降水量对降水酸度的影响分析——以重庆为例

利用重庆市主城区5年的酸雨观测资料和降水资料,采用统计和建模的方法分析了各次降水的降水量对酸雨的影响。结果表明,降水量对酸雨的影响非常明显。降水pH值随降水量的变化总体呈双谷W型,第一个最低值位于17mm的降水量附近,pH低至3.8;第二个最低值位于40mm的降水量附近,pH低至4.0。酸雨频率的变化规律与pH值相反,呈双峰M型。pH值随降水量的变化规律各季节基本一致,除冬季因无大的降水而呈V型外,其余三个季节都呈W型。将pH值随降水量的变化分为3个主要变化区域,构造了pH值随降水量变化的经验公式,该经验公式各组成部分及公式中各参数的物理意义都非常明确,经过意义明确的简单法则和计算即可确定公式中的参数。该经验公式的精度较高,对酸雨的深入研究具有一定的参考价值。

Analysis of Influence of Precipitation on Acidity of Precipitation: A Case Study in Chongqing

Using acid rain data and precipitation data of Chongqing during the past 5 years,through statistic method and modeling method,the influence of precipitation on acidity of precipitation was analyzed.Results indicated that the influence of precipitation on acidity was very clear.With change of precipitation,pH value showed double-valley W styles.The first lowest value was about precipitation of 17mm,where pH lowered at 3.8 whereas the second lowest value was about precipitation of 40mm,where pH lowered at 4.0.Frequency of acid rain showed double-peak M styles,opposite to pH value.In the other three seasons,pH value consistently showed W styles except it showed V style in winter.Dividing the change of pH value with precipitation into three areas,an empirical formula was constructed.Physical meaning of each part and each parameter of the formula was very clear.By simple principle and calculation,the parameters could be confirmed.The empirical formula with high precision has some reference value for research of acid rain.