摘要
利用临安本底站酸雨长期观测资料,分析了该站酸雨年际变化及月变化,并对其变化特征进行了归因,同时分析了酸雨与气象因子之间的关系.结果表明,1985~2012年期间,临安本底站的酸雨总体呈增加趋势,且有2次明显加重和2次明显减弱过程.近20年酸雨的月变化表现为以7月为中心月份,降水酸度及强酸雨发生频率向两侧月份增加,弱酸雨发生频率向两侧月份减小.酸雨发生受降水强度、风速、风向影响,小雨时强酸雨发生频率高、弱酸雨发生频率低,而暴雨时弱酸雨发生频率高、强酸雨发生频率低;随风速等级升高,酸雨发生频率及强酸雨所占比重逐渐降低,降水pH值逐渐升高;弱酸雨发生日主导风向多集中于S-W扇区,而强酸雨发生日主导风向更倾向于N-E扇区.临安本底站酸雨的月变化主要归因于降水量变化以及各月SSE-WSW和NWN-ENE风向扇区来风的增多和减少,酸雨的年际变化可归因于江浙沪能源消耗量增加及重大环保措施实行的综合影响.
Using long-term observation data of acid rain at Lin＇an Regional Background Station （ Lin＇an RBS） , this paper studied the interannual and monthly variations of acid rain, the reasons for the variations, and the relationships between acid rain and meteorological factors. The results showed that interannual variation of acid rain at Lin＇an RBS had a general increasing trend in which there were two obvious intensifying processes and two distinct weakening processes, during the period ranging from 1985 to 2012. In last two decades, the monthly variation of acid rain at Lin＇an RBS indicated that rain acidity and frequency of severe acid rain were increasing but the frequency of weak acid rain was decreasing when moving towards bilateral side months of July. Acid rain occurrence was affected by rainfall intensity, wind speed and wind direction. High frequency of severe acid rain and low frequency of weak acid rain were on days with drizzle, but high frequency of weak acid rain and low frequency of severe acid rain occurred on rainstorm days. With wind speed upgrading, the frequency of acid rain and the proportion of severe acid rain were declining, the pH value of precipitation was reducing too. Another character is that daily dominant wind direction of weak acid rain majorly converged in S-W section,however that of severe acid rain was more likely distributed in N-E section. The monthly variation of acid rain at Lin＇an RBS was mainly attributed to precipitation variation, the increasing and decreasing of monthly incoming wind from SSE-WSW and NWN- ENE sections of wind direction. The interannual variation of acid rain could be due to the effects of energy consumption raising and significant green policies conducted in Zheiian~, Jian^su and Shanghai.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2014年第2期481-489,共9页
Environmental Science
基金
国家自然科学基金重点项目(90815028)
公益性行业(气象)科研专项(GYHY201306050)
关键词
酸雨
长序列
PH值
年际变化
临安本底站
acid rain
long-time series
pH value
interannual variation
Lin＇an regional background station
