北半球高纬地区年际尺度循环过程中的气-海-冰相互作用关系  

NUMERICALLY SIMULATED ATMOSPHERE-OCEAN-SEA ICE INTERACTION IN INTERANNUAL SCALE CYCLES IN HIGH NORTHERN LATITUDES

作　　者：刘喜迎[1] 刘海龙[2] 李薇[2] 张学洪[2] 宇如聪[3] 俞永强[2] 

机构地区：[1]解放军理工大学气象学院军事气象系,南京211101 [2]中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室,北京100029 [3]中国气象局,北京100081

出　　处：《气象学报》2007年第3期384-392,共9页Acta Meteorologica Sinica

基　　金：国家重点基础研究专项经费项目(2005CB32170X);国家自然科学基金项目(40675065)

摘　　要：基于一个全球气-海-冰耦合模式数值模拟结果,对北半球高纬度地区年际尺度的气-海-冰相互作用进行了分析。在所使用的全球气-海-冰耦合模式中,大气环流模式和陆面过程模式来自国家气候中心,海洋环流模式和海冰模式来自中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室。采用一种逐日通量距平耦合方案实现次网格尺度海冰非均匀条件下大气环流模式和海洋环流模式在高纬地区的耦合。只对50 a模拟结果中的后30 a结果进行了分析。在分析中,首先对滤波后的北半球高纬度地区海平面气压、表面大气温度、海表面温度、海冰密集度及海表面感热通量的标准化距平做联合复经验正交函数分解,取第一模进行重建,然后讨论了在一个循环周期(约4 a)中北半球高纬度地区气-海-冰的作用关系。结果表明:(1)当北大西洋涛动处于正位相时,格陵兰海出现南风异常,使表面大气温度升高,海洋失去感热通量减少,海洋表面温度升高,海冰密集度减小;当北大西洋涛动处于负位相时,格陵兰海出现北风异常,使表面大气温度降低,海洋失去感热通量增多,海洋表面温度降低,海冰密集度增加。巴伦支海变化特点与格陵兰海相似,但在时间上并不完全一致。(2)多年平均而言,北冰洋内部靠近极点区域为冷中心。当北冰洋内部为低压异常时,因异常中心偏向太平洋一侧,使北冰洋内部靠近太平洋部分为暖平流异常,靠近大西洋一侧为冷平流异常。伴随着暖、冷平流异常,这两侧分别出现暖异常和冷异常,海表面给大气的感热通量分别偏少和偏多,上述海区海表面温度分别偏高和偏低,海冰密集度分别偏小和偏大。当北冰洋内部为高压异常时特点正好与上述相反。由上述分析结果可知,在海洋、大气年际循环中,大尺度大气环流变率起主导作用,海洋表面温�The interannual atmosphere-ocean-sea ice interaction in high northern latitudes is studied with a global atmosphere-ocean-sea ice coupled model system, in which the model components of atmosphere and land surface are from National Climate Center of China and that of ocean and sea ice from LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences. A daily flux anomaly correction scheme was employed to couple the atmosphere model and the ocean model with the effect of inhomogenity of sea ice in high latitudes considered. The coupled model system has been run for 50 years and results of the last 30 years were analyzed. After the sea surface temperature（SST）, sea ice concentration （SIC）, sea level pressure （SLP）, sea surface sensible heat flux （SHF） and surface air temperature（SAT） were filtered with a digital filter firstly, their normalized anomalies were used in the decomposition of combined complex empirical orthogonal function and then the anomalies were reconstructed with the leading modes. At last, air-ocean-sea ice interactions in high northern latitudes during a periodical cycle （approximately 4 years） were analyzed. It＇s shown that when the North Atlantic Oscillation （NAO） is in its positive phase, the southerly wind anomaly appears in Greenland Sea, the SAT increases, the sea losses less sensible heat, the SST increases and the SIC decreases accordingly; when the NAO is in its negative phase, the northerly wind anomaly appears in Greenland Sea, the SAT decreases, the sea losses more sensible heat, the SST decreases and the SIC increases accordingly. There are similar evolutional features in Barents Sea, but the phase of evolution in Barents Sea is different from that in Greenland Sea. For an average of multiyears, there is a cold centre in the inner part of Arctic Ocean close to the North Pole, which is closer to the Pacific Ocean side when there is an low pressure anomaly in the inner part, the anomalous warm advection of sea water appears in the region closer to th

关 键 词：耦合模式 气-海-冰相互作用 联合复经验正交函数分解 

分 类 号：P731.15[天文地球—海洋科学]