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This study examines marine boundary layer cloud regime transition during a cold air outbreak (CAO) over the Norwegian Sea, simulated by a global storm‐resolving model (GSRM) known as the Simple Cloud‐Resolving Energy Exascale Earth System Model Atmosphere Model (SCREAM). By selecting observational references based on a combination of large‐scale conditions rather than strict time‐matched comparisons, this study finds that SCREAM qualitatively captures the CAO cloud transition, including boundary layer growth, cloud mesoscale structure, and phase partitioning. SCREAM also accurately locates the greatest ice and liquid in the mesoscale updrafts, however, underestimates supercooled liquid water in cumulus clouds. The model evaluation approach adopted by this study takes advantages of the existing computational‐expensive global simulations of GSRM and the available observations to understand model performance and can be applied to assessments of other cloud regimes in different regions. Such practice provides valuable guidance on the future effort to correct and improve biased model behaviors. Plain Language Summary: Cold air outbreaks occur when cold, dry air moves over warmer ocean regions, forming extensive boundary layer clouds. However, current climate models struggle to accurately represent these clouds due to their complex nature. This study examines the performance of the global storm‐resolving model, the Simple Cloud‐Resolving Energy Exascale Earth System Model Atmosphere Model (SCREAM), in simulating marine boundary layer clouds during cold air outbreaks over the Norwegian Sea. This study compares the SCREAM simulated clouds during a cold air outbreak event to observations under similar large‐scale conditions from satellites and ground‐based measurements collected during a field campaign of the Atmospheric Radiation Measurement program. The results indicate that SCREAM successfully simulates three distinct cloud patterns during cold air outbreaks with credible mesoscale structures. Yet, it tends to underestimate supercooled liquid water and consequently, the cloud liquid water fraction, especially in cumulus clouds. The study suggests that using high‐resolution observations under similar large‐scale conditions can effectively evaluate global storm‐resolving models. This approach helps identify areas for improvement without requiring expensive global storm‐resolving model simulation designed for specific cases. Key Points: The Simple Cloud‐Resolving Energy Exascale Earth System Model Atmosphere Model (SCREAMv0), at a resolution of 3 km, simulated three distinctive cloud regimes in cold air outbreaks with credible mesoscale structuresSCREAMv0 qualitatively captures the transition of the cloud phase partitioning based on high‐resolution observationsObservations selected based on similar large‐scale conditions can be important references for global storm‐resolving model evaluation [ABSTRACT FROM AUTHOR]

Vertical structure of mesoscale eddies is key to the eddy‐induced heat/material transport that further affects the climate and marine ecosystem. This study explores the vertical structure of mesoscale eddies in the Kuroshio‐Oyashio Extension region (KOE) and its underlying dynamics. By applying the hierarchical ascending classification to the observational and reanalysis data sets, we classify mesoscale eddies with three distinct kinds of vertical structures. Each kind of eddies exhibits clear spatial aggregation along a distinct zonal band. Eddies have core depths of 100–300 m in the northern part of the KOE and core depths of 300–500 m and 0–100 m in the southern. The eddy splitting or merging does not introduce new kind of eddy vertical structure but causes large intra‐kind variability. The different kinds of eddy vertical structures can be partially accounted for by the baroclinic instabilities at the eddy generation sites and local adjustment process. Plain Language Summary: Mesoscale eddies are swirling motions with a radius ranging from several tens to a hundred of kilometers. The mesoscale eddies can cause strong vertical displacement of isopycnals, yet the vertical structure of such displacement has not been well understood. This study examines the vertical structures of mesoscale eddies in the Kuroshio‐Oyashio Extension region based on the observational and reanalysis data sets. Mesoscale eddies with three distinct kinds of vertical structures are identified. Both the eddy generation and local adjustment during eddy propagation play important roles in the vertical structures of eddies. Key Points: Three vertical structures of mesoscale eddies are classified in the Kuroshio‐Oyashio Extension regionMesoscale eddy splitting or merging causes significant variation of vertical eddy structuresDifferent vertical eddy structures can be partially accounted for by baroclinic instabilities and local adjustment process [ABSTRACT FROM AUTHOR]

Cold‐season methane (CH4) emissions may be poorly constrained in wetland models. We examined cold‐season CH4 emissions simulated by 16 models participating in the Global Carbon Project model intercomparison and analyzed temporal and spatial patterns in simulation results using prescribed inundation data for 2000–2020. Estimated annual CH4 emissions from northern (>60°N) wetlands averaged 10.0 ± 5.5 Tg CH4 yr−1. While summer CH4 emissions were well simulated compared to in‐situ flux measurement observations, the models underestimated CH4 during September to May relative to annual total (27 ± 9%, compared to 45% in observations) and substantially in the months with subzero air temperatures (5 ± 5%, compared to 27% in observations). Because of winter warming, nevertheless, the contribution of cold‐season emissions was simulated to increase at 0.4 ± 0.8% decade−1. Different parameterizations of processes, for example, freezing–thawing and snow insulation, caused conspicuous variability among models, implying the necessity of model refinement. Plain Language Summary: Wetlands in the northern high latitudes are a major source of methane (CH4) to the atmosphere, mainly during the warm season. Previously, models have assumed that cold‐season CH4 emissions are low, but recent observations suggest high‐latitude wetlands can be substantial sources even in winter. We compared CH4 emissions simulated by 16 state‐of‐the‐art wetland models, participating in a model intercomparison project with a focus on the cold‐season in northern wetlands. The model simulations indicated that nearly one third of annual emissions were simulated to occur from September to May, and CH4 emissions to the atmosphere were not negligible even under freezing air temperatures, although the results differed greatly among the models. However, field studies suggest cold‐season emissions account for an even larger fraction of annual emissions. These results highlight the contribution of cold‐season emissions to the annual CH4 budget, which future climatic warming is expected to affect severely, and they also show that simulations of cold‐season CH4 emissions from wetlands need to be improved. Key Points: Cold‐season methane (CH4) emissions simulated by 16 Global Carbon Project‐CH4 wetland models were analyzedMost models underestimate the cold‐season emissions in comparison with observational dataFurther model improvement by including cold‐season processes is required to reduce the model bias and uncertainty [ABSTRACT FROM AUTHOR]

Various modeling studies have examined the climatic effects of either the Central American Seaway or the Indonesian seaway. The co‐existence of these two tropical seaways may have a greater influence than the existence of a single seaway. Although the dual seaway situation is closer to that reconstructed during Miocene/Pliocene, relevant studies remain scarce. Here, we investigate the co‐effects of dual tropical seaway changes on the Pacific circulation through a set of sensitivity experiments. Our results show that the combined shallow opening of tropical seaways can generate an active Pacific meridional overturning circulation and maintain strong upwelling conditions along the equatorial Pacific, which may have helped favor a "biogenic bloom" during the late Miocene and early Pliocene. Moreover, the logically successive closure of the tropical seaways can provide patterns of zonal sea surface temperature gradients that are similar to those recorded in the equatorial Pacific from the late Miocene to the Pliocene. Plain Language Summary: During the late Miocene and the Pliocene, changes in the Central American and the Indonesian seaways geometry are very important for ocean circulation and global climate. Various modelling studies have examined the separate effects of these two tropical seaways, especially their link to the onset of the Northern Hemisphere ice sheets through changes in the Atlantic meridional overturning circulation and associated heat and moisture transport. Although the existence of dual tropical seaways is closer to the reality, there are very scarce modelling studies exploring the co‐effects of dual tropical seaway changes, especially on the Pacific ocean circulation. Here we provide the results of modelling study on this issue. Our results show that the combined shallow opening of tropical ways can generate an active Pacific meridional overturning circulation (i.e., absent in modern conditions) by which the meridional and zonal sea surface temperature gradient in the Pacific largely reduce. In contrast, a deeper opening of tropical seaways can not produce these changes in the Pacific ocean circulation. This study provides insights into and a better understanding of the role of tropical seaways in shaping the Pacific climate and highlights the importance of the sill depth of each seaway. Key Points: The co‐effects of opening of two tropical seaways on the Pacific circulation are investigated with climate modelShallow opening of tropical seaways can generate an active Pacific meridional overturning circulation, whilst a deeper condition can notThe stepwise closure of the tropical seaways can provide similar‐to‐record patterns of zonal sea surface temperature gradients [ABSTRACT FROM AUTHOR]

Kinetic‐size magnetic holes (KSMHs) can accelerate and heat the particles, resulting the energy dissipation in space plasmas. KSMHs in the terrestrial foreshock region are statistically investigated based on the Magnetospheric Multiscale data from October 2015 to December 2019. A total of 98 KSMHs are successfully selected, and most of them are accompanied by electron vortices. The fluxes of electrons at ∼90° of pitch angle enhance inside the magnetic holes, where the perpendicular and total electron temperature increase, and the parallel electron temperature slightly decreases inside these magnetic holes. Moreover, we reveal a novel phenomenon that a lot of the observed KSMHs are probably moving toward the Sun in the plasma flow frame. Such sunward propagating KSMHs are detected for the first time in the foreshock region. We propose that these observed KSMHs are probably generated in the foreshock region and then propagate to the Sun. Plain Language Summary: Magnetic hole, characterized by the significant decrease of magnetic strength, is usually observed in the planetary magnetosphere. Kinetic‐size magnetic holes (KSMHs) with the scale below ion gyroradius have attracted much interest in recent years. KSMHs can accelerate and heat the particles, resulting the energy dissipation in space plasmas. Based on the Magnetospheric Multiscale data, KSMHs in the terrestrial foreshock region are statistically investigated for the first time. We reveal some novel phenomenon for the observed KSMHs in the foreshock region. Key Points: We present the observational evidence of kinetic‐size magnetic holes (KSMHs) in the terrestrial foreshock regionA lot of the observed KSMHs are probably moving toward the Sun in the plasma flow frameThese observed KSMHs are probably generated in the foreshock region and then propagate toward the Sun [ABSTRACT FROM AUTHOR]

Utilizing data from the Magnetospheric Multiscale mission, the sub‐structures of the separatrix region during reconnection are investigated. A small current system in the separatrix region is embedded in the large Hall current system, which appears as a quadrupole current. This small current system has an opposite direction to the Hall current and cancels part of the Hall magnetic field. The formation of the quadrupole current is possibly related to the patchy parallel electric field. The electric field in the separatrix region can be divided into three sub‐layers according to the electron frozen‐in condition. En enhances in two outside sub‐layers, where the strong En is supported by the Hall term and electron pressure gradient term, and the nearly zero En, separating the enhanced electric fields, is caused by a small flow and electron density gradient. Our observations imply complex dynamics in the separatrix region during magnetic reconnection. Plain Language Summary: Magnetic reconnection is an explosive energy conversion process that converts magnetic energy to particles. Meanwhile, the topology of the magnetic field is changed. Many phenomena in space are related to magnetic reconnection, like solar flares and aurora. The separatrix is the layer separating the plasmas not yet entered the reconnection process and those already processed by reconnection. The characteristics of plasmas are quite different at the two sides of the separatrix, which makes the separatrix dynamic. With high‐resolution data from the Magnetospheric Multiscale mission, we investigate the sub‐structures of the separatrix region in a reconnection event in the magnetotail. The quadrupole current and multi‐layer electric field are observed in the separatrix region. The quadrupole current is possibly related to the patchy parallel electric field. And the multi‐layers electric field are caused by the complex electron flow patterns. Our observations reveal the highly‐structured nature of the separatrix region and may help to improve our understanding of the reconnection process. Key Points: Quadrupole current and multi‐layer electric field are observed in the separatrix regionQuadrupole current is possibly related to the patchy parallel electric fieldMulti‐layer electric field are caused by complex electron flow patterns [ABSTRACT FROM AUTHOR]

Substorms are a fundamental phenomenon in planetary magnetospheric systems. Using Cassini measurements, we report a typical event in which four successive dipolarization fronts (DFs) were observed within 1 hour during the substorm in Saturn's magnetotail. The last three DFs caused a type of stepwise electron acceleration and generated energetic electrons. The pitch angle distributions of the electrons show evidence of the Fermi acceleration mechanism behind these DFs. Therefore, we infer the magnetotail dynamics process during Saturn's substorm: The stepwise acceleration by successive DFs powerfully accelerates the field‐aligned electrons and generates field‐aligned energetic electrons. These high‐energy electrons are injected into the inner magnetosphere and become an important trigger of Saturn's aurora. Our results show an efficient acceleration mechanism for the electrons caused by successive DFs and confirm an important source of energetic particles during the substorm in Saturn, and these findings improve our understanding of Saturn's substorm and magnetotail dynamics. Plain Language Summary: Substorms play a role in the energization and transport of plasmas in planetary magnetospheres. During substorms, what specific dynamic processes contribute to particle acceleration and transport remains an important question. In our work, using measurements from the Cassini spacecraft, we report a typical event in which four successive dipolarization fronts (DFs) were observed within 1 hour during the substorm in Saturn's magnetotail. The last three successive DFs cause energetic electrons by stepwise electron acceleration. The electron acceleration is possibly caused by the Fermi acceleration mechanism, which mainly enhances the electron velocity component parallel or antiparallel to the local magnetic field. Our study provides an explanation for the energetic particle injection source of Saturn's aurora and improves our understanding of Saturn's substorm and magnetotail dynamics. Key Points: Four successive dipolarization fronts (DFs) are identified in Saturn's magnetotail during one substormThree of the successive DFs cause a type of stepwise electron acceleration, generating energetic electronsAccording to the electron pitch‐angle distribution, the stepwise electron acceleration is identified as the Fermi acceleration mechanism [ABSTRACT FROM AUTHOR]

Based on the unprecedented high‐resolution data from the Magnetospheric Multiscale mission, we investigate the energy dissipation in turbulent reconnection outflow during turbulent magnetic reconnection in the terrestrial magnetotail. It is found that this reconnection outflow has plenty of intermittent structures at kinetic scales accompanied by abundant current filaments. Strong energy dissipation occurs in the intermittent structures with a high partial variance of increments index, and the regions with strong current filaments. Further analyses reveal that electron heating with the presence of increase in electron temperature occurs in the intermittent structures and the regions with strong currents. This electron heating is more significant in the component parallel to the magnetic field. Our observations demonstrate that intermittent dissipation at kinetic scales occurs in the turbulent reconnection outflow. Plain Language Summary: Magnetic reconnection is an essential physical process in space, astrophysical, and laboratory plasmas, and it can effectively convert magnetic energy into particle energy accompanied by the change of magnetic field topology in a short time period. It has already been confirmed that magnetic reconnection can produce turbulent reconnection outflows. How and where the energy dissipation takes place in reconnection outflows remains a remarkable open question until now. Thanks to the unprecedented high time resolution data of the Magnetospheric Multiscale mission, we investigate the energy dissipation in turbulent reconnection outflow in the terrestrial magnetotail. Our observations reveal that intermittent dissipation at kinetic scales with strong currents occurs in the turbulent reconnection outflow. Key Points: Intermittent structures at kinetic scales accompanied with strong current filaments are abundant in turbulent reconnection outflowsStrong energy dissipation and electron heating occur in the intermittent structures and the regions with strong current filamentsThere exists intermittent dissipation at kinetic scales in turbulent reconnection outflows [ABSTRACT FROM AUTHOR]

Dipolarization front (DF), characterized by a sharp increase of the south‐north component of the magnetic field, is suggested to play an important role in transferring plasmas, magnetic fluxes, and energy in the planetary magnetosphere. Using the measurements from the Cassini spacecraft between January 1, 2005 and June 15, 2011, we successfully selected 96 DF events, and obtained the global spatial distribution of DFs in the Saturn's magnetosphere. For the first time, we found that DFs are distributed not only in the nightside magnetotail but also in the dayside magnetosphere. The dayside DF events are mainly located from X = 10 RS to X = 30 RS (RS is the Saturn's radius) while the nightside events have a wide range, up to X∼−50 RS. Moreover, the DFs are observed to be asymmetric in the south‐northern hemisphere: ∼70% of events in the northern hemisphere and ∼30% of events in the southern hemisphere, which is likely to be due to the asymmetric orbit coverage of the Cassini in south‐northern hemisphere. The occurrence of dayside DFs provides a strong evidence that the magnetic reconnection could also occur in the dayside of Saturn's magnetosphere. Thus, our results concerning the location and distribution of DFs are helpful for the study of the site of magnetic reconnection and energy transport/dissipation in Saturn's magnetosphere. Plain Language Summary: Saturn's magnetosphere is influenced by not only the solar wind, but more importantly the internal sources. Therefore, its magnetosphere would show different characteristics from terrestrial planets. Dipolarization front (DF), characterized by a sharp increase of the south‐north component of the magnetic field, is directly and closely related to magnetic reconnection, planetary substorm and planetary aurora, and can be a great medium for studying the magnetosphere's response to the solar wind and internal sources. In this work, using the measurements from the Cassini, we selected 96 DF events and obtained the global spatial distribution of DFs in the Saturn's magnetosphere. For the first time, we found that quite a big portion of DF events appear in the dayside magnetosphere. Therefore, we propose that the dynamics processes that generally occur at the magnetotail can extend to the whole magnetosphere in Saturn. Our work provides further evidence for the previous studies that the magnetic reconnection occurs in Saturn's dayside magnetodisc. Key Points: A complete global distribution is provided to show the location and local time of dipolarization fronts in Saturn's magnetosphereThere is a surprising large portion of dipolarization fronts observed at the dayside of Saturn's magnetosphereOur results support the existence of dayside magnetodisc reconnection in Saturn [ABSTRACT FROM AUTHOR]

We perform a statistical analysis on current density, energy conversion, and electron acceleration in the primary flux ropes (PFRs) and the secondary flux ropes (SFRs) distinguished by out-ofplane electron current, respectively. It is found that current filaments are plentiful in both PFRs and SFRs. The closer to the center of the SFRs, the stronger the |J| is. The J•E' is intermittent in the PFRs. However, J•E' almost stays positive in the SFRs. The local adiabatic acceleration of the electrons in the PFRs and the SFRs are explored. Fermi and betatron acceleration are closely related to the adjacent magnetic field and bulk flow which can lead to the contraction/relaxation of the PFRs and SFRs and enhance/reduce the gradient of the magnetic field. The acceleration by the parallel electric field is significant in the SFRs. Our results can help to improve the understanding of the PFRs and SFRs and their roles in the magnetotail dynamics. Plain Language Summary Flux ropes, characterized by bipolar change of normal component of the magnetic field and enhancement of the core filed, are 3D magnetic structures. It is believed that flux ropes are dynamic and they usually play an important role in magnetic reconnection, such as dissipating energy and accelerating electrons. Flux ropes can be divided into primary flux ropes (PFRs) and secondary flux ropes (SFRs) according to different generation mechanisms. Though flux ropes have been investigated for decades, the statistical properties of the PFRs and the SFRs have not been obtained and compared. The commonalities and differences between PFRs and SFRs are ambiguous. Using the unprecedented high time resolution data of the Magnetospheric Multiscale (MMS) mission, we perform statistical analysis on current density, energy conversion, and electron acceleration in the PFRs and the SFRs, respectively. Our results may help to improve the understanding of the PFRs and SFRs and their roles in magnetotail dynamics. [ABSTRACT FROM AUTHOR]

Using four‐point measurements from the Magnetospheric Multiscale (MMS) mission, we identify whistler waves at the boundary of an ion scale magnetic hole, which should be locally excited rather than propagated from other regions. Based on the measured local plasma parameters, which include those for bidirectional electron beams with electron temperature anisotropy, the frequency range with the growth rate derived from kinetic theory is consistent with the observations, while the growth rate in the absence of such beams is negative; hence, the observed whistler waves are locally excited by the bidirectional electron beams with electron temperature anisotropy. The dispersion relation, derived from one‐dimensional particle‐in‐cell simulations that are conducted using the inputs of the bidirectional electron beams with electron temperature anisotropy, agrees well with the one from kinetic theory, which further supports this excitation mechanism. Our results shed light on a new excitation mechanism for whistler waves. Plain Language Summary: Whistler waves are nearly field‐aligned propagating and right‐hand polarized electromagnetic modes with the frequency between lower hybrid frequency and electron cyclotron frequency. Whistler waves are frequently and widely detected in the planetary magnetosphere and the interplanetary space and play an important role in the particle dynamics therein. For example, the electrons could be effectively accelerated by the electromagnetic whistler waves. Thanks to the unprecedented high time resolution and multipoint data from the Magnetospheric Multiscale (MMS) mission, the whistler waves are identified at the boundary of a magnetic hole in the magnetosheath. Based on the measured local plasma parameters including bidirectional electron beams with electron temperature anisotropy, both the linear theory based on kinetic plasma and one‐dimensional particle‐in‐cell (PIC) simulations confirm that the observed whistler waves are locally excited by the presence of bidirectional field‐aligned electron beams with electron temperature anisotropy for the first time. Our results shed new light on new excitation mechanism for whistler waves. Key Points: Whistler waves are identified at the boundary of a magnetic holeLinear theory and simulations confirm that whistler waves are excited by bidirectional electron beams with temperature anisotropyOur results shed new light on new excitation mechanism for whistler waves [ABSTRACT FROM AUTHOR]

Dipolarization front (DF), embedded in fast plasma flow, is a sharp structure with the increase of Bz in a short time and plays an important role in the energy dissipation and particle accelerations in the magnetotail. However, detailed physics at the small scales is still unclear in the DF due to the limitation of the previous mission. In the present study, an electron‐scale plateau in Bz is observed at the DF by Magnetospheric Multiscale (MMS) mission. By analyzing the velocity of the electrons, we find that the electron‐scale plateau is surrounded by a sub‐ion‐scale electron vortex, which is the first observation of electron vortex at the DF as far as we know. The magnetic field generated by the electron vortex cancels parts of the increase of Bz and causes the plateau. Strong asymmetric electric field and demagnetization of electrons and ions are observed at the boundary of the electron vortex. These results shed new light on that small‐scale structures can develop within the ion‐scale DF and affect the evolution and kinetic effects at the DF. Key Points: A sub‐ion‐scale electron vortex is observed at a dipolarization frontThe excited magnetic field of the electron vortex suppresses parts of the increase of Bz and causes the plateau at the dipolarization frontStrong asymmetric electric field and demagnetization of electrons and ions are observed at the boundary of the electron vortex [ABSTRACT FROM AUTHOR]

Using high‐resolution data of Magnetospheric Multiscale mission, we observed a gradual but periodical dipolarization process (DPs) in the Earth's magnetotail for the first time. These sub‐DPs, characterized by increase of Bz component and magnetic magnitude Bt, have a period of ~16 s. The electrons have a cigar distribution in the first three sub‐DPs but have a pancake distribution in the last sub‐DP, which excites two oppositely propagating whistler waves. At the trailing boundary of the last sub‐DP, Bz decreases sharply. Meanwhile, strong tailward and duskward plasma flow, intense current, ion and electron demagnetization, and positive energy conversion from the fields to the plasmas are observed at this boundary. By comparing the motion of this boundary with the plasma flow, we infer that the flow rebounds in longer period of the last DP and causes perpendicular electron acceleration. The periodical sub‐DPs and kinetic effects on the DP could improve our understanding of substorm and the magnetotail dynamics. Key Points: A gradual but periodical dipolarization process (DP) is observed in the magnetotail for the first timeDifferent electron distributions are observed in the different sub‐DPsDynamic process and fine structures in the last sub‐DP are analyzed [ABSTRACT FROM AUTHOR]

Seasonal water storage fluctuations are critical for evaluating water scarcity linked to climate forcing and human intervention. Here we compare seasonal changes in land total water storage anomalies using seven global hydrologic and land surface models (WGHM, PCR‐GLOBWB, and five GLDAS models) to GRACE satellite data in 183 river basins globally. This work builds on previous analysis that focused on total water storage anomaly trends. Results show that most models underestimate seasonal water storage amplitudes in tropical and (semi)arid basins and land surface models generally overestimate amplitudes in northern basins. Some models (CLM‐5.0 and PCR‐GLOBWB) agree better with GRACE than others. Causes of model‐GRACE discrepancies are attributed to missing storage compartments (e.g., surface water and/or groundwater) and underestimation of modeled storage capacities in tropical basins and to variations in modeled fluxes in northern basins. This study underscores the importance of considering water storage, in addition to water fluxes, to improve global models. Plain Language Summary: We are relying more and more on global models to understand the water cycle, but we need to assess the reliability of model output. In this study we compare seasonal amplitudes in land total water storage from global models with those from GRACE satellite data in river basins globally. We found that seasonal amplitudes in total water storage account for more than half of the total signal, except in semiarid basins. Seasonal amplitudes are highest in tropical basins and lowest in semiarid basins. Some models agree better with GRACE than others (CLM‐5.0 and PCR‐GLOBWB). Most models underestimate GRACE‐derived seasonal amplitudes in tropical and semiarid basins but overestimate seasonal amplitudes in northern high latitude basins. The main cause of the discrepancies in tropical basins is likely insufficient storage capacity and lack of surface water inundation to accommodate the large seasonal storage variations. In northern high latitude basins, differences in snow physics and evapotranspiration increase seasonal amplitudes in water storage in newer versions of land surface models, overestimating GRACE‐derived seasonal amplitudes and reducing agreement with GRACE relative to earlier versions. Reliable models of seasonal variations in water storage are critical for assessing water scarcity, estimating response to climate extremes, and managing water resources. Key Points: Modeled seasonal amplitudes are underestimated in tropical and semiarid basins and overestimated in northern basins relative to GRACEModel‐GRACE discrepancies are attributed to insufficient storage capacities in tropical basins and biases in fluxes in northern basinsThis study highlights the value of using water storage, in addition to traditional water flux, in assessing and improving global models [ABSTRACT FROM AUTHOR]

Abstract: The North China Plain (NCP) is a region with high level of seismic hazard. Previous Global Positioning System measurements, however, have shown a near absence of present‐day crustal deformation. Using updated Global Positioning System data covering three blocks of the eastern China, we discover that interseismic deformation in the NCP takes place in an ~1,100 km wide left‐lateral shear zone of roughly east‐west orientation. The 6.0 ± 1.3 mm/yr interseismic left‐lateral shear over the NCP results in contemporary deformation that is eventually accommodated by earthquake ruptures of right‐lateral strike‐slip along the north‐northeast trending faults and anticlockwise block rotates. We suggest that rapid eastward motion of the rigid South China block, with respect to the rigid Amurian block, has created a left‐lateral shear couple to twist the nonrigid NCP to form the contemporary deformation. [ABSTRACT FROM AUTHOR]