In November 1984,China launched its first expedition to the Southern Ocean and the Antarctic continent,culminating in the establishment of its first year-round research station—Great Wall Station—on the Antarctic Pe...In November 1984,China launched its first expedition to the Southern Ocean and the Antarctic continent,culminating in the establishment of its first year-round research station—Great Wall Station—on the Antarctic Peninsula in February 1985.Forty years later,in February 2024,China’s fifth research station,Qinling Station,commenced operations on Inexpress-ible Island near Terra Nova Bay.展开更多
During the recent four decades since 1980,a series of modern climate satellites were launched,allowing for the measurement and record-keeping of multiple climate parameters,especially over the polar regions where trad...During the recent four decades since 1980,a series of modern climate satellites were launched,allowing for the measurement and record-keeping of multiple climate parameters,especially over the polar regions where traditional observations are difficult to obtain.China has been actively engaging in polar expeditions.Many observations were conducted during this period,accompanied by improved Earth climate models,leading to a series of insightful understandings concerning Arctic and Antarctic climate changes.Here,we review the recent progress China has made concerning Arctic and Antarctic climate change research over the past decade.The Arctic temperature increase is much higher than the global-mean warming rate,associated with a rapid decline in sea ice,a phenomenon called the Arctic Amplification.The Antarctic climate changes showed a zonally asymmetric pattern over the past four decades,with most of the fastest changes occurring over West Antarctica and the Antarctic Peninsula.The Arctic and Antarctic climate changes were driven by anthropogenic greenhouse gas emissions and ozone loss,while tropical-polar teleconnections play important roles in driving the regional climate changes and extreme events over the polar regions.Polar climate changes may also feedback to the entire Earth climate system.The adjustment of the circulation in both the troposphere and the stratosphere contributed to the interactions between the polar climate changes and lower latitudes.Climate change has also driven rapid Arctic and Southern ocean acidification.Chinese researchers have made a series of advances in understanding these processes,as reviewed in this paper.展开更多
Long-term survival of 116 leukemia/MDS patients received allo-SCT conditioned by a regimen with ATG-F or without ATG-F was analysed, together with the impact of ATG-F on the long-term survival, GVHD and disease relaps...Long-term survival of 116 leukemia/MDS patients received allo-SCT conditioned by a regimen with ATG-F or without ATG-F was analysed, together with the impact of ATG-F on the long-term survival, GVHD and disease relapse. Seventy patients received an ATG-F containing conditioning regimen FBCA, and 46 patients received a non-ATG-F FBC regimen. The FBCA regimen was associated with a 5-year survival of 65.4% in the complete HLA-matched group and 39.3% in the HLA-mismatched group. The difference between the two groups was significant (P = 0.012). For the FBC conditioning regimen, the 5-year overall survival of HLA-matched patients and the HLA-mismatched patients was 34.2% and 24.2% respectively (P = 0.216). The incidence of cGVHD was 32.9% and 83.6% in the FBCA and FBC condition regimen group respectively. Only 2.9% of the cases showed extensive cGVHD in the FBCA group while it was 69.4% in the FBC group (P = 0.00). Multivariate analysis indicated that relapse was related to the disease status and HLA typing, but unrelated to the conditioning regimens whether or not ATG-F was used (HR 0.54, P = 0.109). We conclude that the addition of ATG-F to conditioning regimen favours the longterm survival of allo-SCT.展开更多
This paper provides a brief summary of the representative research outcomes on the Arctic-midlatitude connection since the founding of the Chinese Meteorological Society in 1924.(1)The revelation of the North Atlantic...This paper provides a brief summary of the representative research outcomes on the Arctic-midlatitude connection since the founding of the Chinese Meteorological Society in 1924.(1)The revelation of the North Atlantic Oscillation,the Arctic Oscillation,and the Arctic Dipole anomaly represents three significant milestones in the study of large-scale Arctic-midlatitude teleconnections.(2)Before the mid-1990s,Chinese researchers revealed the key pathways by which Arctic cold air affects cold wave processes in East Asia,the key areas for cold waves,and the dynamical processes of cold high pressure during cold waves.These findings are prominent representatives of Arctic-midlatitude connection research and have profoundly influenced the development of meteorology in China and the prediction of cold wave processes in winter.(3)The melting of Arctic sea ice and Arctic warming anomalies influence midlatitude weather events and climate variations by affecting the evaporation of water vapor from the ocean surface,turbulent heat flux between atmosphere and ocean,meridional temperature gradient of the atmosphere,zonal winds,the location and intensity of the storm track,and propagation of large-scale horizontal teleconnection patterns and planetary waves between the troposphere and stratosphere.(4)The melting of Arctic sea ice plays important roles in modulating interdecadal variations of the winter atmospheric circulation,leading to alternative occurrence of a warm Arctic-cold Eurasia(2004/05-2012/13)and a warm Arctic-warm Eurasia(2013/14-2018/19).The former strengthens the connection between the Arctic and midlatitudes,while the latter corresponds to a noticeable weakening of the Arctic-midlatitude connection.(5)The melting of Arctic sea ice facilitates the frequent occurrence of Arctic cold anomalies in the middle and lower troposphere during summer,leading to the formation of blocking circulation anomalies in high-latitude regions that are conducive to the occurrence of heatwaves and wildfires in some regions of high-latitudes.(6)The frequency of summer heatwaves averaged from the Qinghai-Xizang Plateau to the mid and low latitude areas of eastern China has a direct dynamical link with the frequent occurrence of summer Arctic cold anomalies in the middle and lower troposphere.The systematic northward shift of the tropospheric zonal winds over East Asia is the intrinsic mechanism that connects the Arctic cold anomalies with the heatwaves in East Asia.Future research on Arctic-midlatitude connection should pay more attention to the role of Arctic sea ice melting in the low-frequency variability of atmospheric circulation,particularly emphasizing the impacts of both different spatial anomalies and anomalous amplitudes in Arctic sea ice concentrations.It is necessary to quantitatively examine the role of Arctic sea ice melting in extreme weather and climate events.展开更多
Variations of winter Arctic sea ice bordering on the North Atlantic are closely related to climate variations in the same region. When winter North Atlantic Oscillation (NAO) index is positive (negative) anomaly phase...Variations of winter Arctic sea ice bordering on the North Atlantic are closely related to climate variations in the same region. When winter North Atlantic Oscillation (NAO) index is positive (negative) anomaly phase, Icelandic Low is obviously deepened and shifts northwards (southwards). Simultaneously, the Subtropical High over the North Atlantic is also intensified, and moves northwards (southwards). Those anomalies strengthen (weaken) westerly between Icelandic Low and the Subtropical High, and further result in positive (negative) sea surface temperature (SST) anomalies in the mid-latitude of the North Atlantic, and increase (decrease) the warm water transportation from the mid-latitude to the Barents Sea, which causes positive (negative) mixed-layer water temperature anomalies in the south part of the Barents Sea. Moreover, the distribution of anomaly air temperature clearly demonstrates warming (cooling) in northern Europe and the subarctic regions (including the Barents Sea) and cooling展开更多
The Chinese Academy of Meteorological Sciences Climate System Model(CAMS-CSM) is a newly developed global climate model that will participate in the Coupled Model Intercomparison Project phase 6. Based on historical s...The Chinese Academy of Meteorological Sciences Climate System Model(CAMS-CSM) is a newly developed global climate model that will participate in the Coupled Model Intercomparison Project phase 6. Based on historical simulations(1900-2013), we evaluate the model performance in simulating the observed characteristics of the Arctic climate system, which includes air temperature, precipitation, the Arctic Oscillation(AO), ocean temperature/salinity,the Atlantic meridional overturning circulation(AMOC), snow cover, and sea ice. The model-data comparisons indicate that the CAMS-CSM reproduces spatial patterns of climatological mean air temperature over the Arctic(60°-90°N) and a rapid warming trend from 1979 to 2013. However, the warming trend is overestimated south of the Arctic Circle, implying a subdued Arctic amplification. The distribution of climatological precipitation in the Arctic is broadly captured in the model, whereas it shows limited skills in depicting the overall increasing trend. The AO can be reproduced by the CAMS-CSM in terms of reasonable patterns and variability. Regarding the ocean simulation, the model underestimates the AMOC and zonally averaged ocean temperatures and salinity above a depth of 500 m, and it fails to reproduce the observed increasing trend in the upper ocean heat content in the Arctic. The largescale distribution of the snow cover extent(SCE) in the Northern Hemisphere and the overall decreasing trend in the spring SCE are captured by the CAMS-CSM, while the biased magnitudes exist. Due to the underestimation of the AMOC and the poor quantification of air–sea interaction, the CAMS-CSM overestimates regional sea ice and underestimates the observed decreasing trend in Arctic sea–ice area in September. Overall, the CAMS-CSM reproduces a climatological distribution of the Arctic climate system and general trends from 1979 to 2013 compared with the observations, but it shows limited skills in modeling local trends and interannual variability.展开更多
By means of monthly mean NCEP/NCAR data analyses, this note investigates the lag influences of winter circulation conditions in the tropical western Pacific on South Asian summer monsoon through the methods of composi...By means of monthly mean NCEP/NCAR data analyses, this note investigates the lag influences of winter circulation conditions in the tropical western Pacific on South Asian summer monsoon through the methods of composite, correlation and statistical confident test. The results indicate clearly that winter climate variations in the equatorial western Pacific would produce significant influences on the following South Asian summer monsoon, and with the lapse of time the lag influences show clearly moving northward and extending westward features. When winter positive (negative) sea level pressure anomalies occupy the equatorial western Pacific, there is an anticyclonic (cyclonic) circulation anomaly appearing in the northwestern Pacific. With the lapse of time, the anticyclonic (cyclonic) circulation anomaly gradually moves to northeast, and its axis in the west-east directions also stretches, therefore, easterly (westerly) anomalies in the south part of the anticyclonic (cyclonic) circulation anomaly展开更多
The variations of surface air temperature(SAT)over the Arctic are closely related to global climate change.Based on reanalysis datasets and a newly defined Aleutian Low intensity index,we found a good correlation betw...The variations of surface air temperature(SAT)over the Arctic are closely related to global climate change.Based on reanalysis datasets and a newly defined Aleutian Low intensity index,we found a good correlation between intensity of winter Aleutian Low and the SAT over the Arctic during the subsequent summer.Explanations were given using correlation analysis,composite analysis,and singular value decomposition methods.When intensity of winter Aleutian Low was weaker,sea surface temperature appeared higher in the North Pacific in the subsequent spring and summer,resulting in mean meridional circulation anomalies and 500 hPa geopotential height anomalies in spring and summer.Anomalous upward motion in mid-latitudes and downward motion in high latitudes(Ferrel cell weakening)transported the warmer air to the north from lower layer to the upper layer followed by increases in the SAT over the Arctic.Anomalous downward motion over about 75°N also caused consequent adiabatic warming and contributed to inhibit the heat transportation from surface to upper layer.Negative 500 hPa geopotential height anomalies existed in mid-latitudes and positive anomalies existed in high latitudes.The pattern(low-in-south and high-in-north)benefited from increasing the inflow volume flux of the Bering Strait,which also made the SAT over the Arctic increase.The results of this study reveal the process that the summer SAT over the Arctic was modulated by interannual variability of intensity of winter Aleutian Low.展开更多
文摘In November 1984,China launched its first expedition to the Southern Ocean and the Antarctic continent,culminating in the establishment of its first year-round research station—Great Wall Station—on the Antarctic Peninsula in February 1985.Forty years later,in February 2024,China’s fifth research station,Qinling Station,commenced operations on Inexpress-ible Island near Terra Nova Bay.
基金supported by the National Key Research and Development Program of China(2018YFA 0605703)the National Natural Science Foundation of China(No.41976193 and No.42176243)+8 种基金X.CHEN was supported by the National Key Research and Development Program of China(2019YFC1509100)the National Science Foundation of China(No.41825012)B.WU was supported by the Major Program of the National Natural Science Foundation of China(41790472)the National Key Basic Research Project of China(2019YFA0607002)the National Natural Science Foundation of China(41730959)X.CHENG was funded by the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(Grant No.311021008)M.DING was supported by the National Natural Science Foundation of China(42122047 and 42105036)the Basic Research Fund of the Chinese Academy of Meteorological Sciences(2021Y021 and 2021Z006)Q.SUN was supported by the National Key R&D Program of China(No.2022YFE0106300).
文摘During the recent four decades since 1980,a series of modern climate satellites were launched,allowing for the measurement and record-keeping of multiple climate parameters,especially over the polar regions where traditional observations are difficult to obtain.China has been actively engaging in polar expeditions.Many observations were conducted during this period,accompanied by improved Earth climate models,leading to a series of insightful understandings concerning Arctic and Antarctic climate changes.Here,we review the recent progress China has made concerning Arctic and Antarctic climate change research over the past decade.The Arctic temperature increase is much higher than the global-mean warming rate,associated with a rapid decline in sea ice,a phenomenon called the Arctic Amplification.The Antarctic climate changes showed a zonally asymmetric pattern over the past four decades,with most of the fastest changes occurring over West Antarctica and the Antarctic Peninsula.The Arctic and Antarctic climate changes were driven by anthropogenic greenhouse gas emissions and ozone loss,while tropical-polar teleconnections play important roles in driving the regional climate changes and extreme events over the polar regions.Polar climate changes may also feedback to the entire Earth climate system.The adjustment of the circulation in both the troposphere and the stratosphere contributed to the interactions between the polar climate changes and lower latitudes.Climate change has also driven rapid Arctic and Southern ocean acidification.Chinese researchers have made a series of advances in understanding these processes,as reviewed in this paper.
文摘Long-term survival of 116 leukemia/MDS patients received allo-SCT conditioned by a regimen with ATG-F or without ATG-F was analysed, together with the impact of ATG-F on the long-term survival, GVHD and disease relapse. Seventy patients received an ATG-F containing conditioning regimen FBCA, and 46 patients received a non-ATG-F FBC regimen. The FBCA regimen was associated with a 5-year survival of 65.4% in the complete HLA-matched group and 39.3% in the HLA-mismatched group. The difference between the two groups was significant (P = 0.012). For the FBC conditioning regimen, the 5-year overall survival of HLA-matched patients and the HLA-mismatched patients was 34.2% and 24.2% respectively (P = 0.216). The incidence of cGVHD was 32.9% and 83.6% in the FBCA and FBC condition regimen group respectively. Only 2.9% of the cases showed extensive cGVHD in the FBCA group while it was 69.4% in the FBC group (P = 0.00). Multivariate analysis indicated that relapse was related to the disease status and HLA typing, but unrelated to the conditioning regimens whether or not ATG-F was used (HR 0.54, P = 0.109). We conclude that the addition of ATG-F to conditioning regimen favours the longterm survival of allo-SCT.
基金Supported by the National Natural Science Foundation of China(42375023 and 41730959).
文摘This paper provides a brief summary of the representative research outcomes on the Arctic-midlatitude connection since the founding of the Chinese Meteorological Society in 1924.(1)The revelation of the North Atlantic Oscillation,the Arctic Oscillation,and the Arctic Dipole anomaly represents three significant milestones in the study of large-scale Arctic-midlatitude teleconnections.(2)Before the mid-1990s,Chinese researchers revealed the key pathways by which Arctic cold air affects cold wave processes in East Asia,the key areas for cold waves,and the dynamical processes of cold high pressure during cold waves.These findings are prominent representatives of Arctic-midlatitude connection research and have profoundly influenced the development of meteorology in China and the prediction of cold wave processes in winter.(3)The melting of Arctic sea ice and Arctic warming anomalies influence midlatitude weather events and climate variations by affecting the evaporation of water vapor from the ocean surface,turbulent heat flux between atmosphere and ocean,meridional temperature gradient of the atmosphere,zonal winds,the location and intensity of the storm track,and propagation of large-scale horizontal teleconnection patterns and planetary waves between the troposphere and stratosphere.(4)The melting of Arctic sea ice plays important roles in modulating interdecadal variations of the winter atmospheric circulation,leading to alternative occurrence of a warm Arctic-cold Eurasia(2004/05-2012/13)and a warm Arctic-warm Eurasia(2013/14-2018/19).The former strengthens the connection between the Arctic and midlatitudes,while the latter corresponds to a noticeable weakening of the Arctic-midlatitude connection.(5)The melting of Arctic sea ice facilitates the frequent occurrence of Arctic cold anomalies in the middle and lower troposphere during summer,leading to the formation of blocking circulation anomalies in high-latitude regions that are conducive to the occurrence of heatwaves and wildfires in some regions of high-latitudes.(6)The frequency of summer heatwaves averaged from the Qinghai-Xizang Plateau to the mid and low latitude areas of eastern China has a direct dynamical link with the frequent occurrence of summer Arctic cold anomalies in the middle and lower troposphere.The systematic northward shift of the tropospheric zonal winds over East Asia is the intrinsic mechanism that connects the Arctic cold anomalies with the heatwaves in East Asia.Future research on Arctic-midlatitude connection should pay more attention to the role of Arctic sea ice melting in the low-frequency variability of atmospheric circulation,particularly emphasizing the impacts of both different spatial anomalies and anomalous amplitudes in Arctic sea ice concentrations.It is necessary to quantitatively examine the role of Arctic sea ice melting in extreme weather and climate events.
基金the National Natural Science Foundation of China (Grant No. 49905003).
文摘Variations of winter Arctic sea ice bordering on the North Atlantic are closely related to climate variations in the same region. When winter North Atlantic Oscillation (NAO) index is positive (negative) anomaly phase, Icelandic Low is obviously deepened and shifts northwards (southwards). Simultaneously, the Subtropical High over the North Atlantic is also intensified, and moves northwards (southwards). Those anomalies strengthen (weaken) westerly between Icelandic Low and the Subtropical High, and further result in positive (negative) sea surface temperature (SST) anomalies in the mid-latitude of the North Atlantic, and increase (decrease) the warm water transportation from the mid-latitude to the Barents Sea, which causes positive (negative) mixed-layer water temperature anomalies in the south part of the Barents Sea. Moreover, the distribution of anomaly air temperature clearly demonstrates warming (cooling) in northern Europe and the subarctic regions (including the Barents Sea) and cooling
基金Supported by the National Key Research and Development Program of China(2016YFA0602704)National Natural Science Foundation of China(41505068)
文摘The Chinese Academy of Meteorological Sciences Climate System Model(CAMS-CSM) is a newly developed global climate model that will participate in the Coupled Model Intercomparison Project phase 6. Based on historical simulations(1900-2013), we evaluate the model performance in simulating the observed characteristics of the Arctic climate system, which includes air temperature, precipitation, the Arctic Oscillation(AO), ocean temperature/salinity,the Atlantic meridional overturning circulation(AMOC), snow cover, and sea ice. The model-data comparisons indicate that the CAMS-CSM reproduces spatial patterns of climatological mean air temperature over the Arctic(60°-90°N) and a rapid warming trend from 1979 to 2013. However, the warming trend is overestimated south of the Arctic Circle, implying a subdued Arctic amplification. The distribution of climatological precipitation in the Arctic is broadly captured in the model, whereas it shows limited skills in depicting the overall increasing trend. The AO can be reproduced by the CAMS-CSM in terms of reasonable patterns and variability. Regarding the ocean simulation, the model underestimates the AMOC and zonally averaged ocean temperatures and salinity above a depth of 500 m, and it fails to reproduce the observed increasing trend in the upper ocean heat content in the Arctic. The largescale distribution of the snow cover extent(SCE) in the Northern Hemisphere and the overall decreasing trend in the spring SCE are captured by the CAMS-CSM, while the biased magnitudes exist. Due to the underestimation of the AMOC and the poor quantification of air–sea interaction, the CAMS-CSM overestimates regional sea ice and underestimates the observed decreasing trend in Arctic sea–ice area in September. Overall, the CAMS-CSM reproduces a climatological distribution of the Arctic climate system and general trends from 1979 to 2013 compared with the observations, but it shows limited skills in modeling local trends and interannual variability.
基金This work was supported by the National Key Basic Research Program (Grant No. G1998040900).
文摘By means of monthly mean NCEP/NCAR data analyses, this note investigates the lag influences of winter circulation conditions in the tropical western Pacific on South Asian summer monsoon through the methods of composite, correlation and statistical confident test. The results indicate clearly that winter climate variations in the equatorial western Pacific would produce significant influences on the following South Asian summer monsoon, and with the lapse of time the lag influences show clearly moving northward and extending westward features. When winter positive (negative) sea level pressure anomalies occupy the equatorial western Pacific, there is an anticyclonic (cyclonic) circulation anomaly appearing in the northwestern Pacific. With the lapse of time, the anticyclonic (cyclonic) circulation anomaly gradually moves to northeast, and its axis in the west-east directions also stretches, therefore, easterly (westerly) anomalies in the south part of the anticyclonic (cyclonic) circulation anomaly
基金supported by the National Natural Science Foundation of China(40976014,41076011,41106024 and 41106159)
文摘The variations of surface air temperature(SAT)over the Arctic are closely related to global climate change.Based on reanalysis datasets and a newly defined Aleutian Low intensity index,we found a good correlation between intensity of winter Aleutian Low and the SAT over the Arctic during the subsequent summer.Explanations were given using correlation analysis,composite analysis,and singular value decomposition methods.When intensity of winter Aleutian Low was weaker,sea surface temperature appeared higher in the North Pacific in the subsequent spring and summer,resulting in mean meridional circulation anomalies and 500 hPa geopotential height anomalies in spring and summer.Anomalous upward motion in mid-latitudes and downward motion in high latitudes(Ferrel cell weakening)transported the warmer air to the north from lower layer to the upper layer followed by increases in the SAT over the Arctic.Anomalous downward motion over about 75°N also caused consequent adiabatic warming and contributed to inhibit the heat transportation from surface to upper layer.Negative 500 hPa geopotential height anomalies existed in mid-latitudes and positive anomalies existed in high latitudes.The pattern(low-in-south and high-in-north)benefited from increasing the inflow volume flux of the Bering Strait,which also made the SAT over the Arctic increase.The results of this study reveal the process that the summer SAT over the Arctic was modulated by interannual variability of intensity of winter Aleutian Low.
