新疆棉花障碍型冷害的天气成因  

Study on Weather Causes for Severe Cold Disasters on Cotton Plants in Xinjiang

作　　者：杨莲梅[1] 李新建[1] 

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所

出　　处：《干旱区研究》2006年第4期609-614,共6页Arid Zone Research

基　　金：科技部基础性研究项目"新疆棉区棉花冷害的预测预报研究";国家自然科学基金项目(30170535);科技部重大基础研究前期研究专项(2002cca04600)共同资助

摘　　要：应用乌苏、炮台和石河子3个气象站1961-2003年7月10日-8月15日的逐日气象观测资料和现有的棉花生长发育观测资料,选出棉区最严重的3次障碍型冷害过程,分析冷害天气前期、过程中的光、热、水和风速气象要素的特点和天气成因。结果表明：①产生障碍型冷害天气过程是持续3d以上的日平均气温低于20．0℃的强降温天气,连续的阴雨、无日照加重冷害的影响,即阴冷湿型危害重于冷干型。②盛夏持续性低温过程的大气环流背景是100hPa南亚高压北侧的副热带锋区上的低槽,南亚高压双体型导致副热带槽偏南(40°N以南)造成阴冷湿型冷害,单体型导致副热带槽偏北(40°N以北)造成冷干型冷害。③500hPa中纬地区为经向环流,伊朗高压脊强烈向北发展导致北方冷空气南下,在中亚形成深厚稳定的冷性低涡,该低涡冷空气低于-20．0℃,从而造成持续性低温过程,低涡偏南(40°N以南)降水较大造成阴冷湿型冷害,低涡偏北(40°N以北)降水较小且不连续造成冷干型冷害。In this paper, the meteorological factors, such as the sunshine duration, heat regime, precipitation and wind speed, and the weather causes for three severe cold die.asters on cotton plants in Xinjiang are analyzed based on the daily data observed in Shihezi, Usu and Paotai meteorological stations from July 10 to August 15 during the period of 1962 - 2003. The results are as follows： （ 1 ） The occurrence of severe cold disasters is caused by sharp temperature decrease in more than three continuous days with an average daily temperature below 20.0℃, and the durative overcast and rainy days without sunshine can enhance the severe cold disasters. The overcast-cold-humid cold disasters are more serious than the cold-dry cold disasters; （2） The atmospheric circulation background of durative low temperature process in midsummer is the trough of subtropical front of South Asian high at 100 hPa. Double centers of South Asian high bring about the subtropical trough to be on the south side （south from 40°N） and result in cold-humid cold disasters, whereas a single center of South Asian high brings about the subtropical trough to be on the north side （north from 40°N） and results in cold-dry cold disasters; （3） At 500 hPa, there is a meridional circulation over the mid-latitude regions, the strong northward development of Iran wedge makes cold air move southward, thus a deep and stable cold whorl with temperature below - 20.0℃ forms over Central Asia, and a continuous low temperature process occurs. If the whorl is on the south side （south from 40°N）, a cold-wet cold disaster will occur; if the whorl is on the north side （north from 40°N）, a coid-dry cold disaster will occur.

关 键 词：棉花 障碍型冷害 气象要素 大气环流 新疆 

分 类 号：S42[农业科学—植物保护]