This study focuses on examining the characteristics of climate factors and extreme climate events in Northeast China during 1961- 2010 by using daily data from 104 stations, including surface air temperature, precipit...This study focuses on examining the characteristics of climate factors and extreme climate events in Northeast China during 1961- 2010 by using daily data from 104 stations, including surface air temperature, precipitation, wind speed, sunshine duration, and snow depth. Results show that annual mean temperature increased at a significant rate of 0.35℃ per decade, most notably in the Lesser Khingan Mountains and in winter. Annual rainfall had no obvious linear trend, while rainy days had a significant decreasing trend. So, the rain intensity increased. High-temperature days had a weak increasing trend, and low-temperature days and cold wave showed significant decreasing trends with rates of 3.9 d per decade and -0.64 times per decade, respectively. Frequency and spatial scope of low-temperature hazard reduced significantly. Warm days and warm nights significantly increased at 1.0 and 2.4 d per decade, while cold days and cold nights decreased significantly at -1.8 and -4.1 d per decade, respectively. The nighttime warming rate was much higher than that for daytime, indicating that nighttime warming had a greater contribution to the overall warming trend than daytime warming. The annual mean wind speed, gale days, and sunshine duration had significant decreasing trends at rates of-0.21 m s-1 per decade, -4.0 d per decade and -43.3 h per decade, respectively. The snow cover onset dates postponed at a rate of 1.2 d per decade, and the snow cover end date advanced at 1.5 d per decade, which leads to shorter snow cover duration by -2.7 d per decade. Meanwhile, the maximum snow depth decreased at -0.52 cm per decade. In addition, the snow cover duration shows a higher correlation with precipitation than with temperature, which suggests that precipitation plays a more important role in maintaining snow cover duration than temperature.展开更多
Daily climate data at 110 stations during 1961-2010 were selected to examine the changing characteristics of climate factors and extreme climate events in South China. The annual mean surface air temperature has incre...Daily climate data at 110 stations during 1961-2010 were selected to examine the changing characteristics of climate factors and extreme climate events in South China. The annual mean surface air temperature has increased significantly by 0.16℃ per decade, most notably in the Pearl River Delta and in winter. The increase rate of the annual extreme minimum temperature (0.48℃ per decade) is over twice that of the annual extreme maximum temperature (0.20℃ per decade), and the increase of the mean temperature is mainly the result of the increase of the extreme minimum temperature. The increase rate of high-temperature days (1.1 d per decade) is close to the decrease rate of low-temperature days (-1.3 d per decade). The rainfall has not shown any significant trend, but the number of rainy days has decreased and the rain intensity has increased. The regional mean sunshine duration has a significant decreasing trend of -40.9 h per decade, and the number of hazy days has a significant increasing trend of 6.3 d per decade. The decrease of sunshine duration is mainly caused by the increase of total cloud, not by the increase of hazy days in South China. Both the regional mean pan evaporation and mean wind speed have significant decreasing trends of -65.9 mm per decade and -0.11 m s-1 per decade, respectively. The decrease of both sunshine duration and mean wind speed plays an important role in the decrease of pan evaporation. The number of landing tropical cyclones has an insignificant decreasing trend of -0.6 per decade, but their intensities show a weak increasing trend. The formation location of tropical cyclones landing in South China has converged towards 10-19°N, and the landing position has shown a northward trend. The date of the first landfall tropical cyclone postpones 1.8 d per decade, and the date of the last landfall advances 3.6 d per decade, resulting in reduction of the typhoon season by 5.4 d per decade.展开更多
During phase II of the Regional Climate Model Inter-comparison Project （RMIP） for Asia, the Asian climate was estimated from July 1988 to December 1998 using six climate models. In this paper, the abilities of six c...During phase II of the Regional Climate Model Inter-comparison Project （RMIP） for Asia, the Asian climate was estimated from July 1988 to December 1998 using six climate models. In this paper, the abilities of six climate models to simulate several important ex- treme climate events in China during the last years of the last century were analyzed. The modeled results for the intensity of the precipitation anomaly over the Yang- tze-Huaihe Valley during the summers of 1991 and 1998 were weaker than the observed values. The positive pre- cipitation anomaly responsible for a catastrophic flood in 1991 was well reproduced in almost all simulation results, but the intensity and range of the precipitation anomaly in 1998 were weaker in the modeled results. The spatial dis- tribution of extreme climate events in 1997, when severe drought affected North China and flood impacted South China, was reproduced by most of the regional models because the anomaly of the large-scale background field was well-simulated, despite poor simulation of high temperature areas in the north during the summer by all models.展开更多
Daily maximum/minimum temperature and precipitation data from 35 weather stations in Xinjiang during 1961-2010 were examined using kriging spatial analysis, linear tendency estimation, and correlation analysis. Tempor...Daily maximum/minimum temperature and precipitation data from 35 weather stations in Xinjiang during 1961-2010 were examined using kriging spatial analysis, linear tendency estimation, and correlation analysis. Temporal trends and spatial distribution patterns of extreme temperature and precipitation in this area were then analyzed using 12 extreme temperature and 7 extreme precipitation indices. The following results were obtained. 1) Over the past 50 years, extreme cold indices, excepting the monthly maximum temperature minimum value and monthly extreme minimum temperature, showed slight decreasing trends. These indices include the maximum number of consecutive frost days, icy days, cold-nighttime days, and cold-daytime days. 2) Extreme warm events generally showed significant increasing trends (P < 0.01), including the indices of summertime days, warm-nighttime days, warm-daytime days, monthly extreme maximum temperature, and monthly minimum temperature maximum value. 3) The spatial distributions of threshold values of extreme warm and cold events showed notable regional differences. A reducing trend of extreme cold events and an increase in extreme warm events has occurred mainly in northern Xinjiang. 4) For the past 50 years, six extreme precipitation indices, aside from consecutive dry days, showed significant increasing trends in Xinjiang (P < 0.05) and notable differences in spatial distribution. The increase in extreme precipitation events was more rapid at northern than at southern sites. Extreme precipitation intensity was greater in mountainous areas, and precipitation frequency increased in the plain region. 5) Factor analysis revealed good correlations among extreme temperature indices, excepting extreme temperature days.展开更多
Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a m...Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and intensities.China's grassland ecosystem includes most grassland types and is a good choice for studying this issue.This study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.展开更多
Climate change studies are diverse with no single study giving a comprehensive review of climate change impacts,adaptation strategies,and policy development in West Africa.The unavailability of an all-inclusive study ...Climate change studies are diverse with no single study giving a comprehensive review of climate change impacts,adaptation strategies,and policy development in West Africa.The unavailability of an all-inclusive study to serve as a guide for practitioners affects the effectiveness of climate change adaptation strategies proposed and adopted in the West African sub-region.The purpose of this study was to review the impacts of climate change risks on the crop,fishery,and livestock sectors,as well as the climate change adaptation strategies and climate-related policies aimed at helping to build resilient agricultural production systems in West Africa.The review process followed a series of rigorous stages until the final selection of 56 articles published from 2009 to 2023.Generally,the results highlighted the adverse effects of climate change risks on food security.We found a continuous decline in food crop production.Additionally,the livestock sector experienced morbidity and mortality,as well as reduction in meat and milk production.The fishery sector recorded loss of fingerlings,reduction in fish stocks,and destruction of mariculture and aquaculture.In West Africa,climate-smart agriculture technologies,physical protection of fishing,and inclusion of gender perspectives in programs appear to be the major adaptation strategies.The study therefore recommends the inclusion of ecosystem and biodiversity restoration,weather insurance,replacement of unsafe vessels,and strengthening gender equality in all climate change mitigation programs,as these will help to secure enough food for present and future generations.展开更多
Soybean is an important oil crop.Agro-climatic resources and extreme climate events during the growing season directly affect the crop growth and grain yield.In this study,we used historical climate data and phenology...Soybean is an important oil crop.Agro-climatic resources and extreme climate events during the growing season directly affect the crop growth and grain yield.In this study,we used historical climate data and phenology observation data to investigate the spatial distributions and temporal trends of agro-climatic resources and extreme climate events during the growing season for soybean in Northeast China(NEC).The results showed that during the soybean growing season,the thermal time increased while both the effective precipitation and photosynthetically active radiation(PAR)decreased.Within the growing season,the thermal time increased by 44.0°C day decade–1 during the vegetative stage but decreased by 16.5°C day decade–1 during the reproductive stage;the effective precipitation increased by 1.8 mm decade–1 during the vegetative stage but decreased by 7.3 mm decade–1 during the reproductive stage;PAR decreased by 6.5 and 11.9 MJ m–2 decade–1 during the vegetative and reproductive stages.The frequency of extreme cold days showed a decreasing trend during the four study phases of sowing to emergence,sowing–flowering,15 days before flowering–flowering,and pod to physiological maturity.During the soybean growing season,the frequency of extreme heat days and the maximum number of consecutive dry days(CDD)increased,and the maximum number of consecutive wet days(CWD)and heavy precipitation days decreased.The results of this study could be used in selecting optimal management in soybean production in order to take advantage of beneficial climatic elements.展开更多
The China Meteorological Administration recently released China Polar Climate Change Annual Report(2022)in Chinese,with the following main conclusions.Using the China Reanalysis-40 dataset(CRA-40),rapid warming has be...The China Meteorological Administration recently released China Polar Climate Change Annual Report(2022)in Chinese,with the following main conclusions.Using the China Reanalysis-40 dataset(CRA-40),rapid warming has been observed in the Antarctic Peninsula and West Antarctica since 1979,with some parts of East Antarctica also experiencing warming.In 2022,the regional average temperature in Antarctica based on observational data was close to the long-term average(1991-2020).The Arctic,on the other hand,has experienced a warming trend at a rate of 0.63℃per decade from 1979 to 2022 based on CRA-40,which is 3.7 times the global mean during the same period(0.17℃per decade).In 2022,the overall temperature in the Arctic,using station data,was 1.10℃above the long-term average(1991-2020).In recent years,both the Antarctic and Arctic regions have witnessed an increase in the frequency and intensity of extreme weather events.In 2022,based on the sea ice extent from National Snow and Ice Data Center,USA,Antarctic sea ice reached its lowest extent on record since 1979,and on 18 March,the most rapid surface warming event ever recorded on Earth occurred in the Antarctic,with a temperature increase of 49℃within 3 d.This report has been integrated into China's National Climate Change Bulletin system,to contribute to raising public awareness of polar climate change and providing valuable scientific references to address climate change.展开更多
Gale in Turpan On February 28,a gale(up to 41.8 meters per second)in Turpan, Xinjiang Uygur Autonomous Region blew 11 train cars off the track,killing four and disrupting rail traffic for nine hours. Typhoon Sepat On ...Gale in Turpan On February 28,a gale(up to 41.8 meters per second)in Turpan, Xinjiang Uygur Autonomous Region blew 11 train cars off the track,killing four and disrupting rail traffic for nine hours. Typhoon Sepat On August 19,Typhoon Sepat slammed into southern Fujian Province after hitting Taiwan on August 18.The ensuing storms,downpours and landslides affected 114.2 million people in seven southern provinces,and left a death toll of 51 and direct economic losses of 10.3 billion yuan($1.4 billion).展开更多
Polar climate systems have experienced a number of dramatic changes （Wang et al., 2017; Turner et al., 2016; Gordon, 2014; Rignot et al., 2013; Meier et al., 2012; Kwok and Rothrock, 2009; Thompson and Solomon, 2002...Polar climate systems have experienced a number of dramatic changes （Wang et al., 2017; Turner et al., 2016; Gordon, 2014; Rignot et al., 2013; Meier et al., 2012; Kwok and Rothrock, 2009; Thompson and Solomon, 2002）, which have influenced climatic conditions across large parts of the globe through large-scale atmospheric and oceanic teleconnections （Dou and Wu, 2018; Zhang et al., 2018;展开更多
This report provides a broad overview of the climate and the major weather and climate events over the Three Gorges Region of the Yangtze River(TGR)in 2019.The year 2019,a 0.3℃ warmer year than normal,had a colder wi...This report provides a broad overview of the climate and the major weather and climate events over the Three Gorges Region of the Yangtze River(TGR)in 2019.The year 2019,a 0.3℃ warmer year than normal,had a colder winter and warmer spring,summer,and autumn.Annual precipitation in 2019 was 13%less than normal.Below average normal rainfall amounts were received in all four seasons,with 28%and 16%less-than-normal in winter and summer,respectively.The annual mean wind speed in the TGR was higher than normal,and relative humidity was near normal for all four seasons.The intensity of acid rain in 2019 was the weakest since 1999.The major climate events and meteorological disasters in the TGR in 2019 included heat waves,drought,and rainstorms.Heat waves occurred frequently and persisted for long durations.Summer and autumn drought occurred in central and eastern regions of the TGR.The autumn rains of West China occurred earlier this year,which brought much more rainfall than normal in central and western regions of the TGR.展开更多
This report provides a summary of the climate, as well as the major weather and climate events,over the Three Gorges Region of the Yangtze River(TGR) in 2018. The annual mean temperature over the TGR in 2018 was 0.2℃...This report provides a summary of the climate, as well as the major weather and climate events,over the Three Gorges Region of the Yangtze River(TGR) in 2018. The annual mean temperature over the TGR in 2018 was 0.2℃ above normal, and precipitation was near normal. Seasonal highlights included a second warmest spring in the 58-year period of records, with abundant rainfall, which resulted in the wettest March on record. Furthermore, this was the fourth-warmest summer on record in the TGR, which contributed a higher-than-normal number of hot days in2018. Precipitation was 17% and 30% less-than-normal in winter and summer, and 40% and 6% above average in spring and autumn, respectively. The annual mean wind speed in the TGR was higher than normal, and the annual mean relative humidity was near normal. The intensity of acid rain was relatively weak, being the second-weakest year since 1999. The major meteorological disaster types in the TGR include heat waves, drought, rainstorms and flooding, freezing rain, and snow. Heat waves occurred early in the summer and persisted for long durations with strong intensities. Long-term precipitation deficits resulted in drought conditions in summer 2018 across most regions of the TGR. Frequent heavy rainfall caused urban waterlogging. The early-year and late-year cold snaps were accompanied by heavy snowfall and rain over some locations across the TGR, which had adverse impacts on transportation, agriculture, electricity, and people’s lives.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
The present study focused on statistical analysis of interannual, interdecadal variations of climate variables and extreme climate events during the period of 1961-2010 using observational data from 376 meteorological...The present study focused on statistical analysis of interannual, interdecadal variations of climate variables and extreme climate events during the period of 1961-2010 using observational data from 376 meteorological stations uniformly distributed across Southwest China, which includes Yunnan, Guizhou, Chongqing, Sichuan and Tibet. It was found that temperatures in most of the region were warming and this was especially evident for areas at high elevation. The warming was mostly attributable to the increase in annual mean minimum temperature. The characteristics of high temperature/heat waves are increase in frequency, prolonged duration, and weakened intensity. Annual precipitation showed a weak decreasing trend and drier in the east and more rainfall in the west. The precipitation amount in flood season was declining markedly in the whole region; rainfall from extreme heavy precipitation did not change much, and the portion of annual precipitation contributed by extreme heavy precipitation had an increasing trend; annual non-rainy days and the longest consecutive non-rainy days were both increasing; the extreme drought had a decreasing trend since the 1990s; the autumn-rain days displayed a downward fluctuation with apparent periodicity and intermittency. The number of southwestern vortices was decreasing whereas the number of moving vortices increased.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
Climate events pose major challenges to food production and the livelihoods of rural inhabitants in northern Laos, where upland rice using swidden production is an important crop. The onset of the rainy season in this...Climate events pose major challenges to food production and the livelihoods of rural inhabitants in northern Laos, where upland rice using swidden production is an important crop. The onset of the rainy season in this area is one such climate event, and it has occurred earlier and with less regularity in recent years. Not all households are able to cope with these changes. This study examines the ability of local farmers to cope with rice insufficiency. This investigation also clarifies household strategies in dealing with the climate event. We randomly interviewed 63 of 95 household heads, and performed a paired sample t test to examine the significance of differences in three household groups between the 2010 normal climate and the 2011 climate event. The groups were categorized according to rice selfsufficiency in 2011: groups I are households with rice self-sufficiency, group II are those facing a rice shortage of up to 3 months, and group III are those with insufficient rice for over 3 months. We also conducted a one-way ANOVA to examine the significance of differences in livelihood strategies among the three groups. We found that the household labor force was the most important factor in enhancing the villagers' ability to deal with the climate event and that the level of impact of that event shaped their coping strategies. Households with substantial labor force had more options for coping strategies than those with smaller ones. The villagers faced different levels of impact and adopted differentcoping strategies accordingly. Non-timber forest product collection was the principle livelihood strategy in response to non-climate factors such as education, access to health services, provision of equipment and clothing, and overcoming the impact of the climate event. Households heavily affected by the early rainy season onset tended to engage in intensive activities such as off-farm activity and outside work, rather than their major livelihood activities in the village(upland crop and livestock production).展开更多
The spatial and temporal variations of some important near-surface climate parameters and extreme climate events in North China during 1961-2010 are analyzed by using 94 meteorological stations＇ data in the study are...The spatial and temporal variations of some important near-surface climate parameters and extreme climate events in North China during 1961-2010 are analyzed by using 94 meteorological stations＇ data in the study area. Results show that the annual mean surface air temperature in North China increased at the rate of 0.36℃ per decade, higher than the national average in the same period. Increasing was particularly significant since the mid-1980s, with maximum increase in the middle and northeastern parts of Inner Mongolia. Increasing rate of the annual mean minimum temperature is much higher than that of the maximum temperature, which results in the decrease of the annual mean diurnal temperature range. Noticeable decrease is also observed in the frequency of cold wave. Annual precipitation shows a slight decreasing trend, with more pronounced decrease in southern Shanxi and eastern Hebei provinces, which is mainly represented as decreasing in contribution rates of rainstorm and heavy storm in flood-season （May to September）. During 1961 -2010, North China is characterized by a noticeable reduction in annual extreme precipitation, and an increase in high-temperature days over most parts, as well as more frequent droughts. There are remarkable reductions in annual sunshine duration and mean wind speed, associated with the most significant reduction of mean wind speed in midwestern and eastern parts of Inner Mongolia. Meanwhile, North China has experienced a noticeable decrease/increase in annual mean sanddust/haze days during the study period. However, there is no significant trend in fog days, except a pronounced decrease since the 1990s.展开更多
To analyze extreme climatic change features and effects on runoff in the Manas River basin, Xinjiang, data were collected including daily mean temperature, daily highest and lowest temperatures, and daily precipitatio...To analyze extreme climatic change features and effects on runoff in the Manas River basin, Xinjiang, data were collected including daily mean temperature, daily highest and lowest temperatures, and daily precipitation from six meteorological stations in the Manas River basin as well as daily runoff data from the Kensiwate hydrologic stations during 1960-2010. By adopting the threshold value of extreme climatic events defined by ET ALDDMI and with the aid of nonparametric statistical tests, Pearson III methods, and others, the effect of extreme climatic events on extreme runoff in the past 50 years in the Manas River basin, Xinjiang, was analyzed. The results showed that in the past 50 years, 1) extreme warming events (annual extreme maximum temperature, warm-day and warm-night index) have risen significantly (P < 0.05). Among these the warm-day and warm-night indices decreased abruptly in 2001 and 1996, respectively. With respect to extreme cold events (annual extreme minimum temperature, cold-day and cold-night indices), the extreme minimum temperature was high after 1976, and the cold-day index weakened significantly, similar to the cold-night index. 2) Except for the continuous drought days (CDD), the other five indices of extreme precipitation events appeared to trend upward, with an abrupt change around 1993. 3) Flood events in 1990, mostly in summer, accounted for 42.9% of the total number of floods since 1960. Floods increased mainly because extremely high summer temperatures increased snowmelt, increasing inflow to the rivers, which combined with more precipitation to cause the increase in summer peak flood discharge.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
Objective A total of 820 million tons of potash reserves are predicted to exist in the Palaeocene-Eocene of the Jianghan Basin. However, the basin history is still unclear concerning the potash enriching conditions a...Objective A total of 820 million tons of potash reserves are predicted to exist in the Palaeocene-Eocene of the Jianghan Basin. However, the basin history is still unclear concerning the potash enriching conditions and mechanism. The Well SKDI is the first exploration well drilled in the Paleogene of Jianghan Basin with continuous coring, which was implemented in the south-central Jiangling Basin in 2013. It is essential to study the Palaeocene-Eocene paleoclimate, to further constrain the extreme draught events and the potash forming conditions.展开更多
基金supported by the Special Climate Change Research Program of China Meteorological Ad-ministration (No.062700s010c01)the Special Scientific Research Fund of Meteorological Public Welfare Profession of China (No.201206024)
文摘This study focuses on examining the characteristics of climate factors and extreme climate events in Northeast China during 1961- 2010 by using daily data from 104 stations, including surface air temperature, precipitation, wind speed, sunshine duration, and snow depth. Results show that annual mean temperature increased at a significant rate of 0.35℃ per decade, most notably in the Lesser Khingan Mountains and in winter. Annual rainfall had no obvious linear trend, while rainy days had a significant decreasing trend. So, the rain intensity increased. High-temperature days had a weak increasing trend, and low-temperature days and cold wave showed significant decreasing trends with rates of 3.9 d per decade and -0.64 times per decade, respectively. Frequency and spatial scope of low-temperature hazard reduced significantly. Warm days and warm nights significantly increased at 1.0 and 2.4 d per decade, while cold days and cold nights decreased significantly at -1.8 and -4.1 d per decade, respectively. The nighttime warming rate was much higher than that for daytime, indicating that nighttime warming had a greater contribution to the overall warming trend than daytime warming. The annual mean wind speed, gale days, and sunshine duration had significant decreasing trends at rates of-0.21 m s-1 per decade, -4.0 d per decade and -43.3 h per decade, respectively. The snow cover onset dates postponed at a rate of 1.2 d per decade, and the snow cover end date advanced at 1.5 d per decade, which leads to shorter snow cover duration by -2.7 d per decade. Meanwhile, the maximum snow depth decreased at -0.52 cm per decade. In addition, the snow cover duration shows a higher correlation with precipitation than with temperature, which suggests that precipitation plays a more important role in maintaining snow cover duration than temperature.
基金supported by the Special Climate Change Research Program of China Meteorological Administration (No. CCSF-09-11, CCSF-09-03, CCSF2011-25, and CCSF201211)the Science and Technology Planning Project of Guangdong province (No.2011A030200021)
文摘Daily climate data at 110 stations during 1961-2010 were selected to examine the changing characteristics of climate factors and extreme climate events in South China. The annual mean surface air temperature has increased significantly by 0.16℃ per decade, most notably in the Pearl River Delta and in winter. The increase rate of the annual extreme minimum temperature (0.48℃ per decade) is over twice that of the annual extreme maximum temperature (0.20℃ per decade), and the increase of the mean temperature is mainly the result of the increase of the extreme minimum temperature. The increase rate of high-temperature days (1.1 d per decade) is close to the decrease rate of low-temperature days (-1.3 d per decade). The rainfall has not shown any significant trend, but the number of rainy days has decreased and the rain intensity has increased. The regional mean sunshine duration has a significant decreasing trend of -40.9 h per decade, and the number of hazy days has a significant increasing trend of 6.3 d per decade. The decrease of sunshine duration is mainly caused by the increase of total cloud, not by the increase of hazy days in South China. Both the regional mean pan evaporation and mean wind speed have significant decreasing trends of -65.9 mm per decade and -0.11 m s-1 per decade, respectively. The decrease of both sunshine duration and mean wind speed plays an important role in the decrease of pan evaporation. The number of landing tropical cyclones has an insignificant decreasing trend of -0.6 per decade, but their intensities show a weak increasing trend. The formation location of tropical cyclones landing in South China has converged towards 10-19°N, and the landing position has shown a northward trend. The date of the first landfall tropical cyclone postpones 1.8 d per decade, and the date of the last landfall advances 3.6 d per decade, resulting in reduction of the typhoon season by 5.4 d per decade.
基金supported by the National Key Program for Developing Basic Sciences of China (Grant No.2009CB723904)the General Project of the National Natural Science Foundation of China (Grant No. 40975048)the Innovation Key Program of the Chinese Academy of Sciences (Grant No.KGCX2-YW-356)
文摘During phase II of the Regional Climate Model Inter-comparison Project （RMIP） for Asia, the Asian climate was estimated from July 1988 to December 1998 using six climate models. In this paper, the abilities of six climate models to simulate several important ex- treme climate events in China during the last years of the last century were analyzed. The modeled results for the intensity of the precipitation anomaly over the Yang- tze-Huaihe Valley during the summers of 1991 and 1998 were weaker than the observed values. The positive pre- cipitation anomaly responsible for a catastrophic flood in 1991 was well reproduced in almost all simulation results, but the intensity and range of the precipitation anomaly in 1998 were weaker in the modeled results. The spatial dis- tribution of extreme climate events in 1997, when severe drought affected North China and flood impacted South China, was reproduced by most of the regional models because the anomaly of the large-scale background field was well-simulated, despite poor simulation of high temperature areas in the north during the summer by all models.
文摘Daily maximum/minimum temperature and precipitation data from 35 weather stations in Xinjiang during 1961-2010 were examined using kriging spatial analysis, linear tendency estimation, and correlation analysis. Temporal trends and spatial distribution patterns of extreme temperature and precipitation in this area were then analyzed using 12 extreme temperature and 7 extreme precipitation indices. The following results were obtained. 1) Over the past 50 years, extreme cold indices, excepting the monthly maximum temperature minimum value and monthly extreme minimum temperature, showed slight decreasing trends. These indices include the maximum number of consecutive frost days, icy days, cold-nighttime days, and cold-daytime days. 2) Extreme warm events generally showed significant increasing trends (P < 0.01), including the indices of summertime days, warm-nighttime days, warm-daytime days, monthly extreme maximum temperature, and monthly minimum temperature maximum value. 3) The spatial distributions of threshold values of extreme warm and cold events showed notable regional differences. A reducing trend of extreme cold events and an increase in extreme warm events has occurred mainly in northern Xinjiang. 4) For the past 50 years, six extreme precipitation indices, aside from consecutive dry days, showed significant increasing trends in Xinjiang (P < 0.05) and notable differences in spatial distribution. The increase in extreme precipitation events was more rapid at northern than at southern sites. Extreme precipitation intensity was greater in mountainous areas, and precipitation frequency increased in the plain region. 5) Factor analysis revealed good correlations among extreme temperature indices, excepting extreme temperature days.
基金the National Natural Science Foundation of China(42271289).
文摘Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and intensities.China's grassland ecosystem includes most grassland types and is a good choice for studying this issue.This study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.
文摘Climate change studies are diverse with no single study giving a comprehensive review of climate change impacts,adaptation strategies,and policy development in West Africa.The unavailability of an all-inclusive study to serve as a guide for practitioners affects the effectiveness of climate change adaptation strategies proposed and adopted in the West African sub-region.The purpose of this study was to review the impacts of climate change risks on the crop,fishery,and livestock sectors,as well as the climate change adaptation strategies and climate-related policies aimed at helping to build resilient agricultural production systems in West Africa.The review process followed a series of rigorous stages until the final selection of 56 articles published from 2009 to 2023.Generally,the results highlighted the adverse effects of climate change risks on food security.We found a continuous decline in food crop production.Additionally,the livestock sector experienced morbidity and mortality,as well as reduction in meat and milk production.The fishery sector recorded loss of fingerlings,reduction in fish stocks,and destruction of mariculture and aquaculture.In West Africa,climate-smart agriculture technologies,physical protection of fishing,and inclusion of gender perspectives in programs appear to be the major adaptation strategies.The study therefore recommends the inclusion of ecosystem and biodiversity restoration,weather insurance,replacement of unsafe vessels,and strengthening gender equality in all climate change mitigation programs,as these will help to secure enough food for present and future generations.
基金Supported by the National Key Research and Development Program of China(2019YFA0607402)。
文摘Soybean is an important oil crop.Agro-climatic resources and extreme climate events during the growing season directly affect the crop growth and grain yield.In this study,we used historical climate data and phenology observation data to investigate the spatial distributions and temporal trends of agro-climatic resources and extreme climate events during the growing season for soybean in Northeast China(NEC).The results showed that during the soybean growing season,the thermal time increased while both the effective precipitation and photosynthetically active radiation(PAR)decreased.Within the growing season,the thermal time increased by 44.0°C day decade–1 during the vegetative stage but decreased by 16.5°C day decade–1 during the reproductive stage;the effective precipitation increased by 1.8 mm decade–1 during the vegetative stage but decreased by 7.3 mm decade–1 during the reproductive stage;PAR decreased by 6.5 and 11.9 MJ m–2 decade–1 during the vegetative and reproductive stages.The frequency of extreme cold days showed a decreasing trend during the four study phases of sowing to emergence,sowing–flowering,15 days before flowering–flowering,and pod to physiological maturity.During the soybean growing season,the frequency of extreme heat days and the maximum number of consecutive dry days(CDD)increased,and the maximum number of consecutive wet days(CWD)and heavy precipitation days decreased.The results of this study could be used in selecting optimal management in soybean production in order to take advantage of beneficial climatic elements.
基金supported by the National Science Foundation of China (Grant no.42122047)the Basic Fund of the Chinese Academy of Meteorological Sciences (Grant nos.2021Z006 and 2023Z025)。
文摘The China Meteorological Administration recently released China Polar Climate Change Annual Report(2022)in Chinese,with the following main conclusions.Using the China Reanalysis-40 dataset(CRA-40),rapid warming has been observed in the Antarctic Peninsula and West Antarctica since 1979,with some parts of East Antarctica also experiencing warming.In 2022,the regional average temperature in Antarctica based on observational data was close to the long-term average(1991-2020).The Arctic,on the other hand,has experienced a warming trend at a rate of 0.63℃per decade from 1979 to 2022 based on CRA-40,which is 3.7 times the global mean during the same period(0.17℃per decade).In 2022,the overall temperature in the Arctic,using station data,was 1.10℃above the long-term average(1991-2020).In recent years,both the Antarctic and Arctic regions have witnessed an increase in the frequency and intensity of extreme weather events.In 2022,based on the sea ice extent from National Snow and Ice Data Center,USA,Antarctic sea ice reached its lowest extent on record since 1979,and on 18 March,the most rapid surface warming event ever recorded on Earth occurred in the Antarctic,with a temperature increase of 49℃within 3 d.This report has been integrated into China's National Climate Change Bulletin system,to contribute to raising public awareness of polar climate change and providing valuable scientific references to address climate change.
文摘Gale in Turpan On February 28,a gale(up to 41.8 meters per second)in Turpan, Xinjiang Uygur Autonomous Region blew 11 train cars off the track,killing four and disrupting rail traffic for nine hours. Typhoon Sepat On August 19,Typhoon Sepat slammed into southern Fujian Province after hitting Taiwan on August 18.The ensuing storms,downpours and landslides affected 114.2 million people in seven southern provinces,and left a death toll of 51 and direct economic losses of 10.3 billion yuan($1.4 billion).
基金funded by the Fundamental Research Funds for the Central Universities (Grant nos.2017B04814,2017B20714),Hohai UniversityState Key Laboratory of Satellite Ocean Environment Dynamics+1 种基金supported by the Global Change Research Program of China (Grant no.2015CB953904)the National Natural Science Foundation of China (NSFC,Grant no.41876220)
文摘Polar climate systems have experienced a number of dramatic changes （Wang et al., 2017; Turner et al., 2016; Gordon, 2014; Rignot et al., 2013; Meier et al., 2012; Kwok and Rothrock, 2009; Thompson and Solomon, 2002）, which have influenced climatic conditions across large parts of the globe through large-scale atmospheric and oceanic teleconnections （Dou and Wu, 2018; Zhang et al., 2018;
基金This study was supported by the National Key R&D Program of China[grant numbers 2017YFC1502402,2017YFD0300201,and 2017YFA0605004]the funds of comprehensive monitoring of the Three Gorges Project,which was financed by the Ministry of Water Resources of China.
文摘This report provides a broad overview of the climate and the major weather and climate events over the Three Gorges Region of the Yangtze River(TGR)in 2019.The year 2019,a 0.3℃ warmer year than normal,had a colder winter and warmer spring,summer,and autumn.Annual precipitation in 2019 was 13%less than normal.Below average normal rainfall amounts were received in all four seasons,with 28%and 16%less-than-normal in winter and summer,respectively.The annual mean wind speed in the TGR was higher than normal,and relative humidity was near normal for all four seasons.The intensity of acid rain in 2019 was the weakest since 1999.The major climate events and meteorological disasters in the TGR in 2019 included heat waves,drought,and rainstorms.Heat waves occurred frequently and persisted for long durations.Summer and autumn drought occurred in central and eastern regions of the TGR.The autumn rains of West China occurred earlier this year,which brought much more rainfall than normal in central and western regions of the TGR.
基金supported by the National Key R&D Program of China [grant numbers 2017YFC1502402,2017YFD0300201 and2017YFA0605004]the funds of comprehensive monitoring of the Three Gorges Project,which was financed by the Ministry of Water Resources of China.
文摘This report provides a summary of the climate, as well as the major weather and climate events,over the Three Gorges Region of the Yangtze River(TGR) in 2018. The annual mean temperature over the TGR in 2018 was 0.2℃ above normal, and precipitation was near normal. Seasonal highlights included a second warmest spring in the 58-year period of records, with abundant rainfall, which resulted in the wettest March on record. Furthermore, this was the fourth-warmest summer on record in the TGR, which contributed a higher-than-normal number of hot days in2018. Precipitation was 17% and 30% less-than-normal in winter and summer, and 40% and 6% above average in spring and autumn, respectively. The annual mean wind speed in the TGR was higher than normal, and the annual mean relative humidity was near normal. The intensity of acid rain was relatively weak, being the second-weakest year since 1999. The major meteorological disaster types in the TGR include heat waves, drought, rainstorms and flooding, freezing rain, and snow. Heat waves occurred early in the summer and persisted for long durations with strong intensities. Long-term precipitation deficits resulted in drought conditions in summer 2018 across most regions of the TGR. Frequent heavy rainfall caused urban waterlogging. The early-year and late-year cold snaps were accompanied by heavy snowfall and rain over some locations across the TGR, which had adverse impacts on transportation, agriculture, electricity, and people’s lives.
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supported by the special climate change in 2010 of the China Meteorological Administration (No. ccfs-2010)the National Natural Science Foundation of China (No. 41275097)
文摘The present study focused on statistical analysis of interannual, interdecadal variations of climate variables and extreme climate events during the period of 1961-2010 using observational data from 376 meteorological stations uniformly distributed across Southwest China, which includes Yunnan, Guizhou, Chongqing, Sichuan and Tibet. It was found that temperatures in most of the region were warming and this was especially evident for areas at high elevation. The warming was mostly attributable to the increase in annual mean minimum temperature. The characteristics of high temperature/heat waves are increase in frequency, prolonged duration, and weakened intensity. Annual precipitation showed a weak decreasing trend and drier in the east and more rainfall in the west. The precipitation amount in flood season was declining markedly in the whole region; rainfall from extreme heavy precipitation did not change much, and the portion of annual precipitation contributed by extreme heavy precipitation had an increasing trend; annual non-rainy days and the longest consecutive non-rainy days were both increasing; the extreme drought had a decreasing trend since the 1990s; the autumn-rain days displayed a downward fluctuation with apparent periodicity and intermittency. The number of southwestern vortices was decreasing whereas the number of moving vortices increased.
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funded by Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research (Kakenhi), Scientific Research (A)
文摘Climate events pose major challenges to food production and the livelihoods of rural inhabitants in northern Laos, where upland rice using swidden production is an important crop. The onset of the rainy season in this area is one such climate event, and it has occurred earlier and with less regularity in recent years. Not all households are able to cope with these changes. This study examines the ability of local farmers to cope with rice insufficiency. This investigation also clarifies household strategies in dealing with the climate event. We randomly interviewed 63 of 95 household heads, and performed a paired sample t test to examine the significance of differences in three household groups between the 2010 normal climate and the 2011 climate event. The groups were categorized according to rice selfsufficiency in 2011: groups I are households with rice self-sufficiency, group II are those facing a rice shortage of up to 3 months, and group III are those with insufficient rice for over 3 months. We also conducted a one-way ANOVA to examine the significance of differences in livelihood strategies among the three groups. We found that the household labor force was the most important factor in enhancing the villagers' ability to deal with the climate event and that the level of impact of that event shaped their coping strategies. Households with substantial labor force had more options for coping strategies than those with smaller ones. The villagers faced different levels of impact and adopted differentcoping strategies accordingly. Non-timber forest product collection was the principle livelihood strategy in response to non-climate factors such as education, access to health services, provision of equipment and clothing, and overcoming the impact of the climate event. Households heavily affected by the early rainy season onset tended to engage in intensive activities such as off-farm activity and outside work, rather than their major livelihood activities in the village(upland crop and livestock production).
基金supported by the Climate Change Special Foundation of China Meteorological Administration(No. CCSF2010-1)
文摘The spatial and temporal variations of some important near-surface climate parameters and extreme climate events in North China during 1961-2010 are analyzed by using 94 meteorological stations＇ data in the study area. Results show that the annual mean surface air temperature in North China increased at the rate of 0.36℃ per decade, higher than the national average in the same period. Increasing was particularly significant since the mid-1980s, with maximum increase in the middle and northeastern parts of Inner Mongolia. Increasing rate of the annual mean minimum temperature is much higher than that of the maximum temperature, which results in the decrease of the annual mean diurnal temperature range. Noticeable decrease is also observed in the frequency of cold wave. Annual precipitation shows a slight decreasing trend, with more pronounced decrease in southern Shanxi and eastern Hebei provinces, which is mainly represented as decreasing in contribution rates of rainstorm and heavy storm in flood-season （May to September）. During 1961 -2010, North China is characterized by a noticeable reduction in annual extreme precipitation, and an increase in high-temperature days over most parts, as well as more frequent droughts. There are remarkable reductions in annual sunshine duration and mean wind speed, associated with the most significant reduction of mean wind speed in midwestern and eastern parts of Inner Mongolia. Meanwhile, North China has experienced a noticeable decrease/increase in annual mean sanddust/haze days during the study period. However, there is no significant trend in fog days, except a pronounced decrease since the 1990s.
文摘To analyze extreme climatic change features and effects on runoff in the Manas River basin, Xinjiang, data were collected including daily mean temperature, daily highest and lowest temperatures, and daily precipitation from six meteorological stations in the Manas River basin as well as daily runoff data from the Kensiwate hydrologic stations during 1960-2010. By adopting the threshold value of extreme climatic events defined by ET ALDDMI and with the aid of nonparametric statistical tests, Pearson III methods, and others, the effect of extreme climatic events on extreme runoff in the past 50 years in the Manas River basin, Xinjiang, was analyzed. The results showed that in the past 50 years, 1) extreme warming events (annual extreme maximum temperature, warm-day and warm-night index) have risen significantly (P < 0.05). Among these the warm-day and warm-night indices decreased abruptly in 2001 and 1996, respectively. With respect to extreme cold events (annual extreme minimum temperature, cold-day and cold-night indices), the extreme minimum temperature was high after 1976, and the cold-day index weakened significantly, similar to the cold-night index. 2) Except for the continuous drought days (CDD), the other five indices of extreme precipitation events appeared to trend upward, with an abrupt change around 1993. 3) Flood events in 1990, mostly in summer, accounted for 42.9% of the total number of floods since 1960. Floods increased mainly because extremely high summer temperatures increased snowmelt, increasing inflow to the rivers, which combined with more precipitation to cause the increase in summer peak flood discharge.
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the National Science Foundation of China(Grants No.41502089,41302059 and 41202059)for their financial support
文摘Objective A total of 820 million tons of potash reserves are predicted to exist in the Palaeocene-Eocene of the Jianghan Basin. However, the basin history is still unclear concerning the potash enriching conditions and mechanism. The Well SKDI is the first exploration well drilled in the Paleogene of Jianghan Basin with continuous coring, which was implemented in the south-central Jiangling Basin in 2013. It is essential to study the Palaeocene-Eocene paleoclimate, to further constrain the extreme draught events and the potash forming conditions.
