欧亚遥相关与中国北方冬季雾霾的关系

The Relationship between Eurasian Teleconnection and Haze-Fog in Northern China in Winter

摘要: 本文利用36年气象观测资料和NCEP/NCAR再分析资料，采用多种统计学方法，研究分析了冬季大气环流形势与中国北方地区雾霾年际变化的关系。结果表明，500 hPa等压面上欧亚遥相关是影响中国北方雾霾的重要形势，新定义的欧亚遥相关指数与雾霾日数呈显著的负相关关系。欧亚遥相关处于负位相时，东亚大槽减弱，西风带在东亚表现为纬向环流，西伯利亚高压减弱，北风减弱，使得中国北方地区雾霾日数增多。反之，欧亚遥相关正位相时，雾霾日数减少。欧亚遥相关具有约13~15天发展和衰退的活动周期，在欧亚遥相关指数出现峰值前约两天，能见度开始显著变化，持续时间约5~6天。

Abstract: Using meteorological observation data and NCEP/NCAR reanalysis data, the impacts of the atmospheric circulation pattern on the interannual variability of haze-fog in northern China in winter are studied by means of statistical methods. The results show that the Eurasian telecon-nection at the 500 hPa isostatic surface is the most important pattern affecting the haze-fog frequency in northern China. There is a significant negative correlation between the newly defined Eurasian teleconnection index and the number of haze-fog days. When the Eurasian teleconnection is in a negative phase, the East Asia major trough weakens, the westerlies appear as a zonal circulation in East Asia, the Siberian high pressure and the northerly wind weakens. As a result, the occurrence of haze-fog in northern China has increased. When the Eurasian teleconnection is in the positive phase, the opposite is true. The EU pattern goes through a considerable development and decay within 13~15 days. The visibility starts to significantly change from lag −2 days of EU peak phase, and the duration is about 5~6 days.