中文摘要：

利用上海11个气象站点1960～2008年日均相对湿度、能见度以及天气现象资料，重建了上海近503霾气候数据序列，并从时间和空间两个方面分析了上海霾日数的气候特征和变化规律。结果表明，上海霾气候数据序列重建值与报表记录值之间变化形态存在着较好的一致性，重建值较记录值偏高。1960～2008年，上海霾日数以9．7d／10a的线性趋势显著增加，2002年以后霾日数总体上呈减少趋势。上海多年平均霾日数以冬季最多而夏季最少。近50a，上海霾日数呈现出西南部最多-市区较多-东北和东南部最少的空间分布，霾日数的空间变化趋势则表现为西南部增加较多而东部增加较少。1981～2008年，上海霾日数在西部和南部都增加，东部则减少。

英文摘要：

Haze is traditionally an atmospheric phenomenon where dust, smoke and other dry particles obscure the clarity of the sky,and it has important effects on the social economy and human health. Based on the daily average relative humidity,visibility and weather information of 11 Shanghai meteorological sites from 1960 to 2008,climate data series of haze days over the past 50 years in Shanghai were reconstructed and the spatial and temporal characteristics and change of the number of haze days was analyzed with the method of climate statistics. The results showed that reconstructed data of haze days was pretty consistent with the records from surface meteorological observation report forms, and the change of reconstructed data was more stable. From 1960 to 2008,the number of haze days in Shanghai was significantly increasing with a linear trend of 9.7 d/10 a,while after 2002,the number decreased overall. The average number from 1960 to 2008 was the maximum in winter and the minimum in summer. During the past 50 years, the spatial distribution of haze days was the most in the southwestern part,more in the urban areas and the least in the northeastern and southeastern parts of Shanghai, while the spatial trend of haze days was increased more in the southwestern part and less in the eastern part. During the period from 1981 to 2008 ,the number of haze days increased in both the western part and the southern parts, but decreased in the eastern part of Shanghai.