【摘要】 风寒温度是冬季表征人体热舒适度常用的参数,也是气候变化影响研究中关注的要素。本文利用中国地面国际交换站气候资料月值数据集的气温和风速,分析1956-2005年中国冬季风寒温度的时间和空间变化特征。结果表明,近50年来中国冬季风寒温度普遍呈上升趋势,全国平均升高3.2oC,变化速率达0.64oC/10a;西北、华北、东北和青藏地区的上升速率分别为0.79oC/10a、0.84oC/10a、0.81oC/10a、0.80oC/10a,其中华北北部农牧交错带地区上升趋势最为强烈,超过1oC/10a;35oN以南的我国南方地区上升速率较低,为0.39oC/10a。风寒温度的这种变化特征是近50年来气温升高和风速下降综合作用的结果。其中气温变化造成的风寒温度上升是2.4oC,而地表风速下降对风寒温度的贡献为0.8oC。东亚气温和风速的变化受诸多大气环流系统的影响,分析表明影响东亚气候的几个主要环流因子中,西伯利亚高压、北极涛动、西太平洋遥相关型和欧亚遥相关型等与风寒温度有显著相关。这四个环流因子一起能解释50年来全国平均风寒温度方差的46.7%。全国平均气温与这四个环流因子的相关分别达到-0.65,+0.49,+0.31和-0.32;而平均风速与北极涛动的相关最显著,达-0.51。更多还原

【Abstract】 Based on the data of temperature and wind speed for the meteorological observation stations in China,and according to the latest WCT formula,this paper analyzed the wind-chill temperature changes in winter over China during the past 50 years. The mean WCT in winter rises by 3.2 oC in the period,with a rate of about 0.64 oC/10a. The warming rates of Southwest China,North China,Southeast China and Tibetan Plateau are 0.79 oC/10a,0.84 oC/10a,0.81 oC/10a and 0.80 oC/10a respectively; Simultaneously,the decreasing trend of the WCT in southern China (< 35 oN) is significantly lower than in northern,0.39 oC/10a. The changes of WCT are the outcome of the combined effects of increasing temperature and decreasing wind speed. The fraction solely relates to the temperature. The wind speed is 2.4 oC and 0.8 oC in WCT,respectively. The results show that WCT might be affected by Siberian High,Arctic Oscillation,western Pacific teleconnection pattern and Eurasian pattern. The four circulation factors can explain the variance for mean winter WCT over China is 46.7%.更多还原