Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of...Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of the region’s economy.By its nature of intensive water use,agriculture is extremely vulnerable to climate change.Population growth and irrigation development have significantly increased the demand for water in the region.Major climate change issues include melting glaciers and a shrinking snowpack,which are the foundation of the region’s water resources,and a changing precipitation regime.Most glaciers are located in Kyrgyzstan and Tajikistan,leading to transboundary water resource issues.Summer already has extremely high temperatures.Analyses indicate that Central Asia has been warming and precipitation might be increasing.The warming is expected to increase,but its spatial and temporal distribution depends upon specific global scenarios.Projections of future precipitation show significant uncertainties in type,amount,and distribution.Regional Hydroclimate Projects(RHPs)are an approach to studying these issues.Initial steps to develop an RHP began in 2021 with a widely distributed online survey about these climate issues.It was followed up with an online workshop and then,in 2023,an in-person workshop,held in Tashkent,Uzbekistan.Priorities for the Global Energy and Water Exchanges(GEWEX)project for the region include both observations and modeling,as well as development of better and additional precipitation observations,all of which are topics for the next workshop.A well-designed RHP should lead to reductions in critical climate uncertainties in policy-relevant timeframes that can influence decisions on necessary investments in climate adaptation.展开更多
利用世界气候研究计划/全球能量与水循环试验(National Aeronautics and Space Administration/World Climate Research Program,NASA/WCRP)发布的长期地表辐射收支(Global Energy and Water Exchanges-Surface Radiation Budget,GEWEX-...利用世界气候研究计划/全球能量与水循环试验(National Aeronautics and Space Administration/World Climate Research Program,NASA/WCRP)发布的长期地表辐射收支(Global Energy and Water Exchanges-Surface Radiation Budget,GEWEX-SRB)数据产品和中国气象局资料室的地面辐射数据产品,分别获得1984—2007年新疆维吾尔自治区地表全天空向下太阳短波辐射辐照度和地表全天空向下日总辐射曝辐量,对比分析两种数据从而确定卫星数据的精度;在此基础上,进一步分析新疆维吾尔自治区地面太阳辐射的时空分布特征。结果表明:基于GEWEX-SRB卫星观测资料反演的新疆维吾尔自治区太阳辐射明显比地面观测太阳辐射偏高约10%—30%,但两种数据反映的新疆维吾尔自治区太阳辐射的时空分布特征一致。在空间分布上,新疆维吾尔自治区太阳辐射呈明显的经向和纬向分布即太阳辐射由西北向东南方向逐渐递减;在时间分布上,太阳辐射从夏季、春季、秋季至冬季依次减小,从春季到冬季太阳辐射逐步由经向分布向纬向分布转变,夏季太阳辐射变化幅度最大,春季太阳辐射多年变化倾斜率增加最多,冬季太阳辐射多年变化倾斜率增加最少;太阳辐射月变化呈正态分布。展开更多
Environmental influences upon energy balance in areas of different vegetation types （i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and ...Environmental influences upon energy balance in areas of different vegetation types （i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and mixed farmland at Tak in Thailand） in the GEWEX Asian Monsoon Experiment were investigated. The sites we investigated are geographically and climatologically different; and consequently had quite large variations in temperature （T）, water vapor pressure deficit （VPD）, soil moisture （SM）, and precipitation （PPT）. During May- October, the net radiation flux （Rn） （in W·m^-2） was 406.21 at Tak, 365.57 at Kog-Ma, 390.97 at Amdo, 316.65 at Arvaikheer, and 287.10 at Yakutsk. During the growing period, the Rn partitioned into latent heat flux （2E/Rn） was greater than that partitioned into sensible heat flux （H/Rn） at Tak and at Kog-Ma. In contrast, 2E/Rn was lower than H/Rn at Arvaikheer, H/Rn was less than 2E/Rn between DOY 149 and DOY 270 at Amdo, and between DOY 165 and DOY 235 at Yakutsk. The R, partitioned into ground heat flux was generally less than 0.15. The short-wave albedo was 0.12, 0.18, and 0.20 at the forest, mixed land, and grass sites, respectively. At an hourly scale, energy partitions had no correlation with environmental factors, based on average summer half- hourly values. At a seasonal scale energy partitions were linearly correlated （usually p 〈 0.05） with T, VPD, and SM. The 2E/Rn increased with increases in SM, T, and VPD at forest areas. At mixed farmlands, ）λE/Rn generally had positive correlations with SM, T, and VPD, but was restrained at extremely high values of VPD and T. At grasslands, λE/Rn was enhanced with increases of SM and T, but was decreased with VPD.展开更多
遥感辐射产品的验证研究主要集中在单一产品在青藏高原地区和实测数据的比较分析上,缺乏产品之间的相互比较从而无法得知产品的适用性,因此针对整个中国地区对这些产品的适用性进行系统性的比较研究。选取了数据序列较完整的GEWEX-SRB(G...遥感辐射产品的验证研究主要集中在单一产品在青藏高原地区和实测数据的比较分析上,缺乏产品之间的相互比较从而无法得知产品的适用性,因此针对整个中国地区对这些产品的适用性进行系统性的比较研究。选取了数据序列较完整的GEWEX-SRB(Global Energy and Water Cycle Experiment-Surface Radiation Budget)、CERES-EBAF(Clouds and Earth’s Radiant Energy Systems-Energy Balanced and Filled)和GLASS-DSR(Global LAnd Surface Satellite-Downward Shortwave Radiation)3种辐射产品,以相关系数、平均偏差、均方根误差为评价指标在整个中国区域范围内进行精度评价,并且对其精度的时空分布特征进行了研究。研究表明,2000~2007年GEWEX-SRB与CERES-EBAF相比两者具有相似的偏差趋势,低估和高估最严重站点同为峨眉山站和太原站,总体上CERES-EBAF的精度更高。2008~2010年间GLASS-DSR与CERES-EBAF进行对比结果表明CERESEBAF精度要高。总体来说,这3种辐射产品的精度都较高,低估的站点大多地处高海拔地区,其中CERES-EBAF产品时间序列长且精度相对较高,尤其是在中东部及大部分沿海地区精度较高。展开更多
1 引言 国际科学理事会与世界气象组织和其它一些国际组织共同发起组织的大型科学计划——“全球能量与水循环试验(Global Energy and Water cycle EXperiment简称:GEWEX)”是本世纪末世界气候研究计划中的一个主要计划,是为研究气候异...1 引言 国际科学理事会与世界气象组织和其它一些国际组织共同发起组织的大型科学计划——“全球能量与水循环试验(Global Energy and Water cycle EXperiment简称:GEWEX)”是本世纪末世界气候研究计划中的一个主要计划,是为研究气候异常,进行长期预报和防灾减灾,保证粮食生产为目的而设立的世界性研究计划。该项始于1989年,预计到2005年完成的计划,在全球范围内共确定了德国波罗的海、美国密西西比河、亚洲、非洲和南美亚马逊河5大试验区,亚洲季风试验(GEWEX Asian Monsoon Experiment简称:GAME)计划是其中之一。展开更多
In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment(WCRP/GEWEX/GAME/HUBEX: World Climate Research Program/Global Energy and ...In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment(WCRP/GEWEX/GAME/HUBEX: World Climate Research Program/Global Energy and Water Cycle Experiment/Asian Monsoon Experiment/Huaihe River Basin Energy and Water Cycle Experiment) in the Huaihe River basin, Anhui Province of China. The main objective of this field experiment(HUBEX)was to investigate the multiple-scale structure characteristics, life cycles, and genesis and development mechanisms of the Meiyu system in East Asia as well as the cause of related flooding disasters. It was a joint China-Japan cooperative meteorological and hydrological observation experiment. On the basis of intensive observations, scientists from the two countries conducted follow-up investigations through collating and compiling data and performing scientific analysis during the following five years. It can be concluded that the HUBEX project has yielded comprehensive and remarkable achievements. This paper introduces the major scientific results derived from this field experiment and the ensuing investigations, and reassesses their merits and shortages for the purpose of providing useful experience and proposing new research targets as well as prospects for the initiation of a new joint scientific Meiyu experiment in the middle and lower Yangtze River basin.展开更多
基金The National Research University Tashkent Institute of Irrigation and Agricultural Mechanization Engineers of Uzbekistan hosted and provided financial support for the in-person workshop in May of 2023
文摘Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of the region’s economy.By its nature of intensive water use,agriculture is extremely vulnerable to climate change.Population growth and irrigation development have significantly increased the demand for water in the region.Major climate change issues include melting glaciers and a shrinking snowpack,which are the foundation of the region’s water resources,and a changing precipitation regime.Most glaciers are located in Kyrgyzstan and Tajikistan,leading to transboundary water resource issues.Summer already has extremely high temperatures.Analyses indicate that Central Asia has been warming and precipitation might be increasing.The warming is expected to increase,but its spatial and temporal distribution depends upon specific global scenarios.Projections of future precipitation show significant uncertainties in type,amount,and distribution.Regional Hydroclimate Projects(RHPs)are an approach to studying these issues.Initial steps to develop an RHP began in 2021 with a widely distributed online survey about these climate issues.It was followed up with an online workshop and then,in 2023,an in-person workshop,held in Tashkent,Uzbekistan.Priorities for the Global Energy and Water Exchanges(GEWEX)project for the region include both observations and modeling,as well as development of better and additional precipitation observations,all of which are topics for the next workshop.A well-designed RHP should lead to reductions in critical climate uncertainties in policy-relevant timeframes that can influence decisions on necessary investments in climate adaptation.
文摘利用世界气候研究计划/全球能量与水循环试验(National Aeronautics and Space Administration/World Climate Research Program,NASA/WCRP)发布的长期地表辐射收支(Global Energy and Water Exchanges-Surface Radiation Budget,GEWEX-SRB)数据产品和中国气象局资料室的地面辐射数据产品,分别获得1984—2007年新疆维吾尔自治区地表全天空向下太阳短波辐射辐照度和地表全天空向下日总辐射曝辐量,对比分析两种数据从而确定卫星数据的精度;在此基础上,进一步分析新疆维吾尔自治区地面太阳辐射的时空分布特征。结果表明:基于GEWEX-SRB卫星观测资料反演的新疆维吾尔自治区太阳辐射明显比地面观测太阳辐射偏高约10%—30%,但两种数据反映的新疆维吾尔自治区太阳辐射的时空分布特征一致。在空间分布上,新疆维吾尔自治区太阳辐射呈明显的经向和纬向分布即太阳辐射由西北向东南方向逐渐递减;在时间分布上,太阳辐射从夏季、春季、秋季至冬季依次减小,从春季到冬季太阳辐射逐步由经向分布向纬向分布转变,夏季太阳辐射变化幅度最大,春季太阳辐射多年变化倾斜率增加最多,冬季太阳辐射多年变化倾斜率增加最少;太阳辐射月变化呈正态分布。
文摘Environmental influences upon energy balance in areas of different vegetation types （i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and mixed farmland at Tak in Thailand） in the GEWEX Asian Monsoon Experiment were investigated. The sites we investigated are geographically and climatologically different; and consequently had quite large variations in temperature （T）, water vapor pressure deficit （VPD）, soil moisture （SM）, and precipitation （PPT）. During May- October, the net radiation flux （Rn） （in W·m^-2） was 406.21 at Tak, 365.57 at Kog-Ma, 390.97 at Amdo, 316.65 at Arvaikheer, and 287.10 at Yakutsk. During the growing period, the Rn partitioned into latent heat flux （2E/Rn） was greater than that partitioned into sensible heat flux （H/Rn） at Tak and at Kog-Ma. In contrast, 2E/Rn was lower than H/Rn at Arvaikheer, H/Rn was less than 2E/Rn between DOY 149 and DOY 270 at Amdo, and between DOY 165 and DOY 235 at Yakutsk. The R, partitioned into ground heat flux was generally less than 0.15. The short-wave albedo was 0.12, 0.18, and 0.20 at the forest, mixed land, and grass sites, respectively. At an hourly scale, energy partitions had no correlation with environmental factors, based on average summer half- hourly values. At a seasonal scale energy partitions were linearly correlated （usually p 〈 0.05） with T, VPD, and SM. The 2E/Rn increased with increases in SM, T, and VPD at forest areas. At mixed farmlands, ）λE/Rn generally had positive correlations with SM, T, and VPD, but was restrained at extremely high values of VPD and T. At grasslands, λE/Rn was enhanced with increases of SM and T, but was decreased with VPD.
文摘遥感辐射产品的验证研究主要集中在单一产品在青藏高原地区和实测数据的比较分析上,缺乏产品之间的相互比较从而无法得知产品的适用性,因此针对整个中国地区对这些产品的适用性进行系统性的比较研究。选取了数据序列较完整的GEWEX-SRB(Global Energy and Water Cycle Experiment-Surface Radiation Budget)、CERES-EBAF(Clouds and Earth’s Radiant Energy Systems-Energy Balanced and Filled)和GLASS-DSR(Global LAnd Surface Satellite-Downward Shortwave Radiation)3种辐射产品,以相关系数、平均偏差、均方根误差为评价指标在整个中国区域范围内进行精度评价,并且对其精度的时空分布特征进行了研究。研究表明,2000~2007年GEWEX-SRB与CERES-EBAF相比两者具有相似的偏差趋势,低估和高估最严重站点同为峨眉山站和太原站,总体上CERES-EBAF的精度更高。2008~2010年间GLASS-DSR与CERES-EBAF进行对比结果表明CERESEBAF精度要高。总体来说,这3种辐射产品的精度都较高,低估的站点大多地处高海拔地区,其中CERES-EBAF产品时间序列长且精度相对较高,尤其是在中东部及大部分沿海地区精度较高。
文摘1 引言 国际科学理事会与世界气象组织和其它一些国际组织共同发起组织的大型科学计划——“全球能量与水循环试验(Global Energy and Water cycle EXperiment简称:GEWEX)”是本世纪末世界气候研究计划中的一个主要计划,是为研究气候异常,进行长期预报和防灾减灾,保证粮食生产为目的而设立的世界性研究计划。该项始于1989年,预计到2005年完成的计划,在全球范围内共确定了德国波罗的海、美国密西西比河、亚洲、非洲和南美亚马逊河5大试验区,亚洲季风试验(GEWEX Asian Monsoon Experiment简称:GAME)计划是其中之一。
基金Supported by the Special Strategic Project of Leading Science and Technology of Chinese Academy of Sciences(XDA20100304)National Natural Science Foundation of China(41790471)。
文摘In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment(WCRP/GEWEX/GAME/HUBEX: World Climate Research Program/Global Energy and Water Cycle Experiment/Asian Monsoon Experiment/Huaihe River Basin Energy and Water Cycle Experiment) in the Huaihe River basin, Anhui Province of China. The main objective of this field experiment(HUBEX)was to investigate the multiple-scale structure characteristics, life cycles, and genesis and development mechanisms of the Meiyu system in East Asia as well as the cause of related flooding disasters. It was a joint China-Japan cooperative meteorological and hydrological observation experiment. On the basis of intensive observations, scientists from the two countries conducted follow-up investigations through collating and compiling data and performing scientific analysis during the following five years. It can be concluded that the HUBEX project has yielded comprehensive and remarkable achievements. This paper introduces the major scientific results derived from this field experiment and the ensuing investigations, and reassesses their merits and shortages for the purpose of providing useful experience and proposing new research targets as well as prospects for the initiation of a new joint scientific Meiyu experiment in the middle and lower Yangtze River basin.
