河西走廊东部近50年高、低温气候特征分析

Analysis on the Climatic Characteristics of High and Low Temperature in the East of Hexi Corridor in Recent 50 Years

[目的]分析河西走廊东部近50年高、低温气候特征。[方法]利用河西走廊东部5个气象站1960～2009年高(日最高气温≥35℃)、低温(日最低气温≤-20℃)资料,运用统计学方法详细分析了高、低气温的时空分布、强度、持续性和环流形势等气候特征。[结果]河西走廊东部高温天气主要发生在东北部沙漠边缘;低温天气主要发生在海拔较高的山区和北部沙漠边缘。随着气候变暖,高温日数呈弱增加趋势,强度增强;低温日数呈明显减少趋势,强度减弱。高温天气主要出现在7、8月;低温主要出现在1、2、12月。高、低温天气具有持续性特征,强高、低温大多出现在高、低温持续时段内。高温天气出现在副热带高压控制及影响的区域内;低温天气出现在强冷空气堆积和入侵的区域内。[结论]该研究为高、低温的准确预报和预警提供了一定的理论基础。

[Objective] The research aimed to analyze the climatic characteristics of high and low temperature in the east of Hexi Corridor in recent 50 years.[Method] Based on the high（the daily highest temperature ≥35 ℃） and low（the daily lowest temperature ≤-20 ℃） temperature data in five observatories in the east of Hexi Corridor during 1960-2009,the temporal and spatial distribution,intensity,continuity and circulation situation of high and low temperature were analyzed in detail by using the statistical method.[Result] The high temperature in the east of Hexi Corridor mainly happened in the edge of northeast desert,and the low temperature mainly happened in the mountain zone where the altitude was high and the edge of north desert.As the climate became warm,the high temperature days showed the weak increase trend,and the intensity strengthened.The low temperature days showed the obvious decrease trend,and the intensity weakened.The high temperature weather mainly occurred in June,August,and the low temperature mainly occurred in January,February,December.The high and low temperature weather had the durative characteristic.The strong high and low temperature mainly occurred in the durative time of high and low temperature.The high temperature weather appeared in the zone where was controlled and affected by the subtropical high.The low temperature weather appeared in the zone where the strong cold air accumulated and invaded.[Conclusion] The research provided the certain theory basis for the accurate forecast and early warning of high and low temperature.