Usage of methods for determination of long-term trends of the dynamics of vegetation formation on the background of climate changes becomes more and more important at modern stage of the assessment of natural systems ...Usage of methods for determination of long-term trends of the dynamics of vegetation formation on the background of climate changes becomes more and more important at modern stage of the assessment of natural systems development. This causes to researchers a series of problems from choice of conceptual base to notions and terms of the processes identified and of state of vegetation of different environments. Solution of such a task results inevitably in necessity to correct the understanding of existing processes occurring in the vegetation cover. It allows establishing a direction of their development in the system of natural factors of any territory. As a result, we have base for determination of age, site and role of current state of phytocenoses in successional systems. It is necessary for this to reveal the peculiarities of phytocenoses composition and formation due to climate dynamics and to determine a period of ecosystems homeostasis, especially for phytocenoses of contact natural conditions. Optimal values of phytocenoses diversity, like one of whole biosystems, depend on the amount of resource in the environment, on stability degree and on evolutional development of cenoses due to ecological, micro-evolutional and evolutional processes.展开更多
Tropical basin interactions and the climatic linkages between mid-to-high latitudes and the tropics are active research areas.These interactions include the influence of El Niño-Southern Oscillation(ENSO)on the t...Tropical basin interactions and the climatic linkages between mid-to-high latitudes and the tropics are active research areas.These interactions include the influence of El Niño-Southern Oscillation(ENSO)on the tropical Indian and Atlantic oceans,the feedback from these basins on ENSO,the influence of the tropics on mid-to-high-latitude climates,and the feedback from higher latitudes on tropical climate variability.This review summarizes the current understanding of these relationships and key underlying physical processes.展开更多
In this article,we address both recent advances and open questions in some mathematical and computational issues in geophysical fluid dynamics(GFD)and climate dynamics.The main focus is on 1)the primitive equations(PE...In this article,we address both recent advances and open questions in some mathematical and computational issues in geophysical fluid dynamics(GFD)and climate dynamics.The main focus is on 1)the primitive equations(PEs)models and their related mathematical and computational issues,2)climate variability,predictability and successive bifurcation,and 3)a new dynamical systems theory and its applications to GFD and climate dynamics.展开更多
In this paper, a climate dynamics model with the effects of topography and a non-constant external force, which consists of the Navier-Stokes equations and a temperature equation arising from the evolution process of ...In this paper, a climate dynamics model with the effects of topography and a non-constant external force, which consists of the Navier-Stokes equations and a temperature equation arising from the evolution process of the atmosphere, was considered.Under certain assumptions imposed on the initial data and by using some delicate estimates and compactness arguments, we proved the L^1-stability of weak solutions to the atmospheric equations.展开更多
The Arctic plays a pivotal role in the Earth’s climate system,with its rapid transformation exerting profound impacts on global climate dynamics,ecosystems,and human societies.In recent decades,Arctic warming has sig...The Arctic plays a pivotal role in the Earth’s climate system,with its rapid transformation exerting profound impacts on global climate dynamics,ecosystems,and human societies.In recent decades,Arctic warming has significantly outpaced the global mean temperature increase,driving the enhanced sea ice decline,the accelerated mass loss of the Greenland Ice Sheet,permafrost degradation,and glacier retreat.These changes modulate atmospheric and oceanic circulation patterns,establishing teleconnections with mid-and low-latitude climate systems.Investigating the historical evolution,current state,and projected future trends of the Arctic climate system,as well as its global impacts,is crucial for elucidating the mechanisms underlying Arctic amplification,refining climate change projections,attributing extreme weather and climate events,and informing sustainable development strategies.展开更多
Based on the citrus temperature, precipitation, sunlight and climate risk degree, the article divides subtropics of China into three types： the low risk region, the moderate risk region and the high risk region. The ...Based on the citrus temperature, precipitation, sunlight and climate risk degree, the article divides subtropics of China into three types： the low risk region, the moderate risk region and the high risk region. The citrus temperature risk increases with increasing latitude （except for the western mountainous area of subtropics of China）. The citrus precipitation risk in the central part of subtropics of China is higher than that in the northern and western parts. The distributions of citrus sunlight risk are not consistent to those of the citrus precipitation risk. The citrus climate risk is mainly influenced by temperature. There is latitudinal zonal law for the distribution of the climate risk, that is, the climate risk increases with increasing latitude At the same time the climate risk in mountainous area is high and that in eastern plain area is low. There are differences in the temporal and spatial changes of the citrus climate. In recent 46 years, the citrus climate risk presents a gradual increasing trend in subtropics of China, especially it has been increasing fast since the 1980s. Because of the global warming, the low risk region in the eastern and southern parts has a gradual decreasing trend, however, the high risk region in the northern and western parts has an increasing trend and the high risk region has been extending eastward and southward. The article analyses the distribution of the citrus climate risk degree of reduction rates of 〉10%, 〉20% and 〉30% in subtropics of China, and studies their changes in different time periods. Results show that the risk is increasing from southeast to northwest.展开更多
Regional climate simulation can generally be improved by using an RCM nested within a coarser-resolution GCM.However, whether or not it can also be improved by the direct use of a state-of-the-art GCM with very fine r...Regional climate simulation can generally be improved by using an RCM nested within a coarser-resolution GCM.However, whether or not it can also be improved by the direct use of a state-of-the-art GCM with very fine resolution, close to that of an RCM, and, if so, which is the better approach, are open questions. These questions are important for understanding and using these two kinds of simulation approaches, but have not yet been investigated. Accordingly, the present reported work compared simulation results over China from a very-fine-resolution GCM（VFRGCM） and from RCM dynamical downscaling. The results showed that：（1） The VFRGCM reproduces the climatologies and trends of both air temperature and precipitation, as well as inter-monthly variations of air temperature in terms of spatial pattern and amount, closer to observations than the coarse-resolution version of the GCM. This is not the case, however, for the inter-monthly variations of precipitation.（2） The VFRGCM captures the climatology, trend, and inter-monthly variation of air temperature, as well as the trend in precipitation, more reasonably than the RCM dynamical downscaling method.（3） The RCM dynamical downscaling method performs better than the VFRGCM in terms of the climatology and inter-monthly variation of precipitation. Overall,the results suggest that VFRGCMs possess great potential with regard to their application in climate simulation in the future,and the RCM dynamical downscaling method is still dominant in terms of regional precipitation simulation.展开更多
The Changbai Mountains and the Appalachian Mountains have similar spatial contexts.The elevation,latitude,and moisture gradients of both mountain ranges offer regional insight for investigating the vegetation dynamics...The Changbai Mountains and the Appalachian Mountains have similar spatial contexts.The elevation,latitude,and moisture gradients of both mountain ranges offer regional insight for investigating the vegetation dynamics in eastern Eurasia and eastern North America.We determined and compared the spatial patterns and temporal trends in the normalized difference vegetation index(NDVI)in the Changbai Mountains and the Appalachian Mountains using time series data from the Global Inventory Modeling and Mapping Studies 3^(rd) generation dataset from 1982 to 2013.The spatial pattern of NDVI in the Changbai Mountains exhibited fragmentation,whereas NDVI in the Appalachian Mountains decreased from south to north.The vegetation dynamics in the Changbai Mountains had an insignificant trend at the regional scale,whereas the dynamics in the Appalachian Mountains had a significant increasing trend.NDVI increased in 55% of the area of the Changbai Mountains and in 95% of the area of the Appalachian Mountains.The peak NDVI occurred one month later in the Changbai Mountains than in the Appalachian Mountains.The results revealed a significant increase in NDVI in autumn in both mountain ranges.The climatic trend in the Changbai Mountains included warming and decreased precipitation,and whereas that in the Appalachian Mountains included significant warming and increased precipitation.Positive and negative correlations existed between NDVI and temperature and precipitation,respectively,in both mountain ranges.Particularly,the spring temperature and NDVI exhibited a significant positive correlation in both mountain ranges.The results of this study suggest that human actives caused the differences in the spatial patterns of NDVI and that various characteristics of climate change and intensity of human actives dominated the differences in the NDVI trends between the Changbai Mountains and the Appalachian Mountains.Additionally,the vegetation dynamics of both mountain ranges were not identical to those in previous broader-scale studies.展开更多
A nested-model system is constructed by embedding the regional climate model RegCM3 into a general circulation model for monthly-scale regional climate forecast over East China. The systematic errors are formulated fo...A nested-model system is constructed by embedding the regional climate model RegCM3 into a general circulation model for monthly-scale regional climate forecast over East China. The systematic errors are formulated for the region on the basis of 10-yr (1991-2000) results of the nested-model system, and of the datasets of the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) and the temperature analysis of the National Meteorological Center (NMC), U.S.A., which are then used for correcting the original forecast by the system for the period 2001-2005. After the assessment of the original and corrected forecasts for monthly precipitation and surface air temperature, it is found that the corrected forecast is apparently better than the original, suggesting that the approach can be applied for improving monthly-scale regional climate dynamical forecast.展开更多
Efficient and accurate prediction of ocean surface latent heat fluxes is essential for understanding and modeling climate dynamics.Conventional estimation methods have low resolution and lack accuracy.The transformer ...Efficient and accurate prediction of ocean surface latent heat fluxes is essential for understanding and modeling climate dynamics.Conventional estimation methods have low resolution and lack accuracy.The transformer model,with its self-attention mechanism,effectively captures long-range dependencies,leading to a degradation of accuracy over time.Due to the non-linearity and uncertainty of physical processes,the transformer model encounters the problem of error accumulation,leading to a degradation of accuracy over time.To solve this problem,we combine the Data Assimilation(DA)technique with the transformer model and continuously modify the model state to make it closer to the actual observations.In this paper,we propose a deep learning model called TransNetDA,which integrates transformer,convolutional neural network and DA methods.By combining data-driven and DA methods for spatiotemporal prediction,TransNetDA effectively extracts multi-scale spatial features and significantly improves prediction accuracy.The experimental results indicate that the TransNetDA method surpasses traditional techniques in terms of root mean square error and R2 metrics,showcasing its superior performance in predicting latent heat fluxes at the ocean surface.展开更多
Arid central Asia,encompassing Northwest China and Central Asia,constitutes the world’s largest azonal arid region.The climatic dynamics of this region are primarily influenced by the strength and position of the wes...Arid central Asia,encompassing Northwest China and Central Asia,constitutes the world’s largest azonal arid region.The climatic dynamics of this region are primarily influenced by the strength and position of the westerly circulation[1].Arid central Asia is characterized by a distinctive basin-mountain geomorphological structure,which creates pronounced environmental contrasts.The intermontane basins are extremely arid,with extensive deserts that rank among the most prolific dust emission zones in the Northern Hemisphere.In contrast,the mountainous regions are rainy and humid,with abundant water resources that support oasis agriculture and civilization.展开更多
Dear Editor,Coral reefs sustain high biodiversity and have been referred to as the rainforests of the ocean.However,anthropogenic stressors have led to a global decline of coral reefs,partly due to the increasing scal...Dear Editor,Coral reefs sustain high biodiversity and have been referred to as the rainforests of the ocean.However,anthropogenic stressors have led to a global decline of coral reefs,partly due to the increasing scale,frequency,and intensity of coral bleaching events driven by global warming(Henley et al.,2024;Hughes et al.,2018).展开更多
Precise forecasts of wildfire danger are crucial for proactive fuel management and emergency responses,yet they pose a challenge at the subseasonal scale due to limitations in prediction capabilities and a gap between...Precise forecasts of wildfire danger are crucial for proactive fuel management and emergency responses,yet they pose a challenge at the subseasonal scale due to limitations in prediction capabilities and a gap between forecast outputs and the needs of decision-makers.This study introduces an innovative hybrid modeling framework that integrates artificial intelligence(AI)with climate dynamic prediction systems to accurately forecast High Fire-Danger Days(HFDDs)for the following month.These HFDDs are derived from historical satellite fire data and the optimum fire danger index,with a particular focus on Southwest China as a case study.The AI module,based on the ResNet-18 neural network model,integrates observational and physically constrained analysis to establish links between HFDDs and optimal predictors of atmospheric circulation from both the concurrent and preceding months.Leveraging climate dynamical forecasting,this hybrid model provides more reliable deterministic predictions for monthly HFDDs than conventional methods that rely solely on terrestrial variables such as precipitation.More importantly,the integration of dynamical ensemble prediction enhances the model’s capability for skillful probabilistic predictions of HFDDs,facilitating the creation of customized fire danger outlooks and emergency action maps tailored to stakeholders’needs.The model’s added economic value was also evaluated,demonstrating its potential to improve decision-making in disaster management and bridge the“last-mile gap”in climate service delivery.This work contributes to the Seamless Prediction and Services for Sustainable Natural and Built Environment(SEPRESS)Program(2025–32),under the United Nations Educational Scientific and Cultural Organization(UNESCO)International Decade of Sciences for Sustainable Development(2024–33).展开更多
In May 2008, ScienceWatch.com named Advances in Atmospheric Sciences a Rising Star among Geosciences journals. According to Essential Science IndicatorsSM from Thomson Reuters, the journal＇s cur-rent citation record ...In May 2008, ScienceWatch.com named Advances in Atmospheric Sciences a Rising Star among Geosciences journals. According to Essential Science IndicatorsSM from Thomson Reuters, the journal＇s cur-rent citation record includes 764 papers cited a total of 1,658 times between January 1, 1998 and February 29 2008.展开更多
A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment （GRACE） K-Band Range Rate （KBRR） data based on dynamic integral approach is presented in this pa...A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment （GRACE） K-Band Range Rate （KBRR） data based on dynamic integral approach is presented in this paper. After meticulously preprocessing of the GRACE KBRR data, the root mean square of its post residuals is about 0.2 micrometers per second, and seventy-two monthly temporal solutions truncated to degree and order 60 are computed for the period from January 2003 to December 2008. After applying the combi- nation filter in WHU-Grace01s, the global temporal signals show obvious periodical change rules in the large-scale fiver basins. In terms of the degree variance, our solution is smaller at high degrees, and shows a good consistency at the rest of degrees with the Release 05 models from Center for Space Research （CSR）, GeoForschungsZentrum Potsdam （GFZ） and Jet Pro- pulsion Laboratory 0PL）. Compared with other published models in terms of equivalent water height distribution, our solution is consistent with those published by CSR, GFZ, JPL, Delft institute of Earth Observation and Space system （DEOS）, Tongji University （Tongji）, Institute of Theoretical Geodesy （ITG）, Astronomical Institute in University of Bern （AIUB） and Groupe de Recherche de Geodesie Spatiale （GRGS}, which indicates that the accuracy of WHU-Grace01s has a good consistency with the previously published GRACE solutions.展开更多
The period of the 70s and 80s was marked by a drought in the Sahelian coun-tries.However,since the beginning of the 21st century,these countries have experienced a resurgence of heavy rainfall and devastating floods,c...The period of the 70s and 80s was marked by a drought in the Sahelian coun-tries.However,since the beginning of the 21st century,these countries have experienced a resurgence of heavy rainfall and devastating floods,causing in-estimable socio-economic damage and losses.The objective of this work is to study the dynamics of atmospheric conditions associated with seventeen ex-treme rainfall events listed in the database of the Directorate of Civil Protection of Senegal and having caused significant socio-economic impacts between 2000 and 2017.This study was carried out using satellite products and atmospheric reanalysis data.The results of the analyses of the various atmospheric parame-ters studied show,at the synoptic scale,that extreme rainfall events are mainly modulated by African easterly waves.Strong moisture transport convergences in the lower tropospheric layers due to vortices associated with these waves are recorded.A response of this moisture convergence in the lower layers accom-panied by vertical moisture transport is highlighted by strong anomalies and wind divergence.This configuration corresponds to the presence of a vertically well-structured convective system.The analysis of atmospheric parameters such as relative vorticity,wind,relative humidity and precipitable water shows that they are good indicators to characterize rainfall extremes.The behavior of the anomalies of these variables shows the presence of a significant amount of moisture in the tropospheric column and the most marked pressure levels are between 850 and 700-hPa,and in the upper layers around 200-hPa.展开更多
In 2020,China announced the"emission peak,carbon neutrality"policy,that is,China aims to have CO2 emissions peak before 2030 and achieve carbon neutrality before 2060.The scenario of carbon neutrality will b...In 2020,China announced the"emission peak,carbon neutrality"policy,that is,China aims to have CO2 emissions peak before 2030 and achieve carbon neutrality before 2060.The scenario of carbon neutrality will be significantly distinguished from the scenario we experienced since the industrial revolution.However,instrumental data are unavailable in the future carbon-neutral scenario.Earth system models and climate dynamics theory are needed to comprehend and project the climate change.In this paper,we illustrate our perspective of the issues related to"emission peak,carbon neutrality",including climate dynamics,climate-carbon feedback,interaction between China and global climate and carbon emissions and solutions,etc.We highlight that climate change has profoundly affected human production and life.The frequent occurrence of extreme weather disasters in recent years,together with the impact of epidemics,make the future"carbon peak&carbon-neutral"scenario more complex.There is whopping uncertainty but also a massive challenge to the scientific community.Thus,carbon neutrality is closely related to domestic production and lives,and there is little time left for planning.We believe that we will make a breakthrough in climate dynamics in the context of carbon neutrality with our joint efforts,which will serve our country’s carbon emission policy at different stages.展开更多
The examination of fluctuations in the correlations betweenδ13C andδ18O is of significant importance for the reconstruction of the Earth's climate history.A key challenge in paleoclimatology is finding a suitabl...The examination of fluctuations in the correlations betweenδ13C andδ18O is of significant importance for the reconstruction of the Earth's climate history.A key challenge in paleoclimatology is finding a suitable method to represent the correlated fluctuation system betweenδ13C andδ18O.The method must be able to handle data sets with missing or inaccurate values,while still retaining the full range of dynamic information about the system.The non-linear and complex correlations betweenδ13C andδ18O poses a chal-lenge in developing reliable and interpretable approaches.The transition network,which involves embedding theδ13C andδ18O sequence into the network using phase space reconstruction,is a coarse-grained based approach.This approach is well-suited to nonlinear,complex dynamic systems,and is particularly adept at emerging knowledge from low-quality datasets.We have effectively represented the fluctuations in the correlation betweenδ13C andδ18O since 66 million years ago(Ma)using a system of complex network.This system,which has topological dynamical structures,is able to uncover the stable modes and key patterns in Cenozoic climate dynamics.Our findings could help to improve climate models and predictions of future climate change.展开更多
Using an improved CCM1/NCAR climate dynamic model and a combination distribution of land-ocean-vegetation during 40-50 MaBP,a series of numerical experiments representing different stages of the Tibetan Plateau uplift...Using an improved CCM1/NCAR climate dynamic model and a combination distribution of land-ocean-vegetation during 40-50 MaBP,a series of numerical experiments representing different stages of the Tibetan Plateau uplifting and different land-ocean distributions are designed to discuss the influence of the Plateau uplifting and land-ocean distribution variation on Asian climate change.It is shown that Tibetan Plateau uplifting can firstly increase the precipitation in China during the period from initial uplift to half height of modern Tibetan Plateau and then decrease the rainfall during the time from the half height to the present plateau.At the same time. the uplifting can reduce surface air temperature over China.Besides.the effects of the uplift and land-ocean distribution change on the variation of winter and summer Asian monsoon circulation are also discussed.展开更多
The coastal plain of Laizhou Bay in Bohai Sea is a transitional area of land-sea interaction.Sediments in this area can bear significant information of sea-level fluctuation,climate change,as well as regional geologic...The coastal plain of Laizhou Bay in Bohai Sea is a transitional area of land-sea interaction.Sediments in this area can bear significant information of sea-level fluctuation,climate change,as well as regional geological setting.Here,in this study,new sporopollen data from three boreholes(GK138,GK111 and GK95)in the coastal plain of Laizhou Bay,Bohai Sea were investigated,and the pollen spectrum since the late middle Pleistocene was established as six sporopollen assemblage zones(Ⅰ-Ⅵ),i.e.,Pinus-Quercus-Artemisia,Gramineae-Artemisia-Chenopodiaceae,Picea-Pinus-QuercusArtemisia,Picea-Pinus-Betula-Gramineae-Artemisia,Picea-Pinus-Cupressaceae-Chenopodiaceae and Pinus-Quercus-Gramineae-Artemisia-Chenopodiaceae.Combining with existing sedimentary successions and detailed radiocarbon dating results of the sediments from the three boreholes,paleovegetation and climatic evolution since the late middle Pleistocene were reconstructed.The findings revealed that climatic changes in this area since the late middle Pleistocene were characterized by alternating cold-arid and warmhumid conditions,which were well correlated with marine isotopic stages(MIS).The present study offers specific insight into the climatic dynamics in the North China Plain since the late middle Pleistocene and provides evidence of a clear link among the palynoflora in the area,the glacial-interglacial period climatedriven sea-level changes,and the marineδ^(18)O records.展开更多
文摘Usage of methods for determination of long-term trends of the dynamics of vegetation formation on the background of climate changes becomes more and more important at modern stage of the assessment of natural systems development. This causes to researchers a series of problems from choice of conceptual base to notions and terms of the processes identified and of state of vegetation of different environments. Solution of such a task results inevitably in necessity to correct the understanding of existing processes occurring in the vegetation cover. It allows establishing a direction of their development in the system of natural factors of any territory. As a result, we have base for determination of age, site and role of current state of phytocenoses in successional systems. It is necessary for this to reveal the peculiarities of phytocenoses composition and formation due to climate dynamics and to determine a period of ecosystems homeostasis, especially for phytocenoses of contact natural conditions. Optimal values of phytocenoses diversity, like one of whole biosystems, depend on the amount of resource in the environment, on stability degree and on evolutional development of cenoses due to ecological, micro-evolutional and evolutional processes.
基金stimulated by the summer school and workshop on"Theory,Mechanisms and Hierarchical Modeling of Climate Dynamics:Atlantic Variability and Tropical Basin Interactions at Interannual to Multi-Decadal Timescales",which was hosted by ICTP and jointly funded by US CLIVAR,NSF,NOAA,NASA,CLIVAR,and ICTPA.H.was supported by the Regional and Global Model Analysis(RGMA)component of the Earth and Environmental System Modeling Program of the U.S.Department of Energy's Office of Biological&Environmental Research(BER),via the National Science Foundation(NSF)IA 1947282(DE-SC0022070)+8 种基金The National Center for Atmospheric Research is sponsored by the NSF of the United States of America under Cooperative Agreement No.1852977.A.V.F.and B.S.F.are supported by the"Make our planet great again"program(ANR-18-MPGA-0001,France)A.V.F.was also supported by grants from the NSF(AGS-205309),NOAA(NA20OAR4310377),NASA(80NSSC21K0558),and U.S.Department of Energy(DESC0023134,DE-SC0024186)A.B.is supported by the Italian Ministry of Education,University and Research(MIUR)through the JPI Oceans and JPI Climate"Next Generation Climate Science in Europe for Oceans",ROADMAP Project(D.M.593/2016)N.K.acknowledges the support from the Trond Mohn Foundation(grant BFS2018TMT01)and the Research Council of Norway(grant 328935)B.S.F.acknowledges support from the European Union as part of the EPOC project(Explaining and Predicting the Ocean Conveyor,grant number:101059547)D.M.and N.K.were partially funded by the JPI Climate&JPI Oceans ROADMAP Project(593/2016)the European Union's Horizon Europe Impetus4Change project(101081555)I.R.was supported by the Japan Society for the Promotion of Science through a Grant-in-Aid for Scientific Research(KAKENHI)(grant no.JP23K25946)the Kyushu University Program for Collaborative Research(grant no.2024CR-AO-2).
文摘Tropical basin interactions and the climatic linkages between mid-to-high latitudes and the tropics are active research areas.These interactions include the influence of El Niño-Southern Oscillation(ENSO)on the tropical Indian and Atlantic oceans,the feedback from these basins on ENSO,the influence of the tropics on mid-to-high-latitude climates,and the feedback from higher latitudes on tropical climate variability.This review summarizes the current understanding of these relationships and key underlying physical processes.
基金the grants from the Office of Naval Research,from the National Science Foundation,and from the National Nature Science Foundation of China(40325013,40675046)。
文摘In this article,we address both recent advances and open questions in some mathematical and computational issues in geophysical fluid dynamics(GFD)and climate dynamics.The main focus is on 1)the primitive equations(PEs)models and their related mathematical and computational issues,2)climate variability,predictability and successive bifurcation,and 3)a new dynamical systems theory and its applications to GFD and climate dynamics.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41630530, 41575109 & 91230202)
文摘In this paper, a climate dynamics model with the effects of topography and a non-constant external force, which consists of the Navier-Stokes equations and a temperature equation arising from the evolution process of the atmosphere, was considered.Under certain assumptions imposed on the initial data and by using some delicate estimates and compactness arguments, we proved the L^1-stability of weak solutions to the atmospheric equations.
文摘The Arctic plays a pivotal role in the Earth’s climate system,with its rapid transformation exerting profound impacts on global climate dynamics,ecosystems,and human societies.In recent decades,Arctic warming has significantly outpaced the global mean temperature increase,driving the enhanced sea ice decline,the accelerated mass loss of the Greenland Ice Sheet,permafrost degradation,and glacier retreat.These changes modulate atmospheric and oceanic circulation patterns,establishing teleconnections with mid-and low-latitude climate systems.Investigating the historical evolution,current state,and projected future trends of the Arctic climate system,as well as its global impacts,is crucial for elucidating the mechanisms underlying Arctic amplification,refining climate change projections,attributing extreme weather and climate events,and informing sustainable development strategies.
基金National Natural Sciences Foundation of China,No.40771033Special Item Funds of Climate Change Supported by China Meteorological Administration,No.CCSF-09-11
文摘Based on the citrus temperature, precipitation, sunlight and climate risk degree, the article divides subtropics of China into three types： the low risk region, the moderate risk region and the high risk region. The citrus temperature risk increases with increasing latitude （except for the western mountainous area of subtropics of China）. The citrus precipitation risk in the central part of subtropics of China is higher than that in the northern and western parts. The distributions of citrus sunlight risk are not consistent to those of the citrus precipitation risk. The citrus climate risk is mainly influenced by temperature. There is latitudinal zonal law for the distribution of the climate risk, that is, the climate risk increases with increasing latitude At the same time the climate risk in mountainous area is high and that in eastern plain area is low. There are differences in the temporal and spatial changes of the citrus climate. In recent 46 years, the citrus climate risk presents a gradual increasing trend in subtropics of China, especially it has been increasing fast since the 1980s. Because of the global warming, the low risk region in the eastern and southern parts has a gradual decreasing trend, however, the high risk region in the northern and western parts has an increasing trend and the high risk region has been extending eastward and southward. The article analyses the distribution of the citrus climate risk degree of reduction rates of 〉10%, 〉20% and 〉30% in subtropics of China, and studies their changes in different time periods. Results show that the risk is increasing from southeast to northwest.
基金jointly supported by the National Natural Science Foundation of China (Grant Nos. 41130103, 41421004 and 41405087)
文摘Regional climate simulation can generally be improved by using an RCM nested within a coarser-resolution GCM.However, whether or not it can also be improved by the direct use of a state-of-the-art GCM with very fine resolution, close to that of an RCM, and, if so, which is the better approach, are open questions. These questions are important for understanding and using these two kinds of simulation approaches, but have not yet been investigated. Accordingly, the present reported work compared simulation results over China from a very-fine-resolution GCM（VFRGCM） and from RCM dynamical downscaling. The results showed that：（1） The VFRGCM reproduces the climatologies and trends of both air temperature and precipitation, as well as inter-monthly variations of air temperature in terms of spatial pattern and amount, closer to observations than the coarse-resolution version of the GCM. This is not the case, however, for the inter-monthly variations of precipitation.（2） The VFRGCM captures the climatology, trend, and inter-monthly variation of air temperature, as well as the trend in precipitation, more reasonably than the RCM dynamical downscaling method.（3） The RCM dynamical downscaling method performs better than the VFRGCM in terms of the climatology and inter-monthly variation of precipitation. Overall,the results suggest that VFRGCMs possess great potential with regard to their application in climate simulation in the future,and the RCM dynamical downscaling method is still dominant in terms of regional precipitation simulation.
基金supported by the National Natural Science Foundation of China (Grant No. 41601438 and 41571078)the Fundamental Research Funds for the Central Universities (Grant No.2412016KJ026)the Foundation of the Education Department of Jilin Province in the 13~(th) Five-Year project (Grant No. JJKH20170916KJ)
文摘The Changbai Mountains and the Appalachian Mountains have similar spatial contexts.The elevation,latitude,and moisture gradients of both mountain ranges offer regional insight for investigating the vegetation dynamics in eastern Eurasia and eastern North America.We determined and compared the spatial patterns and temporal trends in the normalized difference vegetation index(NDVI)in the Changbai Mountains and the Appalachian Mountains using time series data from the Global Inventory Modeling and Mapping Studies 3^(rd) generation dataset from 1982 to 2013.The spatial pattern of NDVI in the Changbai Mountains exhibited fragmentation,whereas NDVI in the Appalachian Mountains decreased from south to north.The vegetation dynamics in the Changbai Mountains had an insignificant trend at the regional scale,whereas the dynamics in the Appalachian Mountains had a significant increasing trend.NDVI increased in 55% of the area of the Changbai Mountains and in 95% of the area of the Appalachian Mountains.The peak NDVI occurred one month later in the Changbai Mountains than in the Appalachian Mountains.The results revealed a significant increase in NDVI in autumn in both mountain ranges.The climatic trend in the Changbai Mountains included warming and decreased precipitation,and whereas that in the Appalachian Mountains included significant warming and increased precipitation.Positive and negative correlations existed between NDVI and temperature and precipitation,respectively,in both mountain ranges.Particularly,the spring temperature and NDVI exhibited a significant positive correlation in both mountain ranges.The results of this study suggest that human actives caused the differences in the spatial patterns of NDVI and that various characteristics of climate change and intensity of human actives dominated the differences in the NDVI trends between the Changbai Mountains and the Appalachian Mountains.Additionally,the vegetation dynamics of both mountain ranges were not identical to those in previous broader-scale studies.
基金National Natural Science Foundation of China (40875067, 40675040)Knowledge Innovation Program of the Chinese Academy of Sciences (IAP09306)National Basic Research Program of China. (2006CB400505)
文摘A nested-model system is constructed by embedding the regional climate model RegCM3 into a general circulation model for monthly-scale regional climate forecast over East China. The systematic errors are formulated for the region on the basis of 10-yr (1991-2000) results of the nested-model system, and of the datasets of the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) and the temperature analysis of the National Meteorological Center (NMC), U.S.A., which are then used for correcting the original forecast by the system for the period 2001-2005. After the assessment of the original and corrected forecasts for monthly precipitation and surface air temperature, it is found that the corrected forecast is apparently better than the original, suggesting that the approach can be applied for improving monthly-scale regional climate dynamical forecast.
基金The National Natural Science Foundation of China under contract Nos 42176011 and 61931025the Fundamental Research Funds for the Central Universities of China under contract No.24CX03001A.
文摘Efficient and accurate prediction of ocean surface latent heat fluxes is essential for understanding and modeling climate dynamics.Conventional estimation methods have low resolution and lack accuracy.The transformer model,with its self-attention mechanism,effectively captures long-range dependencies,leading to a degradation of accuracy over time.Due to the non-linearity and uncertainty of physical processes,the transformer model encounters the problem of error accumulation,leading to a degradation of accuracy over time.To solve this problem,we combine the Data Assimilation(DA)technique with the transformer model and continuously modify the model state to make it closer to the actual observations.In this paper,we propose a deep learning model called TransNetDA,which integrates transformer,convolutional neural network and DA methods.By combining data-driven and DA methods for spatiotemporal prediction,TransNetDA effectively extracts multi-scale spatial features and significantly improves prediction accuracy.The experimental results indicate that the TransNetDA method surpasses traditional techniques in terms of root mean square error and R2 metrics,showcasing its superior performance in predicting latent heat fluxes at the ocean surface.
基金supported by the Excellent Research Group Program for Tibetan Plateau Earth System(42588201)the National Key Research and Development Program of China(2023YFF0725005)+2 种基金the TPESER Youth Innovation Key Program(TPESER-QNCX2022ZD-04)the National Natural Science Foundation of China(42401048)the China Postdoctoral Innovation Program(GZC20241804).
文摘Arid central Asia,encompassing Northwest China and Central Asia,constitutes the world’s largest azonal arid region.The climatic dynamics of this region are primarily influenced by the strength and position of the westerly circulation[1].Arid central Asia is characterized by a distinctive basin-mountain geomorphological structure,which creates pronounced environmental contrasts.The intermontane basins are extremely arid,with extensive deserts that rank among the most prolific dust emission zones in the Northern Hemisphere.In contrast,the mountainous regions are rainy and humid,with abundant water resources that support oasis agriculture and civilization.
基金supported by the National Natural Science Foundation of China(42122045,U23A2036)the National Key Research and Development Program of China(2022-24,2023YFC3108800)。
文摘Dear Editor,Coral reefs sustain high biodiversity and have been referred to as the rainforests of the ocean.However,anthropogenic stressors have led to a global decline of coral reefs,partly due to the increasing scale,frequency,and intensity of coral bleaching events driven by global warming(Henley et al.,2024;Hughes et al.,2018).
基金J.YANG was supported by funding from the National Natural Science Foundation of China(Grant Nos.42475022,42261144671)the National Key R&D Program of China(Project No.2024YFC3013100)+2 种基金the Fundamental Research Funds for the Central UniversitiesM.LU was supported by the Otto Poon Centre of Climate Resilience and Sustainability at HKUST and the Hong Kong Research Grant Committee(Project No.16300424)Data processing and storage were supported by the National Key Scientific and Technological Infrastructure project“Earth System Numerical Simulation Facility”(EarthLab).
文摘Precise forecasts of wildfire danger are crucial for proactive fuel management and emergency responses,yet they pose a challenge at the subseasonal scale due to limitations in prediction capabilities and a gap between forecast outputs and the needs of decision-makers.This study introduces an innovative hybrid modeling framework that integrates artificial intelligence(AI)with climate dynamic prediction systems to accurately forecast High Fire-Danger Days(HFDDs)for the following month.These HFDDs are derived from historical satellite fire data and the optimum fire danger index,with a particular focus on Southwest China as a case study.The AI module,based on the ResNet-18 neural network model,integrates observational and physically constrained analysis to establish links between HFDDs and optimal predictors of atmospheric circulation from both the concurrent and preceding months.Leveraging climate dynamical forecasting,this hybrid model provides more reliable deterministic predictions for monthly HFDDs than conventional methods that rely solely on terrestrial variables such as precipitation.More importantly,the integration of dynamical ensemble prediction enhances the model’s capability for skillful probabilistic predictions of HFDDs,facilitating the creation of customized fire danger outlooks and emergency action maps tailored to stakeholders’needs.The model’s added economic value was also evaluated,demonstrating its potential to improve decision-making in disaster management and bridge the“last-mile gap”in climate service delivery.This work contributes to the Seamless Prediction and Services for Sustainable Natural and Built Environment(SEPRESS)Program(2025–32),under the United Nations Educational Scientific and Cultural Organization(UNESCO)International Decade of Sciences for Sustainable Development(2024–33).
文摘In May 2008, ScienceWatch.com named Advances in Atmospheric Sciences a Rising Star among Geosciences journals. According to Essential Science IndicatorsSM from Thomson Reuters, the journal＇s cur-rent citation record includes 764 papers cited a total of 1,658 times between January 1, 1998 and February 29 2008.
基金supported by the National 973Program of China(2013CB733302)the National Natural Science Foundation of China(41131067,41174020,41374023,41474019)+2 种基金the Open Research Fund Program of the State Key Laboratory of Geodesy and Earth's Dynamics(SKLGED2015-1-3-E)the open fund of State Key Laboratory of Geographic Information Engineering(SKLGIE2013-M-1-3)the open fund of Key Laboratory of Geospace Environment and Geodesy,Ministry of Education(13-02-05)
文摘A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment （GRACE） K-Band Range Rate （KBRR） data based on dynamic integral approach is presented in this paper. After meticulously preprocessing of the GRACE KBRR data, the root mean square of its post residuals is about 0.2 micrometers per second, and seventy-two monthly temporal solutions truncated to degree and order 60 are computed for the period from January 2003 to December 2008. After applying the combi- nation filter in WHU-Grace01s, the global temporal signals show obvious periodical change rules in the large-scale fiver basins. In terms of the degree variance, our solution is smaller at high degrees, and shows a good consistency at the rest of degrees with the Release 05 models from Center for Space Research （CSR）, GeoForschungsZentrum Potsdam （GFZ） and Jet Pro- pulsion Laboratory 0PL）. Compared with other published models in terms of equivalent water height distribution, our solution is consistent with those published by CSR, GFZ, JPL, Delft institute of Earth Observation and Space system （DEOS）, Tongji University （Tongji）, Institute of Theoretical Geodesy （ITG）, Astronomical Institute in University of Bern （AIUB） and Groupe de Recherche de Geodesie Spatiale （GRGS}, which indicates that the accuracy of WHU-Grace01s has a good consistency with the previously published GRACE solutions.
文摘The period of the 70s and 80s was marked by a drought in the Sahelian coun-tries.However,since the beginning of the 21st century,these countries have experienced a resurgence of heavy rainfall and devastating floods,causing in-estimable socio-economic damage and losses.The objective of this work is to study the dynamics of atmospheric conditions associated with seventeen ex-treme rainfall events listed in the database of the Directorate of Civil Protection of Senegal and having caused significant socio-economic impacts between 2000 and 2017.This study was carried out using satellite products and atmospheric reanalysis data.The results of the analyses of the various atmospheric parame-ters studied show,at the synoptic scale,that extreme rainfall events are mainly modulated by African easterly waves.Strong moisture transport convergences in the lower tropospheric layers due to vortices associated with these waves are recorded.A response of this moisture convergence in the lower layers accom-panied by vertical moisture transport is highlighted by strong anomalies and wind divergence.This configuration corresponds to the presence of a vertically well-structured convective system.The analysis of atmospheric parameters such as relative vorticity,wind,relative humidity and precipitable water shows that they are good indicators to characterize rainfall extremes.The behavior of the anomalies of these variables shows the presence of a significant amount of moisture in the tropospheric column and the most marked pressure levels are between 850 and 700-hPa,and in the upper layers around 200-hPa.
基金This work was supported by the National Natural Science Foundation of China(Grants No.42141019,41831175,91937302,and 41721004)Key Deployment Project of Centre for Ocean Mega-Research of Science,Chinese academy of science(Grant No.COMS2019Q03)Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA20060501).
文摘In 2020,China announced the"emission peak,carbon neutrality"policy,that is,China aims to have CO2 emissions peak before 2030 and achieve carbon neutrality before 2060.The scenario of carbon neutrality will be significantly distinguished from the scenario we experienced since the industrial revolution.However,instrumental data are unavailable in the future carbon-neutral scenario.Earth system models and climate dynamics theory are needed to comprehend and project the climate change.In this paper,we illustrate our perspective of the issues related to"emission peak,carbon neutrality",including climate dynamics,climate-carbon feedback,interaction between China and global climate and carbon emissions and solutions,etc.We highlight that climate change has profoundly affected human production and life.The frequent occurrence of extreme weather disasters in recent years,together with the impact of epidemics,make the future"carbon peak&carbon-neutral"scenario more complex.There is whopping uncertainty but also a massive challenge to the scientific community.Thus,carbon neutrality is closely related to domestic production and lives,and there is little time left for planning.We believe that we will make a breakthrough in climate dynamics in the context of carbon neutrality with our joint efforts,which will serve our country’s carbon emission policy at different stages.
基金supported by 2022 Subject Development Research Fund Project of China University of Geosciences,Beijing(Grant No.2022XK211)2023 Graduate Innovation Fund Project of China University of Geosciences,Beijing(Grant No.YB2023YC014)supported by the National Natural Science Foundation of China(Grant No.42174149 and No.42272134).
文摘The examination of fluctuations in the correlations betweenδ13C andδ18O is of significant importance for the reconstruction of the Earth's climate history.A key challenge in paleoclimatology is finding a suitable method to represent the correlated fluctuation system betweenδ13C andδ18O.The method must be able to handle data sets with missing or inaccurate values,while still retaining the full range of dynamic information about the system.The non-linear and complex correlations betweenδ13C andδ18O poses a chal-lenge in developing reliable and interpretable approaches.The transition network,which involves embedding theδ13C andδ18O sequence into the network using phase space reconstruction,is a coarse-grained based approach.This approach is well-suited to nonlinear,complex dynamic systems,and is particularly adept at emerging knowledge from low-quality datasets.We have effectively represented the fluctuations in the correlation betweenδ13C andδ18O since 66 million years ago(Ma)using a system of complex network.This system,which has topological dynamical structures,is able to uncover the stable modes and key patterns in Cenozoic climate dynamics.Our findings could help to improve climate models and predictions of future climate change.
基金under the auspices of the National(G199800)Chinese Academy of Sciences'Key Project for Basic Research on Tibetan Plateau(kz951-A1-204:kz95T-06).
文摘Using an improved CCM1/NCAR climate dynamic model and a combination distribution of land-ocean-vegetation during 40-50 MaBP,a series of numerical experiments representing different stages of the Tibetan Plateau uplifting and different land-ocean distributions are designed to discuss the influence of the Plateau uplifting and land-ocean distribution variation on Asian climate change.It is shown that Tibetan Plateau uplifting can firstly increase the precipitation in China during the period from initial uplift to half height of modern Tibetan Plateau and then decrease the rainfall during the time from the half height to the present plateau.At the same time. the uplifting can reduce surface air temperature over China.Besides.the effects of the uplift and land-ocean distribution change on the variation of winter and summer Asian monsoon circulation are also discussed.
基金supported by the Taishan Scholar Foundation of Shandong Province,China(Grant No.20190954)the National Natural Science Foundation of China(Grant No.32101373)+1 种基金the Shandong Provincial Natural Science Foundation,China(Grant No.ZR2020QC050)the State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,CAS,China(Grant No.123104)。
文摘The coastal plain of Laizhou Bay in Bohai Sea is a transitional area of land-sea interaction.Sediments in this area can bear significant information of sea-level fluctuation,climate change,as well as regional geological setting.Here,in this study,new sporopollen data from three boreholes(GK138,GK111 and GK95)in the coastal plain of Laizhou Bay,Bohai Sea were investigated,and the pollen spectrum since the late middle Pleistocene was established as six sporopollen assemblage zones(Ⅰ-Ⅵ),i.e.,Pinus-Quercus-Artemisia,Gramineae-Artemisia-Chenopodiaceae,Picea-Pinus-QuercusArtemisia,Picea-Pinus-Betula-Gramineae-Artemisia,Picea-Pinus-Cupressaceae-Chenopodiaceae and Pinus-Quercus-Gramineae-Artemisia-Chenopodiaceae.Combining with existing sedimentary successions and detailed radiocarbon dating results of the sediments from the three boreholes,paleovegetation and climatic evolution since the late middle Pleistocene were reconstructed.The findings revealed that climatic changes in this area since the late middle Pleistocene were characterized by alternating cold-arid and warmhumid conditions,which were well correlated with marine isotopic stages(MIS).The present study offers specific insight into the climatic dynamics in the North China Plain since the late middle Pleistocene and provides evidence of a clear link among the palynoflora in the area,the glacial-interglacial period climatedriven sea-level changes,and the marineδ^(18)O records.
