北极水汽输送的时空分布特征研究  

Temporal and spatial distributions of water vapor transport in the Arctic

作　　者：温世强 常亮[1,2,3] Wen Shiqiang;Chang Liang(College of Marine Sciences,Shanghai Ocean University,Shanghai 201306,China;State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China;Key Laboratory for Polar Science,MNR,Polar Research Institute of China,Shanghai 200136,China)

机构地区：[1]上海海洋大学,海洋科学学院,上海201306 [2]自然资源部第二海洋研究所,卫星海洋动力学国家重点实验室,浙江杭州310012 [3]中国极地研究中心,自然资源部极地科学重点实验室,上海200136

出　　处：《极地研究》2022年第3期265-277,共13页Chinese Journal of Polar Research

基　　金：国家自然科学基金(42174016,42076240);上海市浦江人才计划(19PJ1404300);自然资源部极地科学重点实验室开放研究基金(KP201701);自然资源部卫星海洋环境动力学国家重点实验室开放研究基金(QNHX2122)资助。

摘　　要：水汽输送可以通过直接或间接的方式影响北极地区(60°N—90°N)的水文、辐射和动力等气候因子。了解水汽输送的分布和变化特征,对研究北极气候变化具有重要意义。本文基于ERA5、JRA-55和MERRA-2再分析资料,分析了1980—2018年沿70°N水汽通量的水平分布、垂直分布和月平均分布,以及北极地区整层水汽通量在不同季节的变化特征和线性趋势。基于三种再分析资料的分析结果均表明,沿70°N的水汽输送在东北极主要为向北,在西北极为向南和向北相间分布且相对于东北极更活跃;沿70°N的向北水汽输送在垂直方向上的900hPa高度附近较为强烈。此外,沿70°N的向北水汽输送通量平均高于向南,说明了北极地区整体体现为水汽汇入地。北极地区的向北水汽输送在夏秋季比冬春季节更活跃,且夏秋季的水汽通量在向北水汽输送通道附近和北大西洋区域的增速更为明显。对沿70°N的水汽入侵的时间变化和水平分布结果进行分析后发现,水汽入侵主要发生在向北水汽输送通道附近,且水汽入侵受比湿的影响比经向风更大,这使得水汽入侵的年平均次数在2008年之后出现剧烈波动。整体上,相比ERA5和JRA-55,MERRA-2与IGRA2的正相关性更强且精度更高,更适用于北极水汽输送研究。In the Arctic(60°N–90°N),water vapor transport directly and indirectly affects aspects of the climate system,including the radiation balance and the dynamics of the hydrological cycle.Understanding the distribution and variations of water vapor transport is important for the study of Arctic climate change.Using ERA5,JRA-55,and MERRA-2 reanalysis data from 1980 to 2018,we analyzed the horizontal and vertical distributions and the monthly and seasonal variations of water vapor flux at 70°N.Our results show that the direction of water vapor transport at 70°N is affected by the distribution of land and sea.Water vapor transport is northward in the eastern Arctic,and alternates between southward and northward in the western Arctic.Water vapor transport in the eastern Arctic is higher than that in the western Arctic.The northward water vapor transport is the highest near the 900-hPa level.At 70°N,the average northward water vapor transport is higher than the average southward water vapor transport.As a result,water vapor accumulates in the Arctic region.The northward water vapor transport is more active in the summer and autumn than in the winter and spring.The water vapor flux increases rapidly near the northward water vapor transport channel and in the North Atlantic region in the summer and autumn.Variations in the temporal and horizontal distributions of water vapor intrusion at 70°N indicate that intrusion mainly occurs near the northward water vapor transport channel,and is more strongly affected by specific humidity than by meridional wind.As a result,there were large fluctuations in the annual average number of water vapor intrusions after 2008.We computed the correlation coefficients between the IGRA2 observation dataset and each of the three reanalysis datasets.The correlation coefficient between IGRA2 and MERRA-2 is positive and is larger than the coefficient between IGRA2 and ERA5 and the coefficient between IGRA2 and JRA-55.Accuracy of MERRA-2 is also higher than that of ERA5 and JRA-55.We conclude

关 键 词：北极 再分析资料 水汽输送 时空分布 

分 类 号：P941.62[天文地球—自然地理学] P426