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The Tibetan Plateau (TP) region, also known as the “Asian water tower”, provides a vital water resource for downstream regions. Previous studies of water cycle changes over the TP have been conducted with climate models of coarse resolution in which deep convection must be parameterized. In this study, we present results from a first set of high-resolution climate change simulations that permit convection at approximately 3.3-km grid spacing, with a focus on the TP, using the Icosahedral Nonhydrostatic Weather and Climate Model (ICON). Two 12-year simulations were performed, consisting of a retrospective simulation (2008–20) with initial and boundary conditions from ERA5 reanalysis and a pseudo-global warming projection driven by modified reanalysis-derived initial and boundary conditions by adding the monthly CMIP6 ensemble-mean climate change under the SSP5-8.5 scenario. The retrospective simulation shows overall good performance in capturing the seasonal precipitation and surface air temperature. Over the central and eastern TP, the average biases in precipitation (temperature) are less than −0.34 mm d−1(−1.1°C) throughout the year. The simulated biases over the TP are height-dependent. Cold (wet) biases are found in summer (winter) above 5500 m. The future climate simulation suggests that the TP will be wetter and warmer under the SSP5-8.5 scenario. The general features of projected changes in ICON are comparable to the CMIP6 ensemble projection, but the added value from kilometer-scale modeling is evident in both precipitation and temperature projections over complex topographic regions. These ICON-downscaled climate change simulations provide a high-resolution dataset to the community for the study of regional climate changes and impacts over the TP.

Introduction: Frequency of imaging markers (FIM) has been described as a novel predictor for hematoma expansion after intracerebral hemorrhage (ICH). A revised definition of hematoma expansion that incorporates intraventricular hemorrhage (IVH) growth, that is, revised hematoma expansion (RHE), has also been proposed. Nevertheless, the associations between FIM and IVH growth or RHE remains unexplored. The objective of this study was to assess the influence and performance of the FIM on two types.Materials and Methods: Patient selection and variables were based on our published protocol. FIM was defined as the ratio of the number of imaging markers to the onset-to-neuroimaging time. The association between FIM and two definitions was tested by multivariate analysis. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the FIM on two definitions were also evaluated.Results: There were 303 (20.36%) and 583 (39.18%) subjects in the IVH growth and RHE, respectively. Multivariate analysis demonstrated that FIM was associated with both IVH growth and RHE (odds ratio [OR] = 1.96, 95% confidence interval [CI] = 1.60–2.39; OR = 15.01, 95% CI = 10.51–21.43, respectively). The optimal cutoff points for FIM to predict IVH growth and RHE were 0.63 and 0.62, with AUC, sensitivity, specificity, PPV, and NPV of 0.66, 0.50, 0.78, 0.36, and 0.86 versus 0.80, 0.60, 0.93, 0.84, and 0.78, respectively.Discussion and Conclusion: FIM was not only a predictor of IVH growth, but also of RHE. These findings may have important clinical implications for decision-making based on risk stratification of patients with ICH.

Accurately assessing and tracking the progression of liver-specific injury remains a major challenge in the field of biomarker research. Here, we took a retrospective validation approach built on the mutuality between serum and tissue biomarkers to characterize the liver-specific damage of bile duct cells caused by α-naphthyl isothiocyanate (ANIT). We found that carboxylesterase 1 (CES1), as an intrahepatic marker, and dipeptidyl peptidase 4 (DPP-IV), as an extrahepatic marker, can reflect the different pathophysiologies of liver injury. Levels of CES1 and DPP-IV can be used to identify liver damage itself and the inflammatory state, respectively. While the levels of the conventional serological biomarkers alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were all concomitantly elevated in serum and tissues after ANIT-induced injury, the levels of bile acids decreased in bile, increased in serum, and ascended in intrahepatic tissue. Although the level of γ-glutamyl transpeptidase (γ-GT) changed in an opposite direction, the duration was much shorter than that of CES1 and was quickly restored to normal levels. Therefore, among the abovementioned biomarkers, only CES1 made it possible to specifically determine whether the liver cells were destroyed or damaged without interference from inflammation. CES1 also enabled accurate assessment of the anti-cholestasis effects of ursodeoxycholic acid (UDCA; single component) and Qing Fei Pai Du Decoction (QFPDD; multi-component). We found that both QFPDD and UDCA attenuated ANIT-induced liver damage. UDCA was more potent in promoting bile excretion but showed relatively weaker anti-injury and anti-inflammatory effects than QFPDD, whereas QFPDD was more effective in blocking liver inflammation and repairing liver damage. Our data highlights the potential of the combined use of CES1 (as an intrahepatic marker of liver damage) and DPP-IV (as an extrahepatic marker of inflammation) for the accurate evaluation and tracking of liver-specific injury—an application that allows for the differentiation of liver damage and inflammatory liver injury.

Precipitation projections over the Tibetan Plateau (TP) show diversity among existing studies, partly due to model uncertainty. How to develop a reliable projection remains inconclusive. Here, based on the IPCC AR6–assessed likely range of equilibrium climate sensitivity (ECS) and the climatological precipitation performance, the authors constrain the CMIP6 (phase 6 of the Coupled Model Intercomparison Project) model projection of summer precipitation and water availability over the TP. The best estimates of precipitation changes are 0.24, 0.25, and 0.45 mm d−1(5.9 %, 6.1 %, and 11.2 %) under the Shared Socioeconomic Pathway (SSP) scenarios of SSP1–2.6, SSP2–4.5, and SSP5–8.5 from 2050–2099 relative to 1965–2014, respectively. The corresponding constrained projections of water availability measured by precipitation minus evaporation (P–E) are 0.10, 0.09, and 0.22 mm d−1(5.7 %, 4.9 %, and 13.2 %), respectively. The increase of precipitation and P–E projected by the high-ECS models, whose ECS values are higher than the upper limit of the likely range, are about 1.7 times larger than those estimated by constrained projections. Spatially, there is a larger increase in precipitation and P–E over the eastern TP, while the western part shows a relatively weak difference in precipitation and a drier trend in P–E. The wetter TP projected by the high-ECS models resulted from both an approximately 1.2–1.4 times stronger hydrological sensitivity and additional warming of 0.6 °C–1.2 °C under all three scenarios during 2050–2099. This study emphasizes that selecting climate models with climate sensitivity within the likely range is crucial to reducing the uncertainty in the projection of TP precipitation and water availability changes.

The Tibetan Plateau (TP) provides vital water resources for downstream regions, with spring precipitation contributing considerably to the annual totals over the southeastern TP. The added value of convection‐permitting modeling in simulating the spring climate over the TP is uncertain. Here, we conducted and compared decade‐long regional convection‐permitting (3.3 km) and convection‐parameterized (13.2 km) Icosahedral Nonhydrostatic Weather and Climate Model (ICON) simulations to reproduce the atmospheric water cycle in spring over the TP. Results indicated that 3.3 km mesh ICON (ICON_3.3 km) exhibited notable added value in simulating the spring atmospheric water cycle over the TP. ICON_3.3 km reduced the wet biases of precipitation in the ERA5 reanalysis and 13.2 km mesh ICON (ICON_13.2 km) simulations, and improved the simulation of surface evaporation over the central and eastern TP. The reduction in the simulated precipitation in ICON_3.3 km was primarily followed by a decrease in surface evaporation from March to May, second by a reduction in water vapor flux convergence in May due to decreased water vapor inflow from the southeastern TP. Furthermore, compared to ICON_13.2 km, ICON_3.3 km alleviated the “drizzling” bias, leading to drier surface soils and decreased evaporation, and lead to 3% decrease in the fraction of evaporation converted into precipitation. Sensitivity experiments conducted at resolution of 13.2 km but turning off the convection parameterization demonstrated that both explicit representation of convection and enhanced horizontal resolution were crucial for accurately representing the spring atmospheric water cycle over the TP. Our results highlighted the need to develop kilometer‐scale models for successfully reproducing the climate characteristics across the TP. Climate modeling is evolving toward kilometer‐scale or convective‐permitting model (CPM). The added value of regional CPM in simulating the spring climate over the Tibetan Plateau (TP), known as “Asian Water Tower,” is unknown. Here, we have performed and compared two decade‐long regional climate simulations at two horizontal resolutions: convection permitting (3.3 km) and convection parameterized (13.2 km), to reproduce the atmospheric water cycle in spring over the TP. Results indicated that the CPM reduced the wet biases in the latest reanalysis data and the convection‐parameterized model over the central and eastern TP. The reduction of wet biases was mainly followed by the decreased surface evaporation, which was associated with the alleviation of “drizzling” bias in CPM. We further showed evidences that both explicit representation of convection and enhanced horizontal resolution were crucial for accurately representing the spring climate over the TP. Our findings highlight the importance of developing high‐efficiency kilometer‐scale (<4 km) models for reproducing all the climate characteristics across the TP region. Regional convection permitting model exhibited evident added value in simulating the spring atmospheric water cycle over the Tibetan Plateau (TP)Reduced precipitation by convective‐permitting model was mainly followed by decrease in surface evaporation, associated with the alleviation of drizzling biasesBoth explicit convection and enhanced resolution were crucial for well representing the spring atmospheric water cycle over the TP Regional convection permitting model exhibited evident added value in simulating the spring atmospheric water cycle over the Tibetan Plateau (TP) Reduced precipitation by convective‐permitting model was mainly followed by decrease in surface evaporation, associated with the alleviation of drizzling biases Both explicit convection and enhanced resolution were crucial for well representing the spring atmospheric water cycle over the TP

The quantitative relationship between Mesoscale Convective Systems (MCSs) and floods over East Asia has not been established. In this study, MCSs are clustered into four types with Self‐Organizing Map approach. Floods in June‐August of 2000–2021 are linked with different types of MCS by automated algorithms we constructed. We find that among the major floods (potential flood peak periods), 91% (87%) are related to MCS, 65% (78%) are dominated by MCS, and 38% (20%) are dominated by multi‐types of MCS. Types 1 and 2 MCS have higher flood‐inducing efficiencies than common MCS (Type‐4). Type‐1 MCS, characterized by the least number (2% of the total number), the largest precipitation volume, longest lifetime, slowest moving, strongest precipitation, can most efficiently produce floods. Type‐2 MCS, characterized by the second largest precipitation volume, more numerous than Type‐1 particularly over land, can induce floods not only relatively efficiently but also more frequently than Type‐1. Mesoscale Convective Systems (MCS) can cause large flood events but how they work in East Asia at climatic scale remains unexplored. In this study, we tracked MCS over the time period of 2000–2021 and grouped them into four types using the Self‐Organizing Map approach. We connected summer floods with the four types of MCS using automated algorithms. We found that most large flood events and potential flood peak periods are dominated by MCS. Type‐1 MCS, which features large land‐rain area, longest lifetime, slowest movement and strongest precipitation, is most efficient in inducing floods. A Longer lifetime not only contributes to greater total precipitation volume but also increases the overlap area, thereby enhancing the precipitation volume per area. The slow movement further increases the overlap area. The high overlap area helps reduce the proportion of precipitation absorbed by the soil. Type‐2 MCS, which features with the second largest precipitation volume, occurs more frequently than Type‐1 especially over land, and can cause floods more frequently than Type‐1. These findings can enhance our understanding of flood formation over East Asia. Among the major floods (potential flood peak periods) occurred in 2000–2021 summer, 91% (87%) are related to Mesoscale Convective Systems (MCS), and 66% (78%) are dominated by MCSType‐1 MCS is the most efficient among the four types in causing floods for its strongest precipitation rate, longest lifetime and slowest movementLong lifetime and slow movement increase the overlap area, boosting precipitation per area and reducing the proportion of rainfall absorbed by soil Among the major floods (potential flood peak periods) occurred in 2000–2021 summer, 91% (87%) are related to Mesoscale Convective Systems (MCS), and 66% (78%) are dominated by MCS Type‐1 MCS is the most efficient among the four types in causing floods for its strongest precipitation rate, longest lifetime and slowest movement Long lifetime and slow movement increase the overlap area, boosting precipitation per area and reducing the proportion of rainfall absorbed by soil

Identifying the alert groups of mechanism-based inactivators of human cytochrome P450s (hCYPs) is very helpful for early prediction of drug toxicity and for rational drug design to avoid idiosyncratic toxicity. Here, we report that a natural compound bufalin (BF) could time-dependently inactivate hCYP3A via complex CYP-catalyzed cascade oxidative metabolism. Metabolite profiling and time-dependent inhibition assays showed that 3-keto-bufalin (3-KBF), a unique nonpolar oxidative metabolite of BF, was the key substance responsible for hCYP3A inactivation. Further investigations demonstrated that 3-KBF was further metabolized by hCYPs to generate two mono-hydroxylated metabolites, which could be readily dehydrated and then covalently bound on glutathione or hCYP3A4. Collectively, this study uncovers unique CYP-catalyzed cascade oxidative pathways of BF in which two reactive intermediates bearing a Michael acceptor are finally formed as hCYP3A inactivators. These findings expand the current knowledge of CYP inactivators and suggest that some steroids bearing the 3-keto group may trigger time-dependent CYP3A inactivation.

ABSTRACTA new regional coupled ocean–atmosphere model, WRF4-LICOM, was used to investigate the impacts of regional air–sea coupling on the simulation of the western North Pacific summer monsoon (WNPSM), with a focus on the normal WNPSM year 2005. Compared to WRF4, WRF4-LICOM improved the simulation of the summer mean monsoon rainfall, circulations, sea surface net heat fluxes, and propagations of the daily rainband over the WNP. The major differences between the models were found over the northern South China Sea and east of the Philippines. The warmer SST reduced the gross moist stability of the atmosphere and increased the upward latent heat flux, and then drove local ascending anomalies, which led to the increase of rainfall in WRF4-LICOM. The resultant enhanced atmospheric heating drove a low-level anomalous cyclone to its northwest, which reduced the simulated circulation biases in the stand-alone WRF4 model. The local observed daily SST over the WNP was a response to the overlying summer monsoon. In the WRF4 model, the modeled atmosphere exhibited passive response to the underlying daily SST anomalies. With the inclusion of regional air–sea coupling, the simulated daily SST–rainfall relationship was significantly improved. WRF4-LICOM is recommended for future dynamical downscaling of simulations and projections over this region.

Today, tumor therapy and its therapeutic efficiency evaluation are conducted separately, and current imaging techniques cannot evaluate tumor-therapeutic effects in real time. Therefore, it is of great importance to develop highly efficient theranostic strategies which are able to evaluate their tumor-therapeutic effects in real time. In this work, by rational design of a small molecular near-infrared probe Cys(StBu)-Asp-Glu-Val-Asp-Lys(Cypate)-CBT (Cy-CBT) and using a CBT-Cys click condensation reaction, we facilely prepare an intelligent nanoparticle Cy-CBT-NPwhich is able to evaluate its photothermal therapy (PTT) efficiency on tumors by fluorescence “Turn-On”. Fluorescence of Cy-CBT-NPis quenched and photothermal responsive. Upon caspase 3 (Casp3) cleavage of its DEVD substrates, Cy-CBT-NPdisassembles to turn the fluorescence “On”, which in turn evaluates the PTT efficiency of the nanoparticle on cells and tumors in real time. We envision that our smart strategy could be applied for PTT and real-time evaluation of the therapeutic efficiency of solid tumors in the near future.

Regional coupled modeling is one of the frontiers of regional climate modeling, but intercomparison has not been well coordinated. In this study, a community regional climate model, WRF4, with a resolution of 15 km, was coupled with a high-resolution (0.1°) North Pacific Ocean model (LICOM_np). The performance of the regional coupled model, WRF4_LICOM, was compared to that of another regional coupled model, RegCM4_LICOM, which was a coupling of version 4 of the Regional Climate Model (RegCM4) with LICOM_np. The analysis focused on the 2005 western North Pacific summer monsoon rainfall. The results showed that the regional coupled models with either RegCM4 or WRF4 as their atmospheric model component simulated the broad features over the WNP reasonably well. Quantitative intercomparison of the regional coupled simulations exhibited different biases for different climate variables. RegCM4_LICOM exhibited smaller biases in its simulation of the averaged June–July–August SST and rainfall, while WRF4_LICOM better captured the tropical cyclone (TC) intensity, the percentage contributions of rainfall induced by TCs to the total rainfall, and the diurnal cycle of rainfall and stratiform percentages, especially over land areas. The different behaviors in rainfall simulated by the two models were partly ascribed to the behaviors in the simulated western North Pacific subtropical high (WNPSH). The stronger (weaker) WNPSH in WRF4_LICOM (RegCM4_LICOM) was driven by overestimated (underestimated) diabatic heating, which peaked at approximately 450 hPa over the region around the Philippines in association with different condensation-radiation processes. Coupling of WRF4 with LIOCM is a crucial step towards the development of the next generation of regional earth system models at the Chinese Academy of Sciences.

The modern East Asian summer monsoon (EASM) features an extension from tropical to subtropical areas. However, the fundamental process that determines the northward extension of EASM in the geological history remains unclear. Here, we showed evidence from proxy data, climate modeling, and theoretical solutions that the northward extension of EASM to today's boundary emerged no later than the Miocene. The extension was driven by the monsoon seasonal march which features stepwise northward rainfall stages. The seasonal progression of monsoon was determined by Rossby wave responses from early summer to late summer and caused by the weakening of westerly jet colliding with the Tibetan Plateau (TP). The Rossby wave responses further led to a northward migration of the western Pacific subtropical high and thereby monsoon precipitation. Our findings propose a novel physical linkage between the geological evolution of EASM and the TP uplift in the context of monsoon seasonal march. The seasonal march of the modern East Asian summer monsoon, characterized as stepwise northward rainfall stages, is one unique feature and the most fundamental process of northward extension of East Asian summer monsoon. However, its geological history and controlling processes remain unknown. Here, we found that the seasonal progression of the monsoon emerged no later than the Miocene and was driven by the uplift of the Tibetan Plateau. The emergence of the seasonality has pushed the East Asian summer monsoon northward to today's boundary. Our results provide an essential understanding of the northward extension of the East Asian monsoon climate in geological history, highlighting the role of monsoon seasonal march. A novel physical linkage established between the East Asian monsoon climate and Tibetan Plateau uplift on the geological scaleOrographic forcing of the uplift of Tibetan Plateau determined the emergence of monsoon seasonal marchThe seasonal progression of the monsoon advanced further inland to the present boundary A novel physical linkage established between the East Asian monsoon climate and Tibetan Plateau uplift on the geological scale Orographic forcing of the uplift of Tibetan Plateau determined the emergence of monsoon seasonal march The seasonal progression of the monsoon advanced further inland to the present boundary

This paper provides a comparative analysis of the performance of a high-resolution regional ocean–atmosphere coupled model in predicting tropical cyclone (TC) gales over the northern South China Sea. The atmosphere and ocean components of the coupled system are represented by the China Meteorological Administration's Tropical Regional Atmosphere Model for the South China Sea (CMA-TRAMS) and the LASG/IAP Climate system Ocean Model (LICOM), respectively. The Ocean Atmosphere Sea Ice Soil VersionH 3 (OASIS3) software has been utilized for the exchange of momentum, heat, and freshwater fluxes between these two components. An assessment of the coupled model's three-day predictions for five TCs’ gales was conducted. Preliminary findings indicate that the predicted TC tracks show less sensitivity to oceanic influences than the predicted TC intensities. Significant improvement in predicting the surface TC gales has been achieved through coupling the ocean model. This improvement is attributed to the impact of the warmer ocean's effect on TC intensification, counteracting the cooling effect of the cold wake. In summary, coupling has enhanced the model's predictive capabilities for TC gales. A detailed assessment of the coupled model's performance in predicting other tropical weather phenomena is forthcoming.

A traceless-activation strategy for the synthesis of 4-arylchroman-2-ones via a Rh(III)-catalyzed C–H activation of 2-arylpyridines and subsequent conjugated/decarboxylative addition to coumarin-3-carboxylic acids has been reported. The carboxyl group at C3 position of coumarin proved to be crucial to realize the reaction, which is spontaneously removed after the reaction by the release of CO2. The reaction displayed good substrate tolerance and gave various 4-arylchroman-2-ones in up to 90% yield.

With anthropogenic global warming, heat‐related extreme events are projected to increase in severity and frequency. Already vulnerable regions like Africa will be hard‐hit. Therefore, such regions could benefit from low global warming levels. Using the Community Earth System Model low warming simulations, we investigate changes in temperature extremes across Africa as a function of global mean temperature in the context of the implications of the Paris Agreement's targets. A significant warming across Africa is projected at the 1.5 °C warming world and is amplified at the 2 °C world, exceeding the mean global warming rate. Specifically, North Africa and East Africa regions are projected to have the highest and lowest temperature changes of 0.63 °C (0.60–0.67 °C) and 0.50 °C (0.47–0.54 °C), respectively, between the 1.5 and 2 °C warmer worlds. Consequently, hot events are also estimated to increase with global warming. We showed that limiting warming to 1.5 °C instead of 2 °C may lead to 29% (27–31%) to 35% (33–37%) reduction in severity of hot events and to 31% (30–33%) to 42% (39–48%) reduction in the frequency of the threshold‐based high‐temperature events across Africa. The highest reductions are projected over North Africa. Furthermore, restricting warming to 0.5 °C lower than 2 °C might also result in 28% (34–40%) to 37% (25–34%) reduction in severity of once‐in‐10/20‐year heat events across Africa with North Africa having the highest benefits than tropical regions. Thus, restricting warming to low levels may indeed translate to substantial benefits of reduced intensity and frequency of extreme heat events across Africa. As global warming continue to increase extreme daily temperatures, efforts to limit this warming to low levels could be of much benefit to Africa, an already vulnerable populous region. Therefore, the agreed 1.5 and 2 °C global warming targets under the Paris Agreement might have substantial paybacks. Here, we used a suite of unique climate simulations to investigate differences in high‐temperature extremes under the 1.5 and 2 °C warming worlds across Africa. We found that limiting warming to 0.5 °C lower than 2 °C may lead to benefits of between 29% and 42% reductions in intensity and frequency of heat events across Africa, with the largest benefit estimated over North Africa. Currently, relatively rare once‐in‐20‐year heat events across Africa may become approximately twice as common under 2 °C world as compared to under 1.5 °C world. Therefore, limiting global warming to 1.5 °C instead of the previously suggested 2 °C could translate into substantial benefits across Africa. CESM low warming simulations are used to analyze mean and extreme high‐temperature events over Africa under 1.5 and 2 °C warming worldsCurrently, once‐in‐20‐year heat events across Africa may become approximately twice as common under 2 °C world than under 1.5 °C worldLimiting warming to 0.5 °C lower than 2 °C may lead to between 29% and 42% reductions in intensity and frequency of heat events across Africa

A practical and isoform-specific fluorescent probe based on BIDIPY dye have been designed, synthesized and well characterized for sensing CES1 activities in various biological systems such as living cells, tissues and zebrafish.

In this study, two limited‐area convection‐permitting models (ICON‐CPMs) and convection‐parameterized models (ICON‐CParMs) covering the Asia monsoon region from ICOsahedral Nonhydrostatic model are conducted to investigate the sensitivities of Mesoscale Convective Systems (MCSs) to convection configurations and horizontal resolutions. We find that ICON‐CPMs outperform ICON‐CParMs and ERA5 in number, lifetime, size, shape, orientation, effective speed, and MCS‐mean precipitation. Compared to the satellite observation, MCSs in ICON‐CParMs and ERA5 are oversized (30%–66%) and have longer (21%–29%) lifetimes but occur less (37%–46%) frequently. When turning off the convection scheme, performances are improved to a large extent. The underestimation of MCS‐mean precipitation rates in ICON‐CParMs and ERA5 are improved in ICON‐CPMs. Moisture budgets show that low‐level winds rather than moisture determine the strength of MCS‐mean precipitation rate. The strong low‐level convergence produces strong updrafts in ICON‐CPMs and eventually results in strong MCS precipitation. The overly intense convective precipitation of MCSs in CPMs is an inherent problem since the scale of convection triggered at the gray zone grid spacing is larger than that in the real world. Although the MCS‐mean precipitation rate is closer to the satellite observation in ICON‐CPMs, it is actually a compensation for overly strong convective precipitation and overly weak stratiform precipitation. Upgrading resolution from 8 to 4 km in ICON‐CPMs has benefits in simulating MCS lifetime, size, shape, orientation, and precipitation but not in MCS number. To investigate the simulation of Mesoscale Convective Systems (MCSs) at gray zone, we conduct three experiments with different convection configurations and horizontal resolutions. The results reveal that ICON convection‐permitting models (ICON‐CPMs) perform better in number, lifetime, size, shape, orientation, effective speed, and precipitation than ICON convection‐parameterized models (ICON‐CParMs). Notably, the underestimations of MCS‐mean precipitation rate by ERA5 and ICON‐CParMs are improved in ICON‐CPMs, although the better performance is the outcome of compensation between the too strong convective precipitation and too weak stratiform precipitation in ICON‐CPMs. The too strong convective precipitation can be attributed to low‐level winds rather than moisture, while the too weak stratiform precipitation is caused by excessive dry grids. Furthermore, improving resolution from 8 to 4 km in ICON‐CPMs yields benefits in lifetime, size, shape, orientation, and especially precipitation (convective and stratiform precipitation rates, area sizes, fluxes, and their evolutions) but not in MCS number. The findings of this study have important implications for the accurate simulation and prediction of MCSs and their impacts. Convection‐permitting models (CPMs) outperform convection‐parameterized ones in simulating basic, morphology and precipitation properties of Mesoscale Convective Systems (MCSs)The 8 km ICON CPMs can capture MCS features and upgrading resolution to 4 km can improve the simulation furtherOverly strong MCS convective precipitation and overly weak stratiform precipitation in CPMs is an inherent problem Convection‐permitting models (CPMs) outperform convection‐parameterized ones in simulating basic, morphology and precipitation properties of Mesoscale Convective Systems (MCSs) The 8 km ICON CPMs can capture MCS features and upgrading resolution to 4 km can improve the simulation further Overly strong MCS convective precipitation and overly weak stratiform precipitation in CPMs is an inherent problem

Climate system models are useful tools for understanding the interactions among the components of the climate system and predicting/projecting future climate change. The development of climate models has been a central focus of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences (LASG/IAP) since the establishment of the laboratory in 1985. In China, many pioneering component models and fully coupled models of the climate system have been developed by LASG/IAP. The fully coupled climate system developed in the recent decade is named FGOALS (Flexible Global Ocean‐Atmosphere‐Land System Model). In this paper, an application‐oriented review of the LASG/IAP FGOALS model is presented. The improved model performances are demonstrated in the context of cloud‐radiation processes, Asian monsoon, ENSO phenomena, Atlantic Meridional Overturning Circulation (AMOC) and sea ice. The FGOALS model has contributed to both CMIP5 (Coupled Model Intercomparison Project‐phase 5) and IPCC (Intergovernmental Panel on Climate Change) AR5 (the Fifth Assessment Report). The release of FGOALS data has supported the publication of nearly 500 papers around the world. The results of FGOALS are cited ~106 times in the IPCC WG1 (Working Group 1) AR5. In addition to the traditional long‐term simulations and projections, near‐term decadal climate prediction is a new set of CMIP experiment, progress of LAGS/IAP in the development of near‐term decadal prediction system is reviewed. The FGOALS model has supported many Chinese national‐level research projects and contributed to the national climate change assessment report. The crucial role of FGOALS as a modeling tool for supporting climate sciences is highlighted by demonstrating the model's performances in the simulation of the evolution of Earth's climate from the past to the future.

In this paper, the features and possible causes of sea surface temperature (SST) biases over the Northwest Pacific are investigated based on a mixed-layer heat budget analysis in 21 coupled general circulation models (CGCMs) from phase 5 of the Coupled Model Inter-comparison Project (CMIP5). Most CMIP5 models show cold SST biases throughout the year over the Northwest Pacific. The largest biases appear during summer, and the smallest biases occur during winter. These cold SST biases are seen at the basin scale and are mainly located in the inner region of the low and mid-latitudes. According to the mixed-layer heat budget analysis, overestimation of upward net sea surface heat fluxes associated with atmospheric processes are primarily responsible for the cold SST biases. Among the different components of surface heat fluxes, overestimated upward latent heat fluxes induced by the excessively strong surface winds contribute the most to the cold SST biases during the spring, autumn, and winter seasons. Conversely, during the summer, overestimated upward latent heat fluxes and underestimated downward solar radiations at the sea surface are equally important. Further analysis suggests that the overly strong surface winds over the Northwest Pacific during winter and spring are associated with excessive precipitation over the Maritime Continent region, whereas those occurring during summer and autumn are associated with the excessive northward extension of the intertropical convergence zone (ITCZ). The excessive precipitation over the Maritime Continent region and the biases in the simulated ITCZ induce anomalous northeasterlies, which are in favor of enhancing low-level winds over the North Pacific. The enhanced surface wind increases the sea surface evaporation, which contributes to the excessive upward latent heat fluxes. Thus, the SST over the Northwest Pacific cools.

Anthropogenic forcing is anticipated to increase the magnitude and frequency of extreme events1 , the impacts of which will be particularly hard-felt in already vulnerable locations such as Africa2 . However, projected changes in African climate extremes remain little explored, particularly in the context of the Paris Agreement targets3,4. Here, using Community Earth System Model low warming simulations5 , we examine how heat and hydrological extremes may change in Africa under stabilized 1.5 °C and 2 °C scenarios, focusing on the projected changing likelihood of events that have comparable magnitudes to observed record-breaking seasons. In the Community Earth System Model, limiting end-of-century warming to 1.5 °C is suggested to robustly reduce the frequency of heat extremes compared to 2 °C. In particular, the probability of events similar to the December–February 1991/1992 southern African and 2009/2010 North African heat waves is estimated to be reduced by 25 ±5% and 20 ±4%, respectively, if warming is limited to 1.5 °C instead of 2 °C. For hydrometeorological extremes (that is, drought and heavy precipitation), by contrast, signal differences are indistinguishable from the variation between ensemble members. Thus, according to this model, continued efforts to limit warming to 1.5 °C offer considerable benefits in terms of minimizing heat extremes and their associated socio-economic impacts across Africa. The record hot year of 2015 in Africa had devastating impacts. The likelihood of future annual temperature extremes over Africa exceeding those of 2015 are 91% and 100% in 1.5 °C and 2 °C worlds, respectively, stressing the benefits of limiting future anthropogenic warming.

Extreme high‐temperature events have large socioeconomic and human health impacts. East Asia (EA) is a populous region, and it is crucial to assess the changes in extreme high‐temperature events in this region under different climate change scenarios. The Community Earth System Model low‐warming experiment data were applied to investigate the changes in the mean and extreme high temperatures in EA under 1.5°C and 2°C warming conditions above preindustrial levels. The results show that the magnitude of warming in EA is approximately 0.2°C higher than the global mean. Most populous subregions, including eastern China, the Korean Peninsula, and Japan, will see more intense, more frequent, and longer‐lasting extreme temperature events under 1.5°C and 2°C warming. The 0.5°C lower warming will help avoid 35%–46% of the increases in extreme high‐temperature events in terms of intensity, frequency, and duration in EA with maximal avoidance values (37%–49%) occurring in Mongolia. Thus, it is beneficial for EA to limit the warming target to 1.5°C rather than 2°C. Extreme heats continue to occur as global warming continues in the last several decades. These natural disasters can lead to illnesses and deaths of people and animals and great economic losses. The Paris Agreement called for limiting the global warming bellow 2°C and pursuing efforts to limit it to 1.5°C compared with preindustrial levels. We used a set of simulations to investigate the changes of the mean temperature and extreme heats in 1.5°C and 2°C warmer climates in East Asia and the benefits of limiting global warming to 1.5°C rather than 2°C. We find that the mean warming of East Asia is about 0.2°C higher than global mean. Most densely populated subregions, including eastern China, the Korean Peninsula, and Japan, will see larger extreme heats increase than the other subregions of East Asia. Compared with the 2°C warming climate, the increasing of extreme heats will be reduced over one third in the 1.5°C warming climate. Changes in the mean and extreme high temperatures over East Asia in response to warmings of 1.5°C and 2°C were quantified using the recently released NCAR CESM low‐warming experiment dataMost densely populated subregions, including eastern China, the Korean Peninsula, and Japan, will see larger increases in extreme high‐temperature events than the other subregions of East Asia in terms of intensity, frequency, and duration under 1.5°C and 2°C warmingThe 0.5°C lower warming will help avoid 35%‐46% of the increases in the frequency, intensity, and duration of extreme high‐temperature events in East Asia with maximal avoidance values (37%‐49%) occurring in Mongolia

The Coupled Model Intercomparison Project (CMIP) is an international community-based infrastructure that supports climate model intercomparison, climate variability, climate prediction, and climate projection. Improving the performance of climate models over East Asia and the western North Pacific has been a challenge for the climate-modeling community. In this paper, we provide a synthesis robustness analysis of the climate models participating in CMIP-Phase 5 (CMIP5). The strengths and weaknesses of the CMIP5 models are assessed from the perspective of climate mean state, interannual variability, past climate change during the mid-Pliocene (MP) and the last millennium, and climate projection. The added values of regional climate models relative to the driving global climate models are also assessed. Although an encouraging increase in credibility and an improvement in the simulation of mean states, interannual variability, and past climate changes are visible in the progression from CMIP3 to CMIP5, some previously noticed biases such as the ridge position of the western North Pacific subtropical high and the associated rainfall bias are still evident in CMIP5 models. Weaknesses are also evident in simulations of the interannual amplitude, such as El Niño-Southern Oscillation (ENSO)-monsoon relationships. Coupled models generally show better results than standalone atmospheric models in simulating both mean states and interannual variability. Multi-model intercomparison indicates significant uncertainties in the future projection of climate change, although precipitation increases consistently across models constrained by the Clausius-Clapeyron relation. Regional ocean-atmosphere coupled models are recommended for the dynamical downscaling of climate change projections over the East Asia-western North Pacific domain.

In this study, esculetin(1) was chosen as a lead compound and some structural modifications were designed to explore the antioxidant activities of esculetin derivatives. Meanwhile, a convenient method for selective methylation of catechol coumarins with different bases was developed. Furthermore, a few 5,7-dihydroxylcoumarins were synthesized and 7-hydroxylcoumarins were employed in order to explore the potential structure-antioxidant activity relationships. The antioxidant activities of these compounds were evaluated and compared with standard antioxidant Trolox by the 2,2′-diphenyl-1-picrylhydrazyl(DPPH) assay, 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonate) cation(ABTS+) assay and ferric reducing antioxidant power(FRAP) assay. The results show that the catechol group is the key pharmacophore. Meanwhile, introducing electronegative groups at the C4 position of esculetin(1) may enhance the antioxidative capacity, while introducing a group containing nitrogen as a hydrogen bond acceptor at the C8 position may slightly reduce the antioxidative capacity. Among them, the most powerful antioxidants are com-pounds 5and 7, which exhibit higher antioxidant activity than esculetin(1) in all assays.

An expedient and efficient method for selective methylation of catechol coumarins by working with different alkalis under appropriate reaction conditions is reported. Esculetins were selectively methylated at position 6 and position 7 in good yield using CH3I in the presence of NaH and Na2CO3, respectively. However, daphnetins showed less regioselectivity under the same reaction conditions. Furthermore, the site preference for the methylation reaction was interpreted by the density functional theory at B3LYP/6-31+G(d) level.

The aim of this study is to compare X-ray mammography (MG) and ultrasonography (US) in the diagnosis of breast diseases in Chinese women. We retrospectively analyzed X-ray mammograms of 274 patients with US and surgical/pathological results of breast diseases diagnosed at The Second Affiliated Hospital of Anhui Medical University (Hefei, China) between March 2011 and November 2014. The MG and US data were compared to surgical records using the results from post-surgical pathological examinations as the gold standard. The overall sensitivity, specificity, accuracy, false-positive, false-negative, positive predictive value, and negative predictive value for the detection of breast cancer were 88.5%, 57.9%, 73.7%, 42.1%, 11.5%, 69.2%, and 82.5%, respectively, for MG and 95.9%, 66.7%, 81.8%, 33.3%, 4.1%, 75.5%, and 93.8%, respectively, for US. Of the 274 cases, lesion size by MG agreed with surgery in 133 (48.5%) patients compared with 216 (78.8%) by US (P< 0.01). Lesion location by MG agreed with surgery in 146 (53.3%) patients compared with 257 (93.8%) by US (P< 0.01). These values were then stratified according to age, menstrual status, breast density, and breast volume, and the agreement rates of MG with surgery were lower than that of US (all P< 0.01), except when the lesion size was >5 cm (P> 0.05). US was better than MG in the preoperative evaluation of breast diseases of Chinese women. These results suggest that US could be more useful for detecting breast lesions in China, especially for younger women with dense breasts.

The reproducibility and future changes of the onset of the Asian summer monsoon were analyzed based on the simulations and projections under the Representative Concentration Pathways (RCP) scenario in which anthropogenic emissions continue to rise throughout the 21st century (i.e. RCP8.5) by all realizations from four Chinese models that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Delayed onset of the monsoon over the Arabian Sea was evident in all simulations for present-day climate, which was associated with a too weak simulation of the low-level Somali jet in May. A consistent advanced onset of the monsoon was found only over the Arabian Sea in the projections, where the advanced onset of the monsoon was accompanied by an increase of rainfall and an anomalous anticyclone over the northern Indian Ocean. In all the models except FGOALS-g2, the enhanced low-level Somali jet transported more water vapor to the Arabian Sea, whereas in FGOALS-g2 the enhanced rainfall was determined more by the increased wind convergence. Furthermore, and again in all models except FGOALS-g2, the equatorial SST warming, with maximum increase over the eastern Pacific, enhanced convection in the central West Pacific and reduced convection over the eastern Indian Ocean and Maritime Continent region, which drove the anomalous anticyclonic circulation over the western Indian Ocean. In contrast, in FGOALS-g2, there was minimal (near-zero) warming of projected SST in the central equatorial Pacific, with decreased convection in the central West Pacific and enhanced convection over the Maritime Continent. The broader-scale differences among the models across the Pacific were related to both the differences in the projected SST pattern and in the present-day simulations.

Using the reanalysis data and 20th century simulation of coupled model FGOALS_gl developed by LASG/IAP, we identified two distinct interannual modes of Northwestern Pacific Subtropical Anticyclone (NWPAC) by performing Empirical Orthogonal Function (EOF) analysis on 850 hPa wind field over the northwestern Pacific in summer. Based on the associated anomalous equatorial zonal wind, these two modes are termed as “Equatorial Easterly related Mode” (EEM) and “Equatorial Westerly related Mode” (EWM), respectively. The formation mechanisms of these two modes are similar, whereas the maintenance mechanisms, dominant periods, and the relationships with ENSO are different. The EEM is associated with El Niño decaying phase, with the anomalous anticyclone established in the preceding winter and persisted into summer through local positive air-sea feedback. By enhancing equatorial upwelling of subsurface cold water, EEM favors the transition of ENSO from El Niño to La Niña. The EWM is accompanied by the El Niño events with long persistence, with the anomalous anticyclone formed in spring and strengthened in summer due to the warm Sea Surface Temperature anomalies (SSTA) forcing from the equatorial central-eastern Pacific. The model well reproduces the spatial patterns of these two modes, but fails to simulate the percentage variance accounted for by the two modes. In the NCEP reanalysis (model result), EEM (EWM) appears as the first mode, which accounts for 35.6% (68.2%) of the total variance.Using the reanalysis data and 20th century simulation of coupled model FGOALS_gl developed by LASG/IAP, we identified two distinct interannual modes of Northwestern Pacific Subtropical Anticyclone (NWPAC) by performing Empirical Orthogonal Function (EOF) analysis on 850 hPa wind field over the northwestern Pacific in summer. Based on the associated anomalous equatorial zonal wind, these two modes are termed as “Equatorial Easterly related Mode” (EEM) and “Equatorial Westerly related Mode” (EWM), respectively. The formation mechanisms of these two modes are similar, whereas the maintenance mechanisms, dominant periods, and the relationships with ENSO are different. The EEM is associated with El Niño decaying phase, with the anomalous anticyclone established in the preceding winter and persisted into summer through local positive air-sea feedback. By enhancing equatorial upwelling of subsurface cold water, EEM favors the transition of ENSO from El Niño to La Niña. The EWM is accompanied by the El Niño events with long persistence, with the anomalous anticyclone formed in spring and strengthened in summer due to the warm Sea Surface Temperature anomalies (SSTA) forcing from the equatorial central-eastern Pacific. The model well reproduces the spatial patterns of these two modes, but fails to simulate the percentage variance accounted for by the two modes. In the NCEP reanalysis (model result), EEM (EWM) appears as the first mode, which accounts for 35.6% (68.2%) of the total variance.

Multi-decadal high resolution simulations over the CORDEX East Asia domain were performed with the regional climate model RegCM3 nested within the Flexible Global Ocean-Atmosphere-Land System model, Grid-point Version 2 (FGOALS-g2). Two sets of simulations were conducted at the resolution of 50 km, one for present day (1980–2005) and another for near-future climate (2015–40) under the Representative Concentration Pathways 8.5 (RCP8.5) scenario. Results show that RegCM3 adds value with respect to FGOALS-g2 in simulating the spatial patterns of summer total and extreme precipitation over China for present day climate. The major deficiency is that RegCM3 underestimates both total and extreme precipitation over the Yangtze River valley. The potential changes in total and extreme precipitation over China in summer under the RCP8.5 scenario were analyzed. Both RegCM3 and FGOALS-g2 results show that total and extreme precipitation tend to increase over northeastern China and the Tibetan Plateau, but tend to decrease over southeastern China. In both RegCM3 and FGOALS-g2, the change in extreme precipitation is weaker than that for total precipitation.

Abstract: A regional ocean atmosphere coupled model (ROAM) is developed through coupler OASIS3, and is composed of regional climate model RegCM3 and CREM (Climate version of Regional Eta Model) as its atmospheric component and of a revised Princeton ocean model (POM2000) as its oceanic component. The performance of the ROAM over the western North Pacific summer monsoon region is assessed by the case simulation of warm season in 1998. Impacts of different atmospheric model components on the performance of ROAM are investigated. Compared with stand-alone simulation, CREM (RegCM3) produces more (or less) rainfall over ocean area with inclusion of the air-sea coupling. Different biases of rainfall are caused by the different biases of SST derived from the coupled simulation. Warm (or cold) SST bias simulated by CREM_CPL (RegCM3_CPL) increases (or decreases) the evaporation at sea surface, then increases (or decreases) the rainfall over ocean. The analyses suggest that the biases of vertical profile of temperature and specific humidity in stand-alone simulations may be responsible for the SST biases in regional coupled simulations. Compared with reanalysis data, the warmer (or colder) and moister (or dryer) lower troposphere simulated in CREM (RegCM3) produces less (or more) sea surface latent heat flux. Meanwhile, the more unstable (or stable) lower troposphere produces less (or more) cloudiness at low-level, which increases (or decreases) the solar radiation reaching on the sea surface. CREM (RegCM3) forced by observed SST overestimates (or underestimates) the sea surface net heat flux, implying a potential warm (or cold) heat source. After coupling with POM2000, the warm (or cold) heat source would further increase (or decrease) the SST. The biases of vertical profile of temperature and specific humidity may be ascribed to the different representation of cumulus convection in atmospheric models.

The Tibetan Plateau (TP) is known as Asian Water Tower and its atmospheric water cycle has been a lasting challenge to climate modeling community. Here, we compare two sets of the Met Office Unified Model simulations—one is a convection‐parameterized version (large‐scale model; LSM) and the other is a convection‐permitting model (CPM) simulation. The added value of the CPM in terms of atmospheric water cycle process is analyzed, including external moisture transport, fraction of atmospheric water vapor converting to precipitation and the precipitation recycle ratio. Results show that the simulated TP precipitation and evaporation for the summer of 2009 is significantly improved in the CPM. First, the overestimation of atmospheric water cycle by LSM is improved in CPM due to a reasonable representation of the fraction of atmospheric water vapor converting to precipitation. The overestimation of precipitation recycle ratio also indicates the LSM generates excessive convection compared to the CPM and therefore has a larger wet bias over the TP. Second, a better simulation of local precipitation has feedback on the circulation. Compared with the LSM, the less moisture convergence in the CPM is dominated by the stronger outflow through the eastern edge of the TP rather than the weaker inflow, implying the upscale effects of the resolved moist convection on the moisture transport over the TP. Our results imply that the CPM is a useful tool in the reproduction of moisture transport and atmospheric water cycle process over the Asian Water Tower and other regions of the world with complex topography. The atmospheric water cycle over the Tibetan Plateau (TP, also as known as the Asian Water Tower) has been a challenge to climate models with convection parameterization. Benefiting from the high enough resolution, convection‐permitting model (CPM) can explicitly resolve the deep convection and therefore reduce the bias related with the convection parameterization scheme. Here, we compare a CPM with its low resolution version that employs convection‐parameterization in simulating atmospheric water cycle process over the TP. We find the precipitation and evaporation over the TP is significantly improved in the CPM. There is more water vapor flowing out of the TP and less water vapor in the atmosphere converting into the precipitation in the CPM, resulting in a reduced wet bias. CPM is free from the constrains of the convection parameterization scheme and therefore depicts the atmospheric water cycle over the TP better. The convection‐permitting model (CPM) better reproduces precipitation over the Tibetan Plateau than convection‐parameterized model (large‐scale model [LSM])The overestimation of atmospheric water cycle by LSM is improved in CPM simulationThe interaction between large‐scale circulation and convection further reduces moisture convergence and wet bias in the CPM The convection‐permitting model (CPM) better reproduces precipitation over the Tibetan Plateau than convection‐parameterized model (large‐scale model [LSM]) The overestimation of atmospheric water cycle by LSM is improved in CPM simulation The interaction between large‐scale circulation and convection further reduces moisture convergence and wet bias in the CPM

This study compared statistical downscaling model (SD) and dynamical downscaling model (DD) for changes in extreme temperature and precipitation indices, driven by the same global climate model output, in the 1.5 and 2 °C warmer climates in China. Simple bias correction (BC) methods were used to correct the climatology of temperature and precipitation in both models. After BC, both models show comparable performance in reproducing the spatial distributions of the extreme temperature and precipitation indices. Corrected model data were used to analyze future changes. Changing patterns of the extreme temperature indices are similar in the two models. Compared with the 2 °C warmer climate, warming 0.5 °C less can help reduce about 6% of summer day (SU) and 11% of tropical night (TR) increases (relative to 1986–2005) in China. Specifically, the reduced values of TR in northwest and northeast China are larger than 30% and 70%, respectively, in both models. Extreme wet indices will increase in most parts of China in the warmer climates. In DD, 5‐day maximum precipitation (RX5day) will increase by approximately 10% and 14% in the 1.5 and 2 °C warmer climates, respectively, with maximal values (17% and 28%, respectively) occurring in north China. In SD, differences in extreme wet indices between the two warmer climates are small, and RX5day will increase more than 20% in northeast China. In DD, specific humidity will increase, and the East Asian summer monsoon will be enhanced in the warmer climates, favoring a larger increase in wet extremes in north China compared to other parts of east China. Statistical and dynamical downscaling methods are used to analyze extreme climate event changes in China in the 1.5 and 2 °C warmer climatesBias correction methods aimed at correcting the climatology of temperatures and precipitation are applied to both modelsChanging patterns of temperature indices are similar between the two models in the two warmer climates