报告题目: Role of Anthropogenic Forcing in the Extreme High Temperature Events in China

　　报 告 人: Prof. Ying SUN

　　单 位: National Climate Center, China Meteorological Administration

　　时 间：2016年7月19日上午10:00

　　地 点：大气所40号楼319会议室

　　欢迎大家踊跃参加和讨论！

Abstract

The attributions of two extreme high temperature events in china were conducted based on single- and two-step attribution methods, respectively.

The spring of 2014 was the third warmest spring in Northern China since reliable observations were established in the late 1950s. We used a two-step attribution method to investigate the relative contribution from natural and human caused forcings to this event. The relation between mean temperature and high temperature evens are first built in the region. Then the detection of mean temperature were conducted based on the fingerprinting method. The results show that the anthropogenic forcing may have contributed to an 11-fold increased in the chance of the 2014 spring extreme high temperature event in Northern China.

The 2015 summer was very hot in Western China with new records for the daily maximum temperature in many stations in the region. The regional average of annual maxima of daily maximum (TXx) and daily minimum temperatures (TNx) reached their historical highs. It is interesting to find that anthropogenic influence can be directly detected in the extreme indices themselves at such a small regional scale. So the human influence can be estimated directly on the output of the optimal detection results. The preliminary results show that anthropogenic forcing may increase the occurrence of such events by at least 3-fold for TXx and 42-fold for TNx.