摘要
建立在全国110站的日平均表面温度资料的基础上,着重分析了北方干旱和半干旱地区1951～2000年极端温度发生频率和强度的变化趋势,同时给出了年极端温度变化的变化趋势及区域差异;最后讨论了极端温度的时空特征和区域增暖的相互联系.结果指出:从1951到2000年,在北方干旱和半干旱地区,最低温度发生的频率显著减小,只是趋势开始的时间存在区域差异;与之不同的是,20世纪90年代以前,绝大多数地区最高温度发生的频率没有明显的变化趋势,但近10年却有一个明显的增加趋势;年极端日平均温度强度的分析结果表明:北方地区年最低温度存在显著的减小趋势.从各个分区零温度以下天数的统计结果来看,北方地区近50年来零温度的天数正在减少,且零温度的开始时间推后,结束时间提前.另外,通过分析北方地区极端温度发生的频率及年极端温度和区域增暖的关系发现,当前的增温趋势与极端最低温度发生频率的减少和年最低温度的升高密切相关,近10年极端最高温度的增加加剧了增温的幅度.
Based on daily mean surface temperature of 110 stations over China from 1951 to 2000, trends of days and intensity of extreme temperature over arid and semi-arid area of China have been analyzed, and the trend of annual extreme temperature and differences among regions were shown; also temporal and spatial characteristics of extreme temperature and its relationship to regional warming have been discussed finally. The results show that there is a remarkable decreasing trend of days of minimum temperature over arid and semi-arid areas during the period, and the beginning date of trend is different in different regions. Compared with the trend of minimum temperature, there is no obvious trend of maximum temperature days before the 1990s, but there is a remarkable increasing trend in maximum temperature days since 1990. Except days of extreme temperature, there is decrease trend of annual minimum temperature. The results have also shown the trend of zero temperature(under 0 o C), i.e., there is reduction trend of zero temperature days, and its beginning date delays, and ending date is earlier. In addition, we found that the regional warming in northern China is closely related to reduction of minimum temperature days, and increase of maximum temperature days has intensified regional warming since 1990.
出处
《地理学报》
EI
CSCD
北大核心
2003年第z1期11-20,共10页
Acta Geographica Sinica
基金
国家重点基础研究发展规划项目(G1999043405)
中国科学院知识创新工程重大项目(KZCX1-10-07) ~~
