Based on the skewed function,the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are inve...Based on the skewed function,the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are investigated,where the climate states are referred to as State I,State II and State III,i.e.,the daily minimum temperature records of 1961-1990,1971-2000,and 1981-2009.The results show that in space the frequency of high temperature events in summer decreases clearly in the lower and middle reaches of the Yellow River in State I and that low temperature events decrease in northern China in State II.In the present state,the frequency of high temperature events increases significantly in most areas over China except the north east,while the frequency of low temperature events decreases mainly in north China and the regions between the Yangtze River and the Yellow River.The distributions of frequencies and strengths of extreme temperature events are consistent in space.The analysis of time evolution of extreme events shows that the occurrence of high temperature events become higher with the change in state,while that of low temperature events decreases.High temperature events are becoming stronger as well and deserve to be paid special attention.展开更多
Based on daily observation data of the Three Gorges Region(TGR)of the Yangtze River basin and global reanalysis data,the climate characteristics,climate events,and meteorological disasters of the TGR in 2022 and 2023 ...Based on daily observation data of the Three Gorges Region(TGR)of the Yangtze River basin and global reanalysis data,the climate characteristics,climate events,and meteorological disasters of the TGR in 2022 and 2023 were analyzed.For the TGR,the average annual temperature for 2022 and 2023 was 0.8℃ and 0.4℃ higher than normal,respectively,making them the two warmest years in the past decade.In 2022,the TGR experienced its warmest summer on record.The average air temperature was 2.4℃ higher than the average,and there were 24.8 days of above-average high temperature days during summer.Rainfall in the TGR varied significantly between 2022 and 2023.Annual rainfall was 18.4%below normal and drier than normal in most parts of the region.In contrast,the precipitation in 2023 was considerably higher than the long-term average,and above normal for almost the entire year.The average wind speed exhibited minimal variation between the two years.However,the number of foggy days and relative humidity increased in 2023 compared to 2022.In 2022–2023,the TGR mainly experienced meteorological disasters such as extreme high temperatures,regional heavy rain and flooding,overcast rain,and inverted spring chill.Analysis indicates that the abnormal western Pacific subtropical high and the abnormal persistence of the eastward-shifted South Asian high were the two important drivers of the durative enhancement of record-breaking high temperature in the summer of 2022.展开更多
The results of four versions of IAP/LASG Global Ocean-Atmosphere-Land System Model (GOALS) are analyzed separately over the oceans and over continents, and compared with observed data. Some fundamental atmospheric var...The results of four versions of IAP/LASG Global Ocean-Atmosphere-Land System Model (GOALS) are analyzed separately over the oceans and over continents, and compared with observed data. Some fundamental atmospheric variables including surface air temperature (SAT), sea level pressure (SLP) and precipitation are examined to evaluate the ability of the GOALS model to simulate the contemporary climate and climate variability. In general, all four versions of the GOALS model are capable of reproducing the main features of the mean state and seasonal variation of the observed climate with reasonable accuracy. The evaluation also reveals some weakness of the model. According to this study, we can clearly see that the essential discrepancy of global averaged SLP lies over the continents in boreal summer. The simulated higher SAT over land versus the observed is mainly due to the effect of the land surface process. It is worth noting the underestimation by simulated precipitation rates mostly appears over the oceans, yet over-land precipitation is higher in high and middle latitudes than the observed for the boreal winter. Through intercomparisons among different versions of the model, it can be clearly seen that the incorporation of the diurnal cycle of solar radiation apparently improves the simulation of SAT, especially in the low and middle latitudes over land. Also, the introduction of the diurnal cycle shows a great improvement in precipitation in tropical continents and wintertime precipitation in high and middle latitudes. Furthermore, based on the daily flux anomaly exchange scheme (DFA), the latest version of GOALS model simulated over-ocean temperature variability is improved in the low and middle latitudes. Having compared the standard deviation of the annual mean surface air temperature (SAT) simulated by the GOALS model to observation, it is found that all four versions of the GOALS model underestimate surface air temperature variability over both oceans and land relative to observations. Several factors that may contribute to these differences between simulated and observed temperature variability are identified.展开更多
The Three Gorges Region(TGR)of the Yangtze River basin exhibited warm and dry climatic characteristics in 2024.The annual mean temperature in the TGR was 18.6℃,which was 1.2℃above normal and marked the highest level...The Three Gorges Region(TGR)of the Yangtze River basin exhibited warm and dry climatic characteristics in 2024.The annual mean temperature in the TGR was 18.6℃,which was 1.2℃above normal and marked the highest level since 1961.All four seasons were warmer than normal,with spring and autumn both recording their highest temperatures since 1961.Additionally,the TGR recorded 57.2 high-temperature days in 2024,reaching a historic high since 1961 and exceeding the previous record set in 2022 by 2.4 days.Annual rainfall was 11.2%below normal,with spring,summer,and autumn all being drier than normal.However,the number of heavy rain days was slightly higher than normal.The annual mean wind speed in the TGR ranked as the second-highest since 1961,only slightly lower than in 2022.The annual mean relative humidity was below normal and the number of fog days across large areas of the TGR decreased compared to 2023.In 2024,the TGR experienced extreme high-temperature events characterized by exceptional intensity and prolonged duration,accompanied by generally severe meteorological drought conditions.During the year,the TGR also experienced frequent and intense cooling events,an early onset of heavy rainfall(including severe convective weather),and exceptionally extreme rainstorm events.展开更多
We examine possible funding sources for constructing Climate Change Haven Communities on a global basis. Areas of the planet that have the potential to house persons migrating to “safe havens” in their own or other ...We examine possible funding sources for constructing Climate Change Haven Communities on a global basis. Areas of the planet that have the potential to house persons migrating to “safe havens” in their own or other countries will require the rapid construction of communities capable of supporting them, their families, businesses and farms. However, different political-economic conditions are found across the areas which can serve as locations for these Climate Change Haven Communities. We develop funding and construction strategies for the United States (free-market capitalism), France and Spain (European Union supported economies), and Taiwan region (state-directed economy). The proposals for the Taiwan region should also be applicable to the rest of China.展开更多
This report is a summary of China’s climate,as well as major weather and climate events,during 2021.In 2021,the mean temperature in China was 10.5°C,which was 1.0°C above normal(1981–2010 average)and broke...This report is a summary of China’s climate,as well as major weather and climate events,during 2021.In 2021,the mean temperature in China was 10.5°C,which was 1.0°C above normal(1981–2010 average)and broke the highest record since 1951.The annual rainfall in China was 672.1 mm,which was 6.7%above normal.Also,the annual rainfall in northern China was 40.2%above normal,which ranked second highest since 1961.The rainstorm intensity in the rainy season was strong and featured significant extremes,and disasters caused by rainstorms and flooding were more serious than the average in the past decade.In particular,the extremely strong rainstorm in Henan during July and autumn caused flooding in the middle and lower reaches of the Yellow River with severe consequences.Heatwaves occurred more frequently than normal,and their durations in southern China were longer than normal in summer and autumn.Phased drought was obvious,and caused serious impacts in South China.The number of generated and landfalling typhoons was lower than normal;however,Typhoon In-fa broke the record for the longest overland duration,held since 1949,and affected a wide area.Severe convective weather and extreme windy weather occurred frequently,causing serious impacts.The number of cold waves was more than normal,which caused wide-ranging extremely low temperatures in many places.Sandstorms appeared earlier than normal in 2021,and the number of strong dust storm processes was more than normal.展开更多
In 2020,the average air temperature in the Three Gorges Region(TGR)of the Yangtze River basin was 17.2℃,which was close to normal,there were exceptionally fewer days than normal with high temperatures,and the high-te...In 2020,the average air temperature in the Three Gorges Region(TGR)of the Yangtze River basin was 17.2℃,which was close to normal,there were exceptionally fewer days than normal with high temperatures,and the high-temperature events mainly occurred in August.Meanwhile,the average precipitation was 1530.8 mm,which was a remarkable 29%more than usual,and the second-highest since 1961.The precipitation was obviously above-normal in summer,and the precipitation in both June and July was the second-highest of the same period in history.The average number of rainstorm days was higher than normal,and the second-highest since 1961.The average wind speed in the TGR was apparently higher than normal;the average relative humidity was slightly higher than normal;and there were no instances of acid rain,with the rain acidity showing a significant weakening trend over the previous 15 years.In the summer of 2020,the TGR experienced heavy rainstorms and flood disasters.Analysis shows that the frequent southward movement of cold air and abundant warm water vapor from the southwest were the direct causes of the abnormally high precipitation in the TGR from June to July.After the spring of 2020,the continuously high sea surface temperature in the Indian Ocean led to a continuously strong western Pacific subtropical high and its average location being situated more to the south than normal,which might have been an important cause for the abnormal climate conditions in the Yangtze River basin from June to July.展开更多
This report is a summary of China’s climate,as well as major weather and climate events,during 2020.In 2020,the mean air temperature in China was 10.25℃,which was 0.7℃ above normal(1981–2010 average),and the annua...This report is a summary of China’s climate,as well as major weather and climate events,during 2020.In 2020,the mean air temperature in China was 10.25℃,which was 0.7℃ above normal(1981–2010 average),and the annual rainfall was 694.8 mm,which was 10.3%above normal.In general,disasters caused by rainstorms and flooding were more serious than those by drought.In summer,southern China experienced the most severe flooding with extreme heavy rainstorms since 1998.Drought brought slight impacts and losses in China.The seasonal transition from spring to summer was earlier than normal.High temperatures occurred earlier than normal with extreme values,and lasted longer than normal in summer over the south of China.The number of landfalling typhoons was lower than normal.Cold-air processes had a wide influence and brought a substantial decrease in air temperature in local areas.Compared with the average values of the past 10 years,the affected crop area and the numbers of deaths and missing persons in 2020 were significantly smaller,while direct economic losses were slightly larger.展开更多
In 2018,the mean temperature in China was 0.54℃above normal,and the annual rainfall was 7%above normal.More typhoons made landfall with severe damage.Low-temperature freezing and snow disasters occurred frequently wi...In 2018,the mean temperature in China was 0.54℃above normal,and the annual rainfall was 7%above normal.More typhoons made landfall with severe damage.Low-temperature freezing and snow disasters occurred frequently with extensive losses.In summer,rainstorms occurred frequently with relatively limited damage.Northeast China and Central East China suffered extreme heatwaves.Regional and periodic droughts resulted in slight impacts.Severe convective weather and dust storms were relatively less,but periodic haze influenced air quality and human health.The areas of affected crops,death tolls,direct economic losses were all significantly less than those over the last 5 years.展开更多
This report is a summary of China’s climate,as well as major weather and climate events,during 2019.In 2019,the mean temperature in China was 10.34°C,which was 0.79°C above normal(1981–2010 average),and th...This report is a summary of China’s climate,as well as major weather and climate events,during 2019.In 2019,the mean temperature in China was 10.34°C,which was 0.79°C above normal(1981–2010 average),and the annual rainfall was 645.5 mm,which was 2.5%above normal.There was increased typhoon genesis but decreased and weaker landfalls.Rainstorms occurred frequently with relatively limited damage.The number of high-temperature days was more than normal,with significant regional features.Obvious regional and periodic droughts resulted in slight impacts and losses.Severe convective weather events were relatively less and brought about limited economic losses.Low-temperature freezing and snow disasters were obviously light.Northern China experienced fewer dust storms in spring.Finally,the areas of affected crops,the numbers of deaths and missing people,and direct economic losses were all significantly less than average over the past 10 years.展开更多
How many NGOs were there in the climate change field in the United States？ Who were they？ And what was the relationship between them？ In the United States,climate change was only a branch of environmental issues at...How many NGOs were there in the climate change field in the United States？ Who were they？ And what was the relationship between them？ In the United States,climate change was only a branch of environmental issues at the beginning; therefore there were no specific quantitative statistics and network analysis of NGOs in climate change. Diversity was an important feature of NGOs in American climate change fields,and it showed a complex organizational ecology through varieties of networks and interaction among organizations. In order to make a difference in climate field,Chinese NGOs firstly needed to improve and enhance their own abilities.展开更多
Based on the analysis of Levitus data, the climatic states of the warm pool in the Indian Ocean (WPIO) and in the Pacific Ocean (WPPO) are studied. It is found that WPIO has a relatively smaller area, a shallower bott...Based on the analysis of Levitus data, the climatic states of the warm pool in the Indian Ocean (WPIO) and in the Pacific Ocean (WPPO) are studied. It is found that WPIO has a relatively smaller area, a shallower bottom and a slightly lower seawater temperature than those of WPPO. The horizontal area at different depths, volumes, central positions, and bottom depths of both WPIO and WPPO show quite apparent signals of seasonal variation. The maximum amplitude of WPIO surface area’s seasonal variation is 58% larger over the annual mean value. WPIO’s maximum volume variation amplitude is 66% larger over the annual mean value. The maximum variation amplitudes of the surface area and volume of WPPO are 20. 9% and 20.6% larger over the annual mean value respectively. WPIO and WPPO show different temporal and spatial characteristics mainly due to the different wind fields and restriction of ocean basin geometry. For instance, seasonal northern displacement of WPIO is, to some extent, constrained by the basin of the Indian Ocean, while WPPO moves relatively freely in the longitudinal direction. The influence of WPIO and WPPO over the atmospheric motion must be quite different.展开更多
By use of 1948-2007 NCEP/NCAR reanalysis monthly geopotential data, a set of circulation indices are defined to characterize the polar vortex at 10 hPa in the Southern Hemisphere, including area-（S）, intensity-（P）...By use of 1948-2007 NCEP/NCAR reanalysis monthly geopotential data, a set of circulation indices are defined to characterize the polar vortex at 10 hPa in the Southern Hemisphere, including area-（S）, intensity-（P） and centre position-（λc , φc） indices. Sea-sonal variation, interannual anomalies and their possible causes of 10 hPa polar vortex in the Southern Hemisphere are analyzed by using these indices, the relationship between 10 hPa polar vortex strength and the Antarctic Oscillation are analyzed as well. The results show that： （1） the polar region at 10 hPa in the Southern Hemisphere is controlled by anticyclone （cyclone） from Dec. to Jan. （from Mar. to Oct.）, Feb. and Nov. are circulation transition seasons. （2） Intensity index （P） and area index （S） of anticy-clone （cyclone） in Jan. （Jul.） show a significant spike in the late 1970s, the anticyclone （cyclone） enhances （weakens） from ex-tremely weak （strong） oscillation to near the climatic mean before a spike, anticyclone tends to the mean state from very strong oscillation and cyclone oscillates in the weaker state after the spike. （3） There is significant interdecadal change for the anticyclone center in Jan., while markedly interannual variation for cyclone center in July. （4） The ozone anomalies can cause the interannual anomaly of the polar anticyclone at 10 hPa in the Southern Hemisphere in Jan. （positive correlation between them）, but it is not related to the polar cyclone anomalies. （5） There is notable negative correlation between the polar vortex intensity index P and the Antarctic Oscillation index （AAOI）, thus AAOI can be represented by P.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 41105033)the National Basic Research Program of China (Grant No. 2012CB955901)
文摘Based on the skewed function,the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are investigated,where the climate states are referred to as State I,State II and State III,i.e.,the daily minimum temperature records of 1961-1990,1971-2000,and 1981-2009.The results show that in space the frequency of high temperature events in summer decreases clearly in the lower and middle reaches of the Yellow River in State I and that low temperature events decrease in northern China in State II.In the present state,the frequency of high temperature events increases significantly in most areas over China except the north east,while the frequency of low temperature events decreases mainly in north China and the regions between the Yangtze River and the Yellow River.The distributions of frequencies and strengths of extreme temperature events are consistent in space.The analysis of time evolution of extreme events shows that the occurrence of high temperature events become higher with the change in state,while that of low temperature events decreases.High temperature events are becoming stronger as well and deserve to be paid special attention.
基金supported by the National Key Research and Development Program of China[grant number 2023YFC3206001]the Three Gorges Project Comprehensive Monitoring Program for Operational Safety[grant number SK2023019]which funded by the Ministry of Water Resources of China.
文摘Based on daily observation data of the Three Gorges Region(TGR)of the Yangtze River basin and global reanalysis data,the climate characteristics,climate events,and meteorological disasters of the TGR in 2022 and 2023 were analyzed.For the TGR,the average annual temperature for 2022 and 2023 was 0.8℃ and 0.4℃ higher than normal,respectively,making them the two warmest years in the past decade.In 2022,the TGR experienced its warmest summer on record.The average air temperature was 2.4℃ higher than the average,and there were 24.8 days of above-average high temperature days during summer.Rainfall in the TGR varied significantly between 2022 and 2023.Annual rainfall was 18.4%below normal and drier than normal in most parts of the region.In contrast,the precipitation in 2023 was considerably higher than the long-term average,and above normal for almost the entire year.The average wind speed exhibited minimal variation between the two years.However,the number of foggy days and relative humidity increased in 2023 compared to 2022.In 2022–2023,the TGR mainly experienced meteorological disasters such as extreme high temperatures,regional heavy rain and flooding,overcast rain,and inverted spring chill.Analysis indicates that the abnormal western Pacific subtropical high and the abnormal persistence of the eastward-shifted South Asian high were the two important drivers of the durative enhancement of record-breaking high temperature in the summer of 2022.
基金This study was supported by the National Natural Science Foundation of China under Grant No. 49875012.
文摘The results of four versions of IAP/LASG Global Ocean-Atmosphere-Land System Model (GOALS) are analyzed separately over the oceans and over continents, and compared with observed data. Some fundamental atmospheric variables including surface air temperature (SAT), sea level pressure (SLP) and precipitation are examined to evaluate the ability of the GOALS model to simulate the contemporary climate and climate variability. In general, all four versions of the GOALS model are capable of reproducing the main features of the mean state and seasonal variation of the observed climate with reasonable accuracy. The evaluation also reveals some weakness of the model. According to this study, we can clearly see that the essential discrepancy of global averaged SLP lies over the continents in boreal summer. The simulated higher SAT over land versus the observed is mainly due to the effect of the land surface process. It is worth noting the underestimation by simulated precipitation rates mostly appears over the oceans, yet over-land precipitation is higher in high and middle latitudes than the observed for the boreal winter. Through intercomparisons among different versions of the model, it can be clearly seen that the incorporation of the diurnal cycle of solar radiation apparently improves the simulation of SAT, especially in the low and middle latitudes over land. Also, the introduction of the diurnal cycle shows a great improvement in precipitation in tropical continents and wintertime precipitation in high and middle latitudes. Furthermore, based on the daily flux anomaly exchange scheme (DFA), the latest version of GOALS model simulated over-ocean temperature variability is improved in the low and middle latitudes. Having compared the standard deviation of the annual mean surface air temperature (SAT) simulated by the GOALS model to observation, it is found that all four versions of the GOALS model underestimate surface air temperature variability over both oceans and land relative to observations. Several factors that may contribute to these differences between simulated and observed temperature variability are identified.
基金supported by the Innovation and Development Special Project of the China Meteorological Administration[grant number CXFZ2024J071]the National Key Research and Development Program of China[grant number 2023YFC3206001].
文摘The Three Gorges Region(TGR)of the Yangtze River basin exhibited warm and dry climatic characteristics in 2024.The annual mean temperature in the TGR was 18.6℃,which was 1.2℃above normal and marked the highest level since 1961.All four seasons were warmer than normal,with spring and autumn both recording their highest temperatures since 1961.Additionally,the TGR recorded 57.2 high-temperature days in 2024,reaching a historic high since 1961 and exceeding the previous record set in 2022 by 2.4 days.Annual rainfall was 11.2%below normal,with spring,summer,and autumn all being drier than normal.However,the number of heavy rain days was slightly higher than normal.The annual mean wind speed in the TGR ranked as the second-highest since 1961,only slightly lower than in 2022.The annual mean relative humidity was below normal and the number of fog days across large areas of the TGR decreased compared to 2023.In 2024,the TGR experienced extreme high-temperature events characterized by exceptional intensity and prolonged duration,accompanied by generally severe meteorological drought conditions.During the year,the TGR also experienced frequent and intense cooling events,an early onset of heavy rainfall(including severe convective weather),and exceptionally extreme rainstorm events.
文摘We examine possible funding sources for constructing Climate Change Haven Communities on a global basis. Areas of the planet that have the potential to house persons migrating to “safe havens” in their own or other countries will require the rapid construction of communities capable of supporting them, their families, businesses and farms. However, different political-economic conditions are found across the areas which can serve as locations for these Climate Change Haven Communities. We develop funding and construction strategies for the United States (free-market capitalism), France and Spain (European Union supported economies), and Taiwan region (state-directed economy). The proposals for the Taiwan region should also be applicable to the rest of China.
基金This work was jointly supported by the National Natural Science Foundation of China[grant number 41875120]a National Key Research and Development Project[grant number 2017YFC1502402].
文摘This report is a summary of China’s climate,as well as major weather and climate events,during 2021.In 2021,the mean temperature in China was 10.5°C,which was 1.0°C above normal(1981–2010 average)and broke the highest record since 1951.The annual rainfall in China was 672.1 mm,which was 6.7%above normal.Also,the annual rainfall in northern China was 40.2%above normal,which ranked second highest since 1961.The rainstorm intensity in the rainy season was strong and featured significant extremes,and disasters caused by rainstorms and flooding were more serious than the average in the past decade.In particular,the extremely strong rainstorm in Henan during July and autumn caused flooding in the middle and lower reaches of the Yellow River with severe consequences.Heatwaves occurred more frequently than normal,and their durations in southern China were longer than normal in summer and autumn.Phased drought was obvious,and caused serious impacts in South China.The number of generated and landfalling typhoons was lower than normal;however,Typhoon In-fa broke the record for the longest overland duration,held since 1949,and affected a wide area.Severe convective weather and extreme windy weather occurred frequently,causing serious impacts.The number of cold waves was more than normal,which caused wide-ranging extremely low temperatures in many places.Sandstorms appeared earlier than normal in 2021,and the number of strong dust storm processes was more than normal.
基金supported by the National Key R&D Program of China[grant numbers 2017YFD0300201,2017YFA0605004,and 2017YFC1502402]funds of comprehensive monitoring of the Three Gorges Project,which was financed by the Ministry of Water Resources of China。
文摘In 2020,the average air temperature in the Three Gorges Region(TGR)of the Yangtze River basin was 17.2℃,which was close to normal,there were exceptionally fewer days than normal with high temperatures,and the high-temperature events mainly occurred in August.Meanwhile,the average precipitation was 1530.8 mm,which was a remarkable 29%more than usual,and the second-highest since 1961.The precipitation was obviously above-normal in summer,and the precipitation in both June and July was the second-highest of the same period in history.The average number of rainstorm days was higher than normal,and the second-highest since 1961.The average wind speed in the TGR was apparently higher than normal;the average relative humidity was slightly higher than normal;and there were no instances of acid rain,with the rain acidity showing a significant weakening trend over the previous 15 years.In the summer of 2020,the TGR experienced heavy rainstorms and flood disasters.Analysis shows that the frequent southward movement of cold air and abundant warm water vapor from the southwest were the direct causes of the abnormally high precipitation in the TGR from June to July.After the spring of 2020,the continuously high sea surface temperature in the Indian Ocean led to a continuously strong western Pacific subtropical high and its average location being situated more to the south than normal,which might have been an important cause for the abnormal climate conditions in the Yangtze River basin from June to July.
基金This work was jointly supported by the National Natural Science Foundation of China[grant numbers 41875120 and 41605069]the National Key Research and Development Project[grant number 2017YFC1502402].
文摘This report is a summary of China’s climate,as well as major weather and climate events,during 2020.In 2020,the mean air temperature in China was 10.25℃,which was 0.7℃ above normal(1981–2010 average),and the annual rainfall was 694.8 mm,which was 10.3%above normal.In general,disasters caused by rainstorms and flooding were more serious than those by drought.In summer,southern China experienced the most severe flooding with extreme heavy rainstorms since 1998.Drought brought slight impacts and losses in China.The seasonal transition from spring to summer was earlier than normal.High temperatures occurred earlier than normal with extreme values,and lasted longer than normal in summer over the south of China.The number of landfalling typhoons was lower than normal.Cold-air processes had a wide influence and brought a substantial decrease in air temperature in local areas.Compared with the average values of the past 10 years,the affected crop area and the numbers of deaths and missing persons in 2020 were significantly smaller,while direct economic losses were slightly larger.
基金jointly supported by the National Science and Technology Fundamental Resources Investigation Project[grant number 2017FY101201]the National Key R&D Program of China [grant number 2016YFE0102400,2017-YFD0300201,and 2017YFA0605004]
文摘In 2018,the mean temperature in China was 0.54℃above normal,and the annual rainfall was 7%above normal.More typhoons made landfall with severe damage.Low-temperature freezing and snow disasters occurred frequently with extensive losses.In summer,rainstorms occurred frequently with relatively limited damage.Northeast China and Central East China suffered extreme heatwaves.Regional and periodic droughts resulted in slight impacts.Severe convective weather and dust storms were relatively less,but periodic haze influenced air quality and human health.The areas of affected crops,death tolls,direct economic losses were all significantly less than those over the last 5 years.
基金This work was jointly supported by the National Key R&D Program of China[grant number 2018YFE0196000]the National Science and Technology Fundamental Resources Investigation Project[grant number 2017FY101201].
文摘This report is a summary of China’s climate,as well as major weather and climate events,during 2019.In 2019,the mean temperature in China was 10.34°C,which was 0.79°C above normal(1981–2010 average),and the annual rainfall was 645.5 mm,which was 2.5%above normal.There was increased typhoon genesis but decreased and weaker landfalls.Rainstorms occurred frequently with relatively limited damage.The number of high-temperature days was more than normal,with significant regional features.Obvious regional and periodic droughts resulted in slight impacts and losses.Severe convective weather events were relatively less and brought about limited economic losses.Low-temperature freezing and snow disasters were obviously light.Northern China experienced fewer dust storms in spring.Finally,the areas of affected crops,the numbers of deaths and missing people,and direct economic losses were all significantly less than average over the past 10 years.
基金Supported by the Fundamental Research Funds for the Central Universities(SKZZX2013054)
文摘How many NGOs were there in the climate change field in the United States？ Who were they？ And what was the relationship between them？ In the United States,climate change was only a branch of environmental issues at the beginning; therefore there were no specific quantitative statistics and network analysis of NGOs in climate change. Diversity was an important feature of NGOs in American climate change fields,and it showed a complex organizational ecology through varieties of networks and interaction among organizations. In order to make a difference in climate field,Chinese NGOs firstly needed to improve and enhance their own abilities.
基金This work was supported by NSFC under Grant No.49876011 and 40136010by the Chinese Ministry of Science and Technology under Grant No.2001CCB00500.
文摘Based on the analysis of Levitus data, the climatic states of the warm pool in the Indian Ocean (WPIO) and in the Pacific Ocean (WPPO) are studied. It is found that WPIO has a relatively smaller area, a shallower bottom and a slightly lower seawater temperature than those of WPPO. The horizontal area at different depths, volumes, central positions, and bottom depths of both WPIO and WPPO show quite apparent signals of seasonal variation. The maximum amplitude of WPIO surface area’s seasonal variation is 58% larger over the annual mean value. WPIO’s maximum volume variation amplitude is 66% larger over the annual mean value. The maximum variation amplitudes of the surface area and volume of WPPO are 20. 9% and 20.6% larger over the annual mean value respectively. WPIO and WPPO show different temporal and spatial characteristics mainly due to the different wind fields and restriction of ocean basin geometry. For instance, seasonal northern displacement of WPIO is, to some extent, constrained by the basin of the Indian Ocean, while WPPO moves relatively freely in the longitudinal direction. The influence of WPIO and WPPO over the atmospheric motion must be quite different.
基金supported by National Key Technology R&D Program (Grant No. 2007BAC29B02)National Natural Science Foundation Director Fund (Grant No. 40940008)
文摘By use of 1948-2007 NCEP/NCAR reanalysis monthly geopotential data, a set of circulation indices are defined to characterize the polar vortex at 10 hPa in the Southern Hemisphere, including area-（S）, intensity-（P） and centre position-（λc , φc） indices. Sea-sonal variation, interannual anomalies and their possible causes of 10 hPa polar vortex in the Southern Hemisphere are analyzed by using these indices, the relationship between 10 hPa polar vortex strength and the Antarctic Oscillation are analyzed as well. The results show that： （1） the polar region at 10 hPa in the Southern Hemisphere is controlled by anticyclone （cyclone） from Dec. to Jan. （from Mar. to Oct.）, Feb. and Nov. are circulation transition seasons. （2） Intensity index （P） and area index （S） of anticy-clone （cyclone） in Jan. （Jul.） show a significant spike in the late 1970s, the anticyclone （cyclone） enhances （weakens） from ex-tremely weak （strong） oscillation to near the climatic mean before a spike, anticyclone tends to the mean state from very strong oscillation and cyclone oscillates in the weaker state after the spike. （3） There is significant interdecadal change for the anticyclone center in Jan., while markedly interannual variation for cyclone center in July. （4） The ozone anomalies can cause the interannual anomaly of the polar anticyclone at 10 hPa in the Southern Hemisphere in Jan. （positive correlation between them）, but it is not related to the polar cyclone anomalies. （5） There is notable negative correlation between the polar vortex intensity index P and the Antarctic Oscillation index （AAOI）, thus AAOI can be represented by P.
