贵阳地区太阳紫外辐射变化特征及主要影响因子分析

Characteristics and Impact Factors of Ultraviolet Radiation in Guiyang

利用贵阳地区近6年太阳紫外辐射的观测资料及相关的气象因子,分析了该地区太阳紫外辐射的变化特征。结果表明,贵阳地区紫外辐射逐时平均最大值为21W.m-2(四级强度),瞬时最大值为26.4W.m-2,未出现很强辐射(五级)的情况;4～9月出现强紫外辐射的时段较长,在10:00～15:00可达四级;13:00强紫外辐射在4～9月出现的几率最大,尤其是7月和8月分别达到52%和51%;晴天紫外辐射强且稳定,多云天气紫外辐射波动较大,阴雨天气紫外辐射较弱;一年中,晴天和多云条件下,中午时刻各月紫外辐射量均超过了10W.m-2,而阴天的情况下仅在7～9月出现中等辐射,3种天气情况下的紫外辐射随季节的变化趋势相似,均表现为冬季弱、夏季强的特点;云量、相对湿度以及能见度与贵阳地区太阳紫外辐射具有显著的相关性。

Based on the observation data of Guiyang in recent 6 years,the change characteristic of ultraviolet（UV） radiation is analyzed. The results showed that the maximum of hourly averageUV radiation is 21 W·m-2（four-grade intensity）,and the instantaneous maximum is 26.4 W·m-2,strong UV radiation in 5 grade does not appear.Strong UV radiation period is long fromApril to September,and it can reaches 4 gradesat 10：00～15：00;Strong UVradiation at 13：00 occurrs most probably from April to September,especially in July and August,it reaches 52% and 51%,respectively.UVradiation is strong and stable in sunnyday,fluctuates obviously incloudy day and weak in rainy day;Monthly UV radiation at noon exceed10W·m-2under sunny and cloudy conditions,while only medium intensityappears from July to September under overcast condition;seasonalvariation trends under three weather conditions are similar,they are all weak in winter and strong in summer.Cloudiness,relative humidityand visibility have significant correlation tothe UV radiation in Guiyang.