摘要:基于我国地区543个地面气象台站观测的总云量、平均气温和相对湿度日均值资料，采用正交经验函数（EOF）、气候倾向率和线性趋势分析等方法，研究了1960~2012年总云量的时空变化特征及其与气温和水汽的关系。结果表明：（1）我国地区总云量呈南多北少的带状分布特征，最大值在四川盆地（82%）。近53年来总云量气候倾向率为-0.8%（10a）-1，趋势系数为-0.68，通过了99.9%的信度检验。（2）总云量季节变化特点明显，夏季最多，春秋季次之，冬季最少，其中春季、夏季和秋季有显著的下降趋势。（3）EOF分解的前两个模态表明总云量不仅具有一致减少的变化特征，还具有明显的区域差异。以此同时，平均气温和相对湿度不论在总体变化趋势、地区差异、还是时间演变上，均与总云量保持较高的一致性，进一步证明总云量的变化与气温和水汽有密切关系。
关键词:总云量/
平均气温/
相对湿度/
影响因子
Abstract:This study investigates temporal and spatial variations of total cloud cover (TCC) in China during 1960 to 2012 and further analyzes their relationships with temperature and relative humidity based on the dataset of observations from 543 surface meteorological stations in China. Basic statistical methods, including the empirical orthogonal function (EOF) and climate tendency and linear trend analysis, are used here. It is found that TCC is higher in South China than in North China with the maximum value occurring in Sichuan Basin (82%). The climate tendency of TCC in China is -0.8%(10a)-1 in the recent 53 years and the trend coefficient is -0.68. The variation of the TCC in China demonstrates remarkable seasonal change, which is the largest in the summer and smallest in the winter. It exhibits a clear declining trend in all seasons except the winter. In addition, the first two dominant EOF modes of TCC display a uniform declining variation and apparent regional differences. Meanwhile, variations of temperature and relative humidity are consistent with the variations of TCC with respect to the trend, regional differences and temporal evolution, implying a close relationship between the variations of TCC and these two variables.
Key words:Total cloud amount/
Average temperature/
Relative humidity/
Impact factor
PDF全文下载地址:
http://www.iapjournals.ac.cn/dqkx/article/exportPdf?id=20190107
