摘要
为详细了解京西生态涵养区日照情况,利用北京市门头沟、斋堂两个国家气象站1975–2019年逐日总云量、低云量、降水日数、相对湿度、日照时数等资料,采用气候倾向率、Mann-Kendall检验等方法分析了京西生态涵养区日照时数时空变化特征及其与各气象要素之间的相关性。结果表明:在1975–2019年间,京西生态涵养区年、月、日日照时数均呈西部山区多、东南平原少的特征,且两站日日照时数呈显著相关性,约80%的差值在-2~2 h范围。其中月均日照时数峰值出现在4–5月,谷值出现在11–12月, 6月、9–10月减少趋势最明显;四季日照时数分布较均匀,但呈春季多、冬季少的特征;2002–2010年年日照时数连续低于均值,东南平原区减少趋势[-51.6 h·(10a)^(-1)]大于西部山区[-39.5 h·(10a)^(-1)]。年、四季日照时数异常偏少情况主要出现在2000年以后,接近异常偏多年份在20世纪80–90年代较集中。1982–1990年日照时数明显增加, 1991年发生明显减少突变, 1991–2019年日照时数明显减少。综合分析表明该地区的日照时数与总云量、低云量、日平均湿度、日降水量呈负相关,与日分钟风速、能见度呈正相关,该结论对首都京西生态涵养区建设和气候评价具有重要参考价值。
To deeply understand the sunshine duration characteristics in the ecological conservation area of West Beijing(ECAWB), China, based on the data of daily total cloud cover, low cloud cover, precipitation days, relative humidity and daily sunshine duration of Mentougou and Zhaitang National Meteorological Stations in Beijing from1975 to 2019, the spatial and temporal variation of sunshine duration in ECAWB, as well as the correlations with the various meteorological elements, are analyzed by using climate tendency rate and Mann-Kendall test methods.The results show that from 1975 to 2019, the annual, monthly, and daily sunshine duration in ECAWB were long in western mountainous area and short in southeastern plains, with significant correlations in the daily sunshine duration between the two meteorological stations(with about 80% of the difference in the range of-2 h to 2 h). The peak of monthly average sunshine duration was observed in April and May, and the valley appeared in November and December, with a most significant decreasing trend observed in June, September and October. The seasonal distribution of sunshine duration was generally uniform, despite more sunshine duration observed in spring and less in winter. In the meantime, the annual sunshine duration during 2002–2010 were consistently below the mean value,with a greater decreasing trend observed in southeastern plains(-51.6 h·(10a)^(-1)) than in western mountainous area(-39.5 h·(10a)^(-1)). Anomalously higher annual and seasonal sunshine duration were mainly observed from1980s to 1990s, while anomalously lower annual and seasonal sunshine duration mainly occurred after 2000. The sunshine duration increased significantly during 1982–1990, and then decreased considerably from 1991 to 2019.The comprehensive analysis shows that the sunshine duration in this area were negatively correlated with total cloud cover, low cloud cover, daily average humidity, and daily precipitation, while significantly positively correlated with daily wind speed as well as visibility. These findings could be critical reference for the construction and climate evaluation in ECAWB.
作者
吴辉
曹久才
缪明榕
李超
WU Hui;CAO Jiucai;MIAO Mingrong;LI Chao(Meteorological Bureau of Mentougou District,Beijing,102300,China;Meteorological Bureau of Nantong City,Nantong 226000,China)
出处
《大气与环境光学学报》
CAS
CSCD
2022年第2期195-204,共10页
Journal of Atmospheric and Environmental Optics
基金
中国气象局自主研究项目,2020ZZXM01。
关键词
京西生态涵养区
日照时数
时空分布特征
相关关系
ecological conservation area of West Beijing
sunshine duration
spatial and temporal variation
correlations
