关键词: OLR, 气温, EOF 分析, 青藏高原, 中国西北, 干旱区

Abstract:

 Based on temperature data of 82 stations in Northwest China and NCEP reanalysis data of the monthly mean grid OLR，the relationship between air temperature in Arid region of Northwest China and OLR over the Qinghai － Tibet plateau was analyzed by using EOF，synthesis and correlation analysis methods． The main conclusions are as follows: ( 1) The high value center of the first mode of OLR concentrated in the northern Tibet Plateau，which faced west in winter and moved to the east in spring，in summer located in west section of the Tanghla mountain． The temperature in January correlated positively with OLR at the same time，and they had the same decadal and interannual change tendency，but presented opposite correlation with the OLR lagged for six months ( July of last year) ．The temperature in July and the same time OLR presented opposite decadal tendency，but the opposite interannual trend was not remarkable，and correlated positively with the OLR lagged for seven months ( December of last year) and negatively with OLR lagged for11 months ( August of last year) ． Namely，when the OLR over Qinghai － Tibet plain in July was abnormally large ( small) ，the temperature in January of next year in arid region was abnormally low ( high) ． When OLR over Qinghai － Tibet Plain in August and December
was abnormally large ( small) ，the temperature in July of next year would be abnormally high ( low) ; ( 2) The low value center of OLR over Qinghai － Tibet plateau also has some relations with temperature in arid region of Northwest China，namely，the temperature in January correlated positively with OLR at the same time and negatively with OLR lagged for 17 months，the temperature in July correlated positively with OLR lagged for 17 months and negatively with OLR lagged for 12 months．

Key words: OLR, EOF, air temperature, Qinghai － Tibet Plateau, Northwest China, arid area