1961~2000年中国区域气温较差分析

利用1961~2000年的观测资料，分别对中国不同区域的月、季和年平均气温日较差，以及月较差、季较差和年较差的变化趋势进行了分析。研究表明，月平均日较差以及季平均日较差均有显著的下降趋势，其中春夏两季的变化趋势最为明显，冬季次之，秋季下降趋势最弱；年平均日较差也显示了较强的下降趋势。月较差显著减小趋势主要发生在冬末和春季；季较差以夏季的变化最显著，其他几个季节都没有明显的下降趋势；但是年较差有很显著的减小。从地域上看，月、季和年平均日较差以东北和新疆的下降趋势最显著，最弱的是华北地区。总体上看，月、季平均日较差北方较南方的下降趋势明显。月较差的减小趋势在北方比南方显著；季较差的下降趋势主要表现在夏季，又以内蒙古到西南一带以及华北地区最显著；年较差东部比西部的下降趋势显著。

Analysis of Temperature Range from 1961 through 2000 across China

Based on China's daily temperature data during 1961-2000, we analysed monthly averaged diurnal temperature range, seasonally averaged diurnal temperature range, yearly averaged diurnal temperature range, monthly temperature range, seasonal temperature range and annual temperature range in different areas of China. The results show that the decreasing trends of monthly averaged diurnal temperature range and seasonally averaged diurnal temperature range in most parts of China in spring and summer are greater than those in other seasons, and weaker in autumn than in other seasons. The yearly averaged temperature range also displays significant declining trends in most parts of China. While the decreasing trends of monthly temperature range are greater at the end of winter and spring than those in other seasons and the decreasing trends of seasonal temperature range are greatest in summer, other seasons have not evident decreasing trends. Yearly temperature range also displays evident decreasing trends in China. There exists an obvious regional difference in trends of them in China. The decreasing trends of monthly averaged diurnal temperature range, seasonally averaged diurnal temperature range and yearly averaged diurnal temperature range are obvious in Northeast China and Xinjiang Uygur Autonomous Region, and lower than in other areas of southern North China. As a whole, the decreasing trends of monthly averaged diurnal temperature range and seasonally averaged diurnal temperature range are more obvious in North China than in the South. And the decreasing trends of monthly temperature range are more obvious in North China than in the South. The decreasing trends of seasonal temperature range are obvious in those regions lying from Inner Mongolia to Southwest China and the southern part of North China in summer. The decreasing trends of annual temperature range are more obvious in East China than in the West.