Anomalies of Ocean and General Atmospheric Circulation in 2008 and Their Impacts on Climate Anomalies in China
Although overall in 2008, there are not serious persistent drought and flood d isasters happened over countrywide due to the week anomalies of climate, some si gnificant anomalies of synoptic and climatic features occurred in China such as annual mean precipitation is above normal and ranked first among recent 10 years ,significant wet in South China and wet again in Huanghuai region during summe r, annual mean temperature is above normal while cold in winter with rare snow s torm and icefreeze disasters in south part of China in the beginning of the y ear,significant less than normal of typhoon generated over South China Sea and West Pacific. However， more than normal of typhoon landing China, as well as firs t naming typhoon occurred very early than normal. It is shown by diagnostic anal y sis that belownormal Sea Surface Temperature Anomalies (SSTa) are observed ove r the central and eastern Pacific in 2008 followed a cold phase of ENSO occurred in summer of 2007. Due to influence forced by SSTa and interaction between ocea n and atmosphere, general circulation over the Northern Hemisphere shown the do minant anomalies which have been characterized as respond as follows: the inten sity and position of subtropical high over the West Pacific varied frequently th an normal; East Asian monsoon was more strong than normal both in winter and sum mer; the tropical convective activities in warm pool of West Pacific were more a ctive from winter to spring and week from summer to fall of 2008 than normal; th e meridional circulation develop strongly in January and the zonal circulation develop strongly instead from February to April over midhigh latitude area of Asia, and the transition between meridional and zonal circulation was carried ou t frequently from latter spring to fall indicated the week persistence of circul ation. These may be the main factors that influence climate anomalies in China i n 2008.