摘要
利用中国675个气象观测站1955-2000年能见度观测资料,采用年季月平均和最小二乘法,分析了中国能见度变化趋势,初步探讨了中国大气环境的变化特征.用Ridit、累积百分率和"非常好"能见度出现频率分析法分别对六个城市1955-2000年的大气能见度进行分析,结果表明:1955-1964年能见度变化呈上升趋势,1965-1979年呈下降趋势,1980-2000年变化趋于平缓.中国能见度有较明显的季节和月变化特征,夏季能见度最好,秋季次之,冬季最差;一年之中7月份能见度最好,1月份最差.能见度低值区主要出现在新疆南部,四川、重庆及贵州交界处,湖南中部,河北和山西交界处,陕西南部以及黑龙江北部地区;高值区主要出现在新疆北部,四川西部.高值区对应上升趋势,低值区对应下降趋势,西部地区能见度比东部地区高.能见度与相对湿度呈较好的负相关,大气污染是能见度降低的重要因子.不同城市之间的能见度变化有显著差异.
Atmospheric visibility is one of the available indicators of atmospheric pollution. In order to well understand the course of atmospheric environment in China, the temporal variations of visibility were examined by using the annual and seasonal average and the Least Squares Method, based on the historical visibility data obtained from 675 meteorological stations from 1955 to 2000. The visibility trends in 6 cities from 1955 to 2000 were analyzed using the methods of Ridit analysis, cumulative percentiles and frequency of ＇very good＇ visibility. The results indicate that the visibility showed an increasing trend during 1955-1964, and then decreased in 1965-1979; during 1980-2000 the variation of visibility became moderate. Visibility in China possessed more significant seasonal and monthly characteristics. The best was in summer, especially in July. In winter, especially in January, it was the worst. The low visibility areas were mainly in southern Xinjiang, Sichuan and Chongqing, Guizhou, the central part of Hunan, the junction of Hebei and Shanxi, southern Shaanxi and northern Heilongjiang. The high value areas were in the northern part of Xinjiang and western Sichuan. The visibility in the eastern China was lower than western China. There was a good negative correlation between visibility and relative humidity. Atmosphere pollution was an important factor for visibility reduction. Different cities showed different characteristics in visibility variation.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2011年第6期46-55,共10页
Journal of Lanzhou University(Natural Sciences)
基金
国家重点基础研究发展规划项目(2011CB952003)
国家自然科学基金项目(40975092)
云南省自然科学基金项目(2009CD021)
云南省中青年学术和技术带头人后备人才培养计划项目(2009CI046)
