination of the optimal parameter values in numerical weather prediction (NWP) models has a significant impact on predictions. Here, we propose a knee point‐based multiobjective optimization (KMO) method to find an optimal solution of the NWP model parameters. We apply it to optimize the Weather Research and Forecasting (WRF) model's summer precipitation and temperature simulations for the Greater Beijing area. The results showed that it required fewer than 125 samples (i.e., 25 times the number of dimensions of the parameter space) to obtain the WRF model's optimal parameter values. The optimal parameters determined by KMO outperform the default parameters in WRF simulations for summer precipitation and temperature prediction in the Greater Beijing area, across all periods (calibration, validation, and testing). Additionally, clear physical interpretations are provided to explain why the optimal parameters lead to improved precipitation and temperature forecasting. Overall, the proposed method is effective and efficient to improve NWP. Plain Language Summary: Numerical weather prediction (NWP) models are highly parameterized and have numerous parameters with uncertain values. The inherent uncertainty in these parameters has the potential to impact the precision of weather predictions. However, the parameter estimation of the NWP model is difficult because (a) there are many meteorological variables to tune, and every parameter value must ensure that the simulation of all meteorological variables is acceptable; (b) an NWP model run is computational expensive, and traditional parameter estimation methods usually require many model evaluations. Here, we propose a multiobjective optimization (i.e., knee point‐based multiobjective optimization [KMO]) method to find an optimal solution of the NWP model parameters (i.e., expensive multiobjective optimization problem) by performing only a few expensive model evaluations. We apply it to optimize the Weather Research and Forecasting model's summer precipitation and temperature simulations for the Greater Beijing Area in China. Numerical results showed that the simulation accuracy for precipitation and temperature were improved, across all periods (calibration, validation, and testing). Additionally, clear physical interpretations are provided to explain why the optimal parameters lead to improved precipitation and temperature forecasting. Overall, the KMO method improves NWP by tuning the model parameters to match predictions with observations. Key Points: A knee point‐based multiobjective optimization (KMO) method was proposed for numerical weather prediction (NWP)Optimal parameter set can be found by running the NWP model 25 times the number of dimensions of the parameter spaceThe optimal parameters determined by KMO outperform the default parameters, across all periods (calibration, validation, and testing) [ABSTRACT FROM AUTHOR]

Archeological evidence from loess sediments from Shangchen on the southeastern Chinese Loess Plateau indicates a suspension of hominin occupation around the time of the early mid‐Pleistocene climate transition, prompting a re‐assessment of climate‐vegetation‐hominin interactions. Loess deposits with in situ lithic records cover the period of hominin occupation and reveal four distinct climate‐vegetation periods (2.1–1.8, 1.8–1.26, 1.26–0.9, and 0.9–0.6 Ma). Major oscillations in climate superimposed upon an aridification trend and an expansion of C4 herbaceous vegetation from about 1.26 Ma may have driven early humans to move to more hospitable locations in the region. Comparison with the record at Nihewan indicates that large‐scale climate oscillations induced disparate hominin responses due to distinctive local environmental conditions. Plain Language Summary: A combination of several lines of evidence suggests that changes in climate and their impacts on the availability of food and shelter from around 1.26 million years ago may have driven the dispersal of early humans from the southeastern Chinese Loess Plateau to more hospitable environments elsewhere in the region. Key Points: Pleistocene temperature, rainfall, and C4 plants ratios are quantitatively reconstructed from the Shangchen loess deposits with artifactsHigh climate variability, C4 plants expansion and aridification suspended hominin occupation at Shangchen during the early mid‐Pleistocene climate transitionHominins responded differently to large‐scale climate oscillations depending on distinctive local environmental conditions [ABSTRACT FROM AUTHOR]

Compound drought‐heatwave (CDHW) events threaten ecosystem productivity and are often characterized by low soil moisture (SM) and high vapor pressure deficit (VPD). However, the relative roles of SM and VPD in constraining forest productivity during CDHWs remain controversial. In the summer of 2022, China experienced a record‐breaking CDHW event (DH2022). Here, we applied satellite remote‐sensing data and meteorological data, and machine‐learning techniques to quantify the individual contributions of SM and VPD to forest productivity variations and investigate their interactions during the development of DH2022. The results reveal that SM, rather than VPD, dominates the forest productivity decline during DH2022. We identified a possible critical tipping point of SM below which forest productivity would quickly decline with the decreasing SM. Furthermore, we illuminated the evolution of SM, VPD, evapotranspiration, forest productivity, and their interactions throughout DH2022. Our findings broaden the understanding of forest response to extreme CDHWs at the ecosystem scale. Plain Language Summary: Low soil moisture (SM) and high vapor pressure deficit (VPD) are widely recognized as the dominant drivers of forest productivity decline during compound drought‐heatwave (CDHW) events. In the summer of 2022, a record‐breaking CDHW (DH2022) struck China. In this study, we decoupled the respective impacts of SM and VPD in determining forest productivity decline during DH2022. We found that during DH2022, SM, rather than VPD, is the dominant driver of forest productivity decline, and once SM decreases below a certain threshold, forest productivity would decline sharply. We illuminated the evolution of SM, VPD, evapotranspiration, forest productivity, and their interactions throughout DH2022. Our findings promote the understanding of forest response to extreme CDHWs at the ecosystem scale and thus potentially improve terrestrial ecosystem models' ability to evaluate and predict the impacts of CDHWs. Key Points: Soil moisture (SM), rather than vapor pressure deficit, dominates the forest productivity decline in the 2022 China compound drought‐heatwave eventForest productivity would decline sharply once SM drops below a certain threshold during extreme compound drought‐heatwave eventsEvolution of the 2022 China compound drought‐heatwave event and its impacts on forests were illuminated [ABSTRACT FROM AUTHOR]

Previous research has extensively explored the "stilling" and "reversal" phenomena in annual near‐surface wind speed (NSWS). However, the variations in the strengths of these phenomena between different months remain unclear. Here the monthly changes in observed NSWS from 769 stations across China during 1979–2020 were analyzed. The analysis reveals a consistent decline in NSWS that ceased around 2011, followed by an increasing trend detected in all months except March, where a distinct hiatus is observed. The hiatus in March NSWS is primarily attributed to a significant reduction in NSWS over North and Northwest China. This reduction can be linked to the southward shift of the East Asian subtropical jet (EASJ), which resulted in a decreased meridional temperature gradient and weakened transient eddy activities across northern China. These findings emphasize the importance of considering changes in the EASJ to gain a comprehensive understanding of NSWS changes at regional scale. Plain Language Summary: Understanding how near‐surface wind has changed and identifying the factors driving these changes are crucial. This can help in developing adaptation strategies to increase society's resilience to possible future climate, such as understanding the future revenues of electricity production from wind farms. By analyzing wind observations from 769 stations across China since 1979, we confirmed a general decrease (stilling) that ceased around 2011, followed by a general significant increasing tendency (reversal) in all months but March. Indeed, March's wind series after 2011 showed a pause (i.e., hiatus) from the 1979–2011 slowdown. This hiatus was mainly caused by the general wind reduction across northern China since 2011, which differs from the wind increase observed in other regions. The slowdown in March from 2011 to 2020 is related to the southward shift of East Asian subtropical jet streams, which are fast‐flowing, narrow, and meandering air currents in the upper atmosphere. Jet streams play an important role in shaping both upper and lower air circulation and influence surface wind by transporting high and low‐pressure systems. Key Points: March near‐surface wind speed (NSWS) over China experienced a hiatus after 2011, distinct from other monthsThe observed hiatus in March NSWS was primarily caused by a significant reduction in NSWS over North and Northwest ChinaA southward shift of the East Asian subtropical jet may have contributed to the detected hiatus [ABSTRACT FROM AUTHOR]

This study analyzes microphysical signatures relevant to the short‐cycle lightning activity in the inner core of Typhoon Hato (2017) before landfall in China. Observations reveal that the lightning bursts were accompanied by enhanced inner‐core convection with a behavior cycle of about 3 hr. The coupling between wavenumber‐2 vortex Rossby waves (VRWs) and shear‐forced convective asymmetries resulted in a local updraft enhancement. Furthermore, supercooled liquid water droplets invigorated a striking enhancement of graupel via riming immediately above the freezing level, further enhancing charge separation and lightning generation outside the eyewall. Furthermore, when similar phase‐locking was associated with other propagating VRWs, graupel and updraft volumes were significantly boosted, leading to short‐cycle lightning outbreaks in the inner core. Plain Language Summary: Lightning behavior is one of the well‐defined indicators of convection within the Tropical cyclone (TC) circulation. Before the landfall of Typhoon Hato (2017), we found short‐cycle lightning outbreaks in the inner core of this typhoon. The interaction between the internal structures of the storm and changes in wind speed and direction with height could strikingly reinforce convection, thereby favorable for the short‐cycle electrification enhancement. This scenario is distinct from diurnal lightning bursts within TCs, which were found in previous studies. The diurnal lightning activity is thermodynamically governed by radiation, while vortex‐environment interactions in the inner core of Hato dynamically force the short‐cycle lightning outbreaks revealed here. Therefore, the findings presented in this case study suggest that interactions between the internal structures of a TC and the environment warrant an adequate focus in the short‐range forecasting of inner‐core convection in landfalling TCs. Key Points: Short‐cycle lightning outbreaks were found in the inner core of Typhoon Hato (2017)Interactions between vortex Rossby waves and the shear‐induced convective enhancement likely led to the quasi‐periodic lightning behaviorStrengthened updrafts and the significant growth of graupel enhanced the charge separation and lightning outbreaks [ABSTRACT FROM AUTHOR]

Mars' surface is characterized by a weathered layer of regolith and exposed rock exposures that are the results of long‐term geological processes. The Mars Rover Penetrating Radar (RoPeR) on board the Zhurong rover of China's first Mars mission (Tianwen‐1) has been investigating the fine structure and dielectric properties of the martian regolith in the southern Utopia Planitia. The permittivity of the regolith within 5 m of the landing zone is 3.6−2.0+3.1 ${3.6}_{-2.0}^{+3.1}$, and the average loss tangent is 0.0174−0.0053+0.0053 ${0.0174}_{-0.0053}^{+0.0053}$. The high lossy parameter suggests the possible cause for the missing subsurface reflectors in the landing region detected by either in‐situ radar or orbiter radars. The permittivity distribution map has been derived to show permittivity varying with depth and location. The high dispersion of both permittivity and loss tangent values along the traverse path indicates relatively heterogeneous material distribution on the landing site compared to an airless body such as the Moon. Plain Language Summary: A layer of regolith covers the surface of Mars, which is the result of geologic processes that occurred over millions to billions of years. Compared to the observations from satellites, the Zhurong rover of China's first Mars mission (Tianwen‐1) had a closer look at the properties of the regolith layer in the explored region within southern Utopia Planitia. There is evidence that the exposed materials might be related to aqueous activities. Local landforms on the surface suggest the possible presence of buried volatiles, like water ice. The radar instrument (RoPeR) on board the rover can expose subsurface structures and the dielectric properties of the regolith layer at high‐resolution, to assess their composition. The loss tangent results suggest that water ice is not the main component of the local martian regolith at some depth. The scattering distribution of radar profile along the traveling path and heterogeneous subsurface features show more diverse surface processes and weaker space weathering effects on Mars than those on the airless Moon. Key Points: The dielectric properties of martian regolith at the Tianwen‐1 landing site suggest that water ice is not the dominant componentThe radar image and permittivity and loss tangent distribution maps show a high heterogeneity of subsurface materialsCompared to the lunar regolith, the martian regolith shows more diverse surface processes and weaker space weathering effects [ABSTRACT FROM AUTHOR]

The limited availability of long‐term historical dust records has impeded comprehension of the mid‐latitude atmospheric circulation and underlying mechanisms of dust activities in arid Central Asia. We present a well‐dated 2,800‐year peat record from the northeastern Qinghai‐Tibet Plateau and identified the aeolian origin of archived particles by comparing grain‐size distribution and strontium isotope with those of modern dusts. We show that the reconstructed dust input was enhanced during warming periods, which also coincides with the variation of Westerlies, total solar irradiance, and North Atlantic Oscillation. We propose that warming climate may have contributed to a significant impact on the moisture balance and wind strength, and predict that this region may experience more frequent dust activity in the future. These findings contrast with meteorological observations of decreasing dust activities during the last 40 years despite a warming trend, suggesting different effects of natural processes versus anthropogenic impact on global warming. Plain Language Summary: Dust activity in arid regions is not only influenced by atmospheric circulation and regional climate changes, but it can also have significant impacts on human health and the environment of habitats. While modern dust research is relatively accurate, longer‐term records are still essential for a more comprehensive understanding of mechanisms and effects of dust activity scenarios. We have provided a well‐dated 2,800‐year record of dust activity in the northeast of the Qinghai‐Tibet Plateau, the south border of arid Central Asia, mainly by grain‐size and element analysis of the minerals trapped in the alpine peatland from the Qilian Mountains. The results show that intense dust activity is related to the warm and arid climate, consistent with mid‐latitude Westerlies and sea‐air circulation changes. The increased likelihood of dust activity in arid regions, such as northwest China, suggests a correlation with global climate anomalies. Key Points: The aeolian origin of the particles archived in the alpine peat was determined by grain size and elemental analysisDust activity increases when climate changes from cold to warmDrought and strong winds caused by the strengthening of solar irradiance and Westerlies led to more dust input in the northwest China [ABSTRACT FROM AUTHOR]

The simulation skill of the perturbed parameter ensemble (PPE) of HadGEM3‐GC3.05 on the mean climate pattern of the Asian summer monsoon (ASM) is evaluated in this study. The sensitivities of the model bias to the perturbed parameters are investigated based on metrics. The results show that the PPE mean (PPE‐20M) could effectively capture the general ASM precipitation and wind patterns, with a correlation coefficient of 0.78. PPE‐20M mainly shows positive precipitation biases over the tropical western Pacific, southern slope of the Tibetan Plateau, Indochina Peninsula, and South China and negative precipitation biases over the Indian continent and Bay of Bengal. The magnitude of the precipitation biases is more sensitive than its pattern to the variation of the perturbed parameters. Four parameters (ent_fac_dp, qlmin, ps_cloud‐ph, and psm) are found to be crucial for simulating the ASM precipitation intensity, and their combined effects are related to the simulated precipitation biases. Plain Language Summary: The simulation of the Asian summer monsoon (ASM) has attracted much attention in recent decades. However, state‐of‐the‐art coupled models still show similar systematic biases when simulating monsoon precipitation from CMIP3 to CMIP6. Recently, a perturbed parameter ensemble (PPE) method has been applied in the development of HadGEM3‐GC3.05 with the aim of improving the overall simulation skill of the coupled model. The PPE can also be used to understand the related physical processes in the model simulations. Thus, in this study, we aim to evaluate the simulation skills of PPE on the mean climate distributions of ASM. Four parameters were found to be the most critical in the precipitation simulations, which could be potential tunable parameters to reduce the biases of precipitation intensity over the monsoon regions. This study provides possible pathways to reduce model bias that could benefit the model development community. Key Points: The perturbed parameter ensemble mean captures the climate pattern of the Asian summer monsoon (ASM) but mainly overestimates precipitation over the western PacificFour parameters (ent_fac_dp, qlmin, ps_cloud‐ph, and psm) are crucial for simulating ASM precipitation in coupled runThe joint effect of these parameters, especially the deep entrainment amplitude, are dominant control for the bias in the western Pacific [ABSTRACT FROM AUTHOR]

The snow physical parameters are closely related to the sizes, shapes, and chemical composition of light‐absorbing particles (LAPs). By utilizing a computer‐controlled scanning electron microscope software called IntelliSEM‐EPASTM, we first report the measured size‐resolved concentration of soot, dust, and fly ash particles in fresh (wet) and aged (dry deposition) snow samples collected at an industrial city in China during and after a snowfall at intervals of 6–8 days. Due to wet scavenging by seasonal snow, soot and dust particles in snow are absorbed by 69.7% and 30.3% at wavelengths of 550 nm, lowering snow albedo by 0.0089 and 0.0039, respectively. Soot particle size increases slightly during dry deposition, whereas size‐resolved mineral dust does not undergo a significant shift in particle size. These results indicate the essentiality to involve the effects of accurate size and composition of in‐snow LAPs for a better assessment of snow light absorption and reflectance. Plain Language Summary: A field survey was undertaken to collect freshly fallen (1) and aged surface (15) snow samples at 1‐day intervals in the center of Changchun city, China, which is surrounded by heavy industrial emission sources. We used an advanced computer‐controlled scanning electron microscope to determine particle size and number distributions of three major light‐absorbing particle types with diameters of 0.2–10 μm in seasonal snow, namely soot, dust, and fly ash. Soot and dust particles deposited in various ice‐grain sizes via wet and dry deposition were also examined in terms of their contributions to light absorption and snow albedo reduction. We report here a first attempt to detect a combination of log‐normal soot, dust, and fly ash in seasonal snow, as well as their potential effects on the reduction of snow albedo. Key Points: Computer‐controlled scanning electron microscopy was used to identify size‐resolved light‐absorbing particles in surface snowSoot particle size increases slightly during dry deposition, whereas size‐resolved dust doesn't undergo a significant shift in particle sizeSize‐resolved soot and dust are critical factors in the determination of snow light absorption and albedo [ABSTRACT FROM AUTHOR]

The Jehol and Yanliao biotas of northern China, two world‐class Lagerstätten with abundant biomass and biodiversity, provide critical clues to Mesozoic terrestrial ecosystems. Their evolution is a response to the destruction of the North China craton. However, the impetus for the rapid bloom of the biotas remains a mystery. Mesozoic large‐scale volcanic‐sedimentary strata in northern China are rich in terrestrial organisms. Statistical analyses show that volcanic nutrient element delivery, biomass, and biodiversity in these stratigraphic sequences increase synchronously, while harmful elements have the opposite change with them. These observations reveal the coevolutionary relationship between volcanism and terrestrial biotas. The increased nutrient element supply and inhibited harmful element delivery to terrestrial ecosystems from the voluminous volcanic products, produced under the geodynamic regime of paleo‐Pacific subduction and cratonic destruction, could create a conducive environment for the biodiversity and high prosperity of Mesozoic terrestrial biotas. Plain Language Summary: The weathering of volcanic products can quickly provide material supply for ecosystems, including nutrient and harmful elements. The availability of these elements in volcanic‐sedimentary sequences can provide key evidence for the intrinsic relations between volcanism and terrestrial biological evolution. Through statistically‐based big data analyses, we determine the changes in nutrient/harmful element delivery, biomass, and vertebrate and entomic diversity of the Mesozoic fossil‐bearing volcanic‐sedimentary strata in northern China. Excluding the interference of pyroclastic flows on the fossil records, the results reveal the significant contributions of elevated volcanic nutrient supply to the flourishing of the Jehol and Yanliao biotas. Meanwhile, the inhibited release of harmful elements has limited impacts on the biotas. This study opens a new path for multidisciplinary investigations to explore the feedback relationship among regional tectonics, volcanism, and terrestrial biotas. Key Points: Mesozoic terrestrial biotas in northern China coevolved with volcanism during the paleo‐Pacific subduction and cratonic destructionThe increasing supply of volcanic nutrients promoted the flourishing of the Jehol and Yanliao biotasInhibited volcanic toxic delivery facilitated the rapid bloom of the terrestrial biotas [ABSTRACT FROM AUTHOR]

Deciphering dust outbreak frequency in inland Asia during the late Cenozoic is important for predicting future hydroclimate in the arid parts of China. Here, we present an eolian sedimentary sequence in the southern Junggar Basin over the past 3.5 Ma, Northwestern China. Our data provide a minimum age of 3.5 Ma for the Gurbantunggut Desert. Rb/Sr ratios exhibit prominent 405 Kyr eccentricity cycles throughout our record with weak expression 41 Kyr cycles. We interpret this cyclicity as resulting from a strong impact of the global carbon cycle on western China hydroclimate. By contrast, gamma‐ray intensity data displays significant 100‐ and 41‐Kyr cycles after 2.8 Ma, suggesting important variations of the input of westerly derived dust. Our results demonstrate that Westerly derived moisture supply and dust input into inland Asia respond differently to orbital forcing; they suggest that moisture supply and dust transport by the Westerlies are controlled by different drivers since 3.5 Ma. Plain Language Summary: Little is known about how hydrological changes in desert areas respond to today's high atmospheric CO2 concentrations. Hydroclimatic archives from these areas are critical to understand (and possibly forecast) future hydrological changes at local and regional scales. Herein, we present paleomagnetic, gamma‐ray intensity and Rb/Sr data over the past 3.5 Ma from an eolian sedimentary sequence in the southern Junggar Basin, Northwestern China. Our results provide a minimum age of 3.5 Ma for the Gurbantunggut Desert; they show that humidity and Westerlies strength variations in inland Asia follow different cyclicity during the Quaternary, indicating that moisture supply by the Westerlies since 3.5 Ma is not directly impacted by wind strength. Our results show that Junggar hydroclimate is likely poorly sensitive to changes in Westerlies strength, despite their role as moisture conveyor, raising questions about the main control on moisture supply in inland Asia. Key Points: Rb/Sr ratios exhibit prominent 405 Kyr eccentricity cycles throughout our recordGR data displays significant 100‐ and 41‐Kyr cycles after 2.8 MaMoisture supply by westerlies is not directly impacted by wind strength since at least 3.5 Ma [ABSTRACT FROM AUTHOR]

The Arxan volcanic group is one of the largest active volcanic fields in China. Its last eruption occurred ∼2,000 years ago, but it still has a potential of eruption in the future. The spatial distribution and migration channel of its magmatic reservoirs are still unclear. Here we precisely locate microearthquakes and study the detailed 3‐D velocity structure of the volcanic area using a large number of high‐quality P and S wave arrival‐time data recorded at 227 portable seismometers. A swarm of microearthquakes (M < 1.5) related to magmatic activity were recorded, which lasted about 4 days during 13–16 September 2020. Our tomographic results show that 12 Arxan volcanoes share the same magmatic system. The melt fraction of a magma chamber below the Tianchi volcano at ∼0–8 km depths is estimated to be ∼6.1%–8.6% from the seismic velocity reductions. Our results indicate that the Arxan magmatic system is still active at present. Plain Language Summary: The detailed crustal structure and magmatic system beneath the Arxan volcanic field in NE China are still unclear due to the lack of a dense seismic network in the area. Local earthquakes associated with the volcanic activity in this area are all very small, so precise location of the seismic events is a challenge. We deployed a dense portable seismic network in the volcanic area to precisely locate 712 microearthquakes. Then we determine a detailed 3‐D seismic velocity model of the crust beneath the volcanic area. As a result, the spatial distribution and migration channel of magmatic reservoirs in the Arxan volcanic area are revealed for the first time. Key Points: We precisely locate microearthquakes and study 3‐D Vp and Vs crustal structure beneath the Arxan volcanic areaA microearthquake swarm occurred during 13–16 September 2020, reflecting magmatic activity of the Arxan volcanic group12 Arxan volcanoes share the same magmatic system with a melt fraction of ∼6.1%–8.6% [ABSTRACT FROM AUTHOR]

The western segment of the suture zone between the Yangtze and Cathaysia blocks, which is the most important tectonic boundary related to the formation and rifting of south China, is enigmatic and not fully understood due to the sporadic exposure of Precambrian strata and ophiolites. Three‐dimensional electrical resistivity models derived from inversion of magnetotelluric data identified a lithospheric‐scale conductive zone extending northeastwards beneath the Youjiang basin, which was interpreted as the western segment of the suture zone. The high conductivity and coincident high magnetic anomalies closely match the location of Carlin‐type gold deposits, which can be explained by fluids and gold‐bearing sulfide minerals in a fossil suture zone. Inconsistent with the southeast‐dip resolved at the eastern segment of the suture zone (the Jiangshan‐Shaoxing fault) in the earlier study, the slightly north‐dipping geometry at the western suture zone implies the reactivation by northward subduction and closure of the Paleo‐Tethys Ocean. Plain Language Summary: Suture zones are tectonic scars that mark the subduction, collision, and amalgamation of different tectonic units. Imaging suture zones is critical because they are first‐order tectonic boundaries and can play a guiding role in continental rifting and breakup. The suture zone between the Yangtze and Cathaysia blocks is the most important tectonic boundary in south China. While the eastern segment of this suture zone is agreed to be located along the Jiangshan‐Shaoxing fault, the western segment of this suture zone is under debate. This study used magnetotelluric method to image the deep earth structure beneath the western boundary of the Yangtze and Cathaysia blocks. We identified a high‐conductivity zone from the subsurface to a depth of 80 km and interpreted this zone as being caused by fluids and gold‐bearing sulfide minerals in a fossil suture zone. The conductivity pattern observed in this suture zone differs from that in the earlier study about the eastern segment of the suture zone. This implies that the western suture zone has been modified after the initial collision of the two continents, perhaps by northward subduction and closure of the Paleo‐Tethys Ocean. Key Points: Magnetotelluric array data were inverted to obtain the lithospheric resistivity structure in southwestern ChinaThree‐dimensional resistivity model images a Precambrian suture beneath the Youjiang basinThe geometry resolved at the suture zone implies the reactivation by northward subduction and closure of the Paleo‐Tethys Ocean [ABSTRACT FROM AUTHOR]

Since early 2019, the Lunar Penetrating Radar (LPR) onboard Chang'e‐4 (CE‐4)'s Yutu‐2 rover has been gathering data relating to the subsurface structure of the Von Kármán crater within the South Pole‐Aitken Basin (SPA) on the lunar farside. Low‐frequency radar data have the potential of carrying geological information of about 300 m worth of strata below the traversed path. Forty‐two days' data have revealed a bifurcated structure within the layered structure beneath the CE‐4 surveying area for the first time, affecting the overlying reflectors between 90 and 310 m. This study suggests that, based on the morphological characteristics, thickness, depth (timing sequence) and direction of the newly found structure, its origin might be linked to the deposition of ejecta from the Schrödinger impact. The local stratigraphy is interpreted as consisting of distinct geological layers, corresponding to the superposition of ejecta from different impact craters, paleo‐regolith, and basaltic lava flows. Plain Language Summary: A radar (the Lunar Penetrating Radar, or LPR), built to look at the rocks below the surface, is presently traveling across an area of the lunar farside onboard a rover, called Yutu‐2 sent by China to shed some light on the striking difference between the Earth‐facing side of the Moon and its farside. So far, the radar has revealed layered structures interpreted as distinct volcanic flows, thus helping to unravel their history. The rover has been surveying the floor of the Von Kármán crater inside one of the oldest and largest impact structures of the Moon, the South Pole‐Aitken (SPA) Basin. By analyzing 42 lunar days of data, we found a new layer with a hunched upper surface and a relatively flat bottom inserted into a multilayered structure. Based on the morphology, thickness, depth, and direction of the new feature, we argue that its source could represent the ejecta deposition from one of the ancient lunar impact basins: Schrödinger. The subsurface structure revealed by the radar shows a complicated geologic history on the farside including multiple lava eruption events, the deposition of ejecta from different impact craters and weathering layers that develop during the quiescent stage. Key Points: The CH‐1 Lunar Penetrating Radar data of Chang'e‐4 reveals ∼300 m deep subsurface stratigraphy of the lunar farsideA unique bifurcated structure that resembles an ejecta discontinuity affects the overlying and underlying strataThe geologic evolution of the Von Kármán crater and the ejecta layer might be connected to the Schrödinger basin [ABSTRACT FROM AUTHOR]

Both seismic and geodetic data suggested that the ∼120‐km long Weifang segment of the Tanlu fault zone, a large‐scale active strike‐slip system at east China, is a seismic gap with no obvious along‐strike shear motion at surface. Measuring crustal deformation around the segment is crucial to constrain stress/strain buildup and potential seismic risk at the fault. We measured crustal and upper mantle seismic anisotropy using P‐to‐S converted waves at the Moho (Pms) and core‐mantle boundary (SKS) recorded by broadband arrays across the Weifang fault segment. The measured crustal anisotropy inside the fault zone shows a fast direction of ∼NNE, parallel to the fault orientation. Right east to the fault zone, the fast axis rotates by almost 90° to ESE. The crustal anisotropy within the fault zone could be caused by aligned microcracks and foliated minerals due to long‐lasting shear motion inside the fault zone. Plain Language Summary: The Tanlu fault zone (TLFZ) is the most prominent fault system in east China, an area with a large population and economy. One of the most devastating earthquakes in recent history of China, the M8+ Tancheng earthquake occurred in the central segment of this fault. The Weifang segment north to the Tancheng earthquake has little seismicity and is considered as a seismic gap region. Surface Global Positioning System (GPS) data, however, suggested that there is very little present‐day crustal deformation across the North China Plain where the Weifang segment is located. This is also supported by shear‐wave splitting measurements of the core phases (SKS). Therefore, it is unclear whether the seismic gap is due to lack of strain/stress buildup, or the GPS/SKS data have no resolution on crustal deformation. In this study, we deployed a dense seismic array across the segment, and chose a seismic wave, a P‐to‐S converted wave at the crust‐mantle boundary (i.e., the Moho), to measure crustal deformation. The measured seismic property indicates the presence of aligned microcracks and foliated minerals within the fault zone, which suggests significant shear deformation is occurring inside the TLFZ. Key Points: The Weifang segment of the Tanlu fault zone shows a noticeable crustal anisotropy with a fast axis parallel to the NNE oriented faultEast to the fault zone, fast direction rotates rapidly by ∼90° to ESE, parallel to the SKS fast polarization directionThe southeastern part of the study area has a thinned crust with a Vp/Vs ratio measurably lower than a typical cratonic crust [ABSTRACT FROM AUTHOR]

The widespread development of Permian/Triassic boundary microbialites is a key biosedimentary response to the mass extinction event. The microbial communities that precipitated these structures remain, however, poorly resolved. Here, we report abundant columnar microfossils from five Permian‐Triassic successions in South China. Four phases of the microfossil life cycle are recorded: baeocytes, juvenile column, mature column, and baeocyte‐splitting, which are interpreted as Pleurocapsales (cyanobacterial clade that reproduces by multiple fission). The great thickness (up to 13 m) of these microbial deposits and Raman spectrum analysis indicate a strong calcification capacity of the Pleurocapsales. Pronounced peaks of Mg/(Mg + Ca) ratios from microbialite and distinct Mg‐enrichment in microfossils indicate that Pleurocapsales blooms may also have facilitated dolomitization of the microbialites. Common occurrence, strong biomineralization capacity, baffling framework, and the close association with carbonate minerals suggest that Pleurocapsales were key constructors of post‐extinction microbialites. Plain Language Summary: As a biosedimentary response to the end‐Permian mass extinction, the widespread occurrence of microbialites has attracted increasing levels of interests from geologists worldwide. However, the major constituents of microbial communities that constructed the microbialites have long been disputed. Our new study describes morphological features, growth direction and reproduction characteristic of columnar microfossils obtained from the microbialites, and all characteristics indicate that these microfossils are assignable to a type of photosynthesizing bacteria, known as Pleurocapsales cyanobacteria. Both biomineralization and dolomitization of these Pleurocapsales are evaluated based on in‐situ observations and geochemical analyses. The new results show that the cluster‐branching morphologies, together with common occurrence and strong calcification capacity indicate that Pleurocapsales were key constructors of the microbialites. High Mg/(Mg + Ca) ratios coinciding with the microbialites and Mg‐enrichment in the microfossils suggest that the Pleurocapsales may have catalyzed dolomitization of the microbialites after the end‐Permian mass extinction. Key Points: Four phases of a microbe life cycle are recognized from fossils within microbialites reflecting Pleurocapsales asexual reproductionCommon occurrence and baffling framework indicate that Pleurocapsales cyanobacteria are important in constructing microbialitesPleurocapsales cyanobacteria were an important component of microbialite calcification and magnesium enrichment [ABSTRACT FROM AUTHOR]

The extinction of non‐avian dinosaurs and its cause(s) have been a matter of debate for several decades. Here we measured Hg and its isotopic composition, heavy metals, and magnetic parameter in a terrestrial basin in southeastern China. Hg exhibited anomalies from 66.4 to 65.6 Ma, with near‐zero to positive Δ199Hg values, which reflected the eruption of Deccan Traps (DT) magma. In addition, Hg anomalies coincided with the gradual extinction of non‐avian dinosaurs, thereby consistent with the hypothesis that DT played a key role in the mass extinction. Analysis of paleoclimatic records showed that both the Late Maastrichtian warming event (LMWE) and Dan‐C2 event occurred at the maxima of the 405‐kyr long eccentricity cycle, and the onset of the dinosaur decline was earlier than the LMWE, suggesting that the LMWE played an ancillary role in the mass extinction. The mechanism of how DT caused the mass extinction requires further investigation. Plain Language Summary: The debate concerning the relative importance of the Chicxulub bolide impact and/or Deccan Traps (DT) volcanism as the cause of the extinction of non‐avian dinosaurs at the end of the Cretaceous has lasted for several decades. There is lack of direct geological evidence linking the DT eruption with the non‐avian dinosaur fossil record, so the Chicxulub bolide impact is regarded by many as the dominant—if not the sole—cause of the mass extinction. Therefore, it is necessary to find new geological evidence to clarify this issue. In this study, the concentration of Hg and its isotope systematics were carefully investigated, combined with palaeontology data and palaeoclimate records, we suggest that DT played a key role in the extinction of non‐avian dinosaurs. Key Points: Hg combined with its isotopic composition indicate the record of Deccan Traps (DT) volcanismDT volcanism played an important role in the extinction of non‐avian dinosaursThe inherent mechanism of how DT caused the mass extinction requires further investigation [ABSTRACT FROM AUTHOR]

Great difficulty in characterizing the spatial pattern and scale of regional surface urban heat islands (RSUHIs) over urban agglomerations is mainly attributed to the RSUHI extent exceeding urban boundaries and strong variations in the background climate state and land cover. A new method that successfully addresses these problems by applying the spatial similarity of the land surface temperature (LST) annual cycle in urban agglomerations is proposed to characterize the RSUHI spatial pattern and scale in the Yangtze River Delta of China. This method has good adaptability to complex terrain and climate variations and simultaneously identifies the RSUHI spatial pattern and scale. The RSUHI spatial extent averaged 3.7 × 104 km2 in 2003–2020, which is 1.5–2.0 times the urban extent, and had a fluctuating but increasing tendency. Rapid urbanization and the spatial pattern‐shifting LST anomalies were mainly responsible for the fluctuating RSUHI extent during 2003–2020. Plain Language Summary: In contrast with a single city, urban agglomerations can create regional urban heat islands and threaten environmental sustainability, biodiversity, and resource and energy consumption on a regional scale. Accurately quantifying the spatiotemporal variations of regional urban heat islands is of practical importance to urban planning and environmental management in terms of shaping rational urban clusters, mitigating heat‐related health risks and improving human comfort in urban agglomerations. We propose a new method that reasonably identifies the urban–rural cliff of the land surface temperature in urban agglomerations using a spatial similarity algorithm, and we simultaneously identify the spatial pattern and scale of regional urban heat islands in the Yangtze River Delta of China. The proposed method has great potential in mitigating heat‐related health risks and improving urban design owing to its good adaptability to complex terrain, land cover and climate variations. Key Points: Rapid urbanization leads to strong differences in the annual cycle of the land surface temperature (LST) between urban and nonurban areasA new method based on the similarity of annual cycles of the LST is proposed to quantify regional heat island effectsThis method adapts well to complex terrain, land‐cover changes and climate variations and has great potential in urban planning [ABSTRACT FROM AUTHOR]

Thundersnow is a special kind of thunderstorm that combines snowfall and lightning. A 10‐year thundersnow climatology over China was obtained based on observations during 2008–2017. Our results show that thundersnows are widely distributed in China, and most of the high‐frequency areas are located in the Tibetan Plateau and northeastern China. The average frequency of thundersnow decreases with decreasing altitude, and thundersnow usually occurs at low‐altitude stations once every 10 years. Thundersnow, which likely induces great total snowfall depths, appears mostly in spring, autumn and late winter and can occur in high‐altitude areas in summer. The blizzard probability on a thundersnow day is 12.7%. The percentage of positive cloud‐to‐ground lightning of winter thundersnow is approximately 20.7%, which is lower than those in other seasons. The negative phase of the Arctic Oscillation and anomalous western North Pacific anticyclone are favorable background conditions for thundersnow events. Plain Language Summary: Though the snowfall process is different from common rainfall processes that are accompanied by lightning, it can also occasionally produce lightning. This special type of thunderstorm is called thundersnow. It can induce heavy snowfall, which results in partial paralysis of modern cities. Electrified winter clouds may pose an aviation hazard. Although the frequency of thundersnow is low, it is widely distributed in China. Thundersnow can occur throughout the year, mainly in February‐May and October‐November. Thundersnow events increase the probability of blizzards, especially in the Shandong Peninsula in spring, North China and the Changbai Mountain in autumn, and the middle and lower reaches of the Yangtze River basin and Bohai Rim in winter. The variations of the thundersnow number are closely associated with extratropical atmospheric circulation anomalies. The climatological and atmospheric conditions of thundersnow in China that are revealed by this study help establish an important basis for thundersnow forecasting. Key Points: A 10‐year climatology of thundersnow in China was revealed for the first timeThe high‐frequency areas of thundersnow are mainly located in the Tibetan Plateau and northeastern ChinaThundersnow is significantly influenced by the Arctic Oscillation and associated with the anomalous western North Pacific anticyclone [ABSTRACT FROM AUTHOR]

Precipitation change is determined by changes in frequency and intensity. Based on hourly and daily precipitation data sets in China (1961–2014) and CMIP6 model, this study found that observed inconsistency in the frequency trend at the two time resolutions (hourly and daily) reflected precipitation becoming more concentrated at 13.4% of stations, resulting in the specific precipitation phenomenon of "more hours in one day, but fewer days." However, models exhibited opposite precipitation phenomenon at 16.5% of stations and cannot reproduce the widespread increase in the proportion of extreme precipitation amounts (PA) in the total PA, especially at an hourly resolution. Although stations with significant trend from CMIP6 approximately twice the observation, both CMIP6 and observations showed that frequency and intensity changes dominated the total PA trend at hourly and daily time resolutions, respectively. These results demonstrated that daily precipitation observations could not fully capture the important features of short‐duration rainfall. Plain Language Summary: Do the hourly precipitation frequency and intensity have trends consistent with those of daily precipitation? Based on hourly and daily rain gauge data sets in China (1961–2014) during May–September (warm season), we found that the daily precipitation frequency widely decreased over past decades, but the hourly precipitation frequency did not decrease significantly in most regions. Such a difference led to the phenomenon of "more hours in 1 day, but fewer days" of warm season precipitation. The contribution calculation further revealed that precipitation observed at a coarse time resolution (e.g., daily time scale) could not sufficiently capture the important features of short‐duration rainfall. Compared with the observations, however, the CMIP6 models simulated a significant decreasing trend in hourly precipitation frequency at many sites and thus exhibited the opposite precipitation phenomenon. Moreover, models cannot reproduce the widespread increase in the proportion of extreme precipitation amount (PA) in total PA, especially at an hourly resolution. However, the models exhibited good consistency with the observations in terms of the dominant factors of the PA trend or long‐term change, although the percentages of stations were obviously biased by the models, especially for the trend contribution. Key Points: Observed inconsistent frequency trend between daily and hourly precipitation causes "more hours in 1 day, but fewer days" rainfall featureModels show opposite rainfall feature and miss broad increase of extreme precipitation amount (PA) rate in total PA, especially hourly scaleBoth CMIP6 and observations show frequency and intensity changes dominated the total PA trend at hourly and daily time scales, respectively [ABSTRACT FROM AUTHOR]

The South Asian high (SAH) experienced a decadal weakening in the late 1970s under global warming. Based on an evaluation of the historical runs from CMIP6 models, we quantitatively assessed the contributions of different external forcing using "good" models that reasonably simulated the decadal decline of the SAH. All‐forcing runs yielded the weakened SAH after the late 1970s, albeit the decadal decline was underestimated by most models. Compared to the insignificant contributions of greenhouse gas and natural forcing, anthropogenic aerosol played a dominant role in the decadal decline of the SAH. The increased aerosol likely drove a cooling surface over the Tibetan Plateau (TP) and East China via its effect on radiation. Consequently, the weakened heat source over the TP and associated thermodynamic effects over East China would have driven a cooling of eddy temperature and cyclonic anomalies in the upper troposphere, respectively, thereby causing the decline of the SAH. Plain Language Summary: Under global warming, the South Asian high (SAH) measured by eddy geopotential height experienced a decadal decline in the late 1970s. However, the mechanism responsible for the decadal decline of the SAH has not been investigated. In this study, the contributions of external forcing to the decadal decline of the SAH are accessed using "good" CMIP6 models that can reasonably simulate the decadal changes of SAH. Results indicate that anthropogenic aerosol plays an important role in weakening the SAH. The increased aerosol emission over the Tibetan Plateau (TP) and East China cools the ground through the radiation effect. The weakened heat effect of TP and East China can contribute to the weakening of SAH. By contrast, the contributions of greenhouse gas and natural forcing are almost completely insignificant due to their homogenized and only very slight effects on the upper‐tropospheric eddy temperature over the SAH region, respectively. Key Points: ALL forcing can yield a weakening of the South Asian high (SAH), and anthropogenic aerosol provided the dominant contributionAnthropogenic aerosol drove the decline of the SAH by weakening the effect of the heat source over the Tibetan PlateauThe contribution of greenhouse gas and natural external forcing to the decadal decline of the SAH is insignificant [ABSTRACT FROM AUTHOR]

The continental collision and subduction between the North China Craton and Yangtze Plate resulted in complex multistage tectonic episodes of the Tanlu fault zone. To adequately understand the geodynamic processes of the continental collision, we construct a high‐resolution shear‐wave velocity model of the crust and uppermost mantle using full‐wave ambient noise tomographic method based on a new broadband dense seismic array across the Tanlu fault zone. Our tomographic model reveals the uniquely alternating high‐velocity and low‐velocity anomalies from the lower crust to uppermost mantle across the Tanlu fault zone, which may result from the vertical slab tear of the subducted Yangtze Plate and the subsequent upwelling of hot asthenospheric materials. A prominent mid‐crustal detachment zone is observed along the Tanlu fault zone, which provides direct seismic evidence for the Tanlu fault zone that occurred strongly left‐lateral shearing deformation and may influence the uneven distribution of the strong earthquakes. Plain Language Summary: The Tanlu fault zone is a large‐scale continental tectonic belt in eastern China, which is comparable to the San Andreas fault in the western United States and plays a significant role in controlling the regional tectonics and seismicity. It provides an excellent setting to focus on the understanding of the multistage lithospheric evolution. However, previous collisional dynamic models proposed mainly by geological and geochemical characteristics remain enigmatic, due to the lack of supporting seismic evidence from the deep crustal and upper mantle structure. In this study, we construct a high‐resolution 3D crustal and uppermost mantle structure of the Tanlu fault zone using an advanced seismological imaging method with a new deployed broadband dense seismic array. Our tomographic model reveals the laterally alternating high‐velocity and low‐velocity anomalies across the Tanlu fault zone and a prominent mid‐crustal detachment zone along the Tanlu fault zone. We suggest the variations of the crustal structure may result from the vertical slab tear of the subducted Yangtze Plate and the variations of the mid‐crustal detachment zone play a crucial role in controlling the occurrence of strong earthquakes. Key Points: A high‐resolution seismic structure is probed by a new broadband dense seismic arrayVelocity contrast across the Tanlu fault zone may result from slab tear of the Yangtze Plate and the subsequent upwellingMid‐crustal detachment zone along the Tanlu fault zone may influence the uneven distribution of strong earthquakes [ABSTRACT FROM AUTHOR]