中国北方农牧交错带春季风速的年际变化与冬季海温的关系  

Relationships between interannual variations of spring winds in the agro-pastoral transitional zone of Northern China and winter sea surface temperature

作　　者：胡毅鸿 龚道溢[1,2,3] 毛睿 石晓雪[1,2,3] HU Yihong;GONG Daoyi;MAO Rui;SHI Xiaoxue(Key Laboratory of Environmental Change and Natural Disaster,Ministry of Education,Beijing Normal University,Beijing 100875,China;Academy of Disaster Reduction and Emergency Management,Beijing Normal University,Beijing 100875,China;Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China)

机构地区：[1]北京师范大学环境演变与自然灾害教育部重点实验室,北京100875 [2]北京师范大学减灾与应急管理研究院,北京100875 [3]北京师范大学地理科学学部,北京100875

出　　处：《地理科学进展》2019年第5期709-717,共9页Progress in Geography

基　　金：国家自然科学基金项目(41621061);国家重点研发计划项目(2016YFA0602401)~~

摘　　要：利用中国北方农牧交错带1979-2016年64个气象台站的逐日风速资料、ERSST海温数据以及ERA-Interim再分析资料,探讨了前期冬季海温与北方农牧交错带春季风速年际变化的关系。研究表明,北方农牧交错带春季的风速存在强烈的逐年波动,年际方差占总方差的比例为36%。影响农牧交错带春季风速年际变化的前期冬季海温在北大西洋20°N^65°N区域呈现"负、正、负"的异常分布,在北太平洋10°N^55°N、130°W^180°区域呈现"负、正"的异常分布。冬季的海温异常与研究区春季风速年际变化联系的桥梁是北半球大尺度大气环流的异常。当北大西洋海温从高纬至低纬呈现"负、正、负"的异常分布时,从北大西洋至东亚位势高度呈明显的"正、负、正、负"的波列特征;当北太平洋海温从高纬至低纬呈现"负、正"的异常分布时,从北太平洋至东亚位势高度呈"负、正、负、正、负、正"的三波型分布。二者均能影响东亚地区春季大气环流的变化,导致东亚地区上空产生一个异常的气旋性环流,该气旋性环流在对流层中层与低层均存在,是造成研究区风速变化的直接原因。冬季海温与研究区春季风速的显著相关,说明冬季海温对农牧交错带春季风速的年际变化具有超前指示意义。利用北大西洋和北太平洋海温异常中心区的冬季海温作为预报因子,建立春季风速预报模型,可以解释风速年际变化的32%,回报交叉验证结果表明,海温与风速的时间滞后关系是显著和稳健的。This study investigated possible relationships between winter sea surface temperature(SST) and the interannual variation of spring wind speed in the agro-pastoral transitional zone of Northern China by employing daily wind speed observations of 64 meteorological stations, the extended reconstructed sea surface temperature,version 5(ERSST v5) dataset, and the ERA-Interim reanalysis data. The results show that spring wind exhibited strong year-to-year variations. During the period of 1979-2016, the interannual components accounted for 36%of the total variance. Winter SST, which affects the interannual variation of wind speed in the study area in spring, presented a negative-positive-negative distribution between 20° N-65° N in the North Atlantic, and a negative-positive distribution in the domain of 10° N-55° N and 130° W-180° in the North Pacific Ocean.Interannual variations of surface spring wind in the study area were significantly related to the North Atlantic SST index(r = 0.50) and the North Pacific SST index(r = 0.44). The large-scale atmospheric circulation in the northern hemisphere is the bridge that links winter SSTs and the spring wind. In association with the North Atlantic SST anomalies of negative-positive-negative distribution from high to low latitudes, a wave pattern of pressure height anomalies appeared over the North Atlantic and Eurasia. Accompanying a negative-positive distribution in North Pacific SST anomalies, the pressure height anomalies from the North Pacific to East Asia presented a three-wave pattern. Both of them can lead to an anomalous cyclonic circulation over East Asia in spring. The anomalous cyclonic circulation existed in both the middle and the lower troposphere, which was the factor directly resulting in higher wind speed over the study area. The significant correlation between winter SST and spring wind speed implies that winter SST can be used as a skillful predictor for spring wind in practice. A statistical forecast model with winter SSTs in the North Atlantic and N

关 键 词：风速 海温 年际变化 北方农牧交错带 

分 类 号：P425[天文地球—大气科学及气象学] P731.11