不同等级降水对廊坊市污染物浓度的影响分析

Analysis on the Effect of Different Levels of Precipitation on Pollutant Concentration in Langfang City

摘要: 利用2013~2016年廊坊市气象观测站小时降水资料、环保局空气质量监测药材公司站六类主要污染物(SO₂、NO₂、CO、O₃、PM₁₀和PM_2.5)相应浓度数据，利用数理统计方法分析了不同等级降水强度、不同降水时段、不同季节降水性质等6个方面，研究分析了降水对主要污染物浓度的影响。结果表明：1) 在不同小时降水强度下，大雨和中雨的稀释作用要优于小雨；2) 六类污染物对降水有较明显差异，PM₁₀、PM_2.5和SO₂浓度下降率最明显，达到60%，O₃的下降率最弱，对降水强度变化不敏感；3) 降雨作用优于降雪，降水对污染物浓度下降率普遍高于降雪；4) 夏季降水的稀释作用最强，其次是秋季，春季和冬季最差，这也和降水强度和降水量相关；5) 降水结束2小时污染物浓度下降率又比降水结束1小时偏高。

Abstract: Using the hourly precipitation data of the meteorological observation station in Langfang City for 2013-2016 and the corresponding concentration data of six major pollutants (SO₂, NO₂, CO, O₃, PM₁₀ and PM_2.5) at the Pharmaceutical Company Station of the Environmental Protection Bureau Air Quality Monitoring Station, the effects of precipitation on the concentration of major pollutants were studied by using mathematical statistical methods, such as intensity of precipitation of different grades, different precipitation periods and nature of precipitation of different seasons. The results show that: 1) Under different precipitation intensity, the dilution of heavy rain and moderate rain is better than light rain; 2) The six types of pollutants have significant differences in precipitation, and the concentration reduction rates of PM₁₀, PM_2.5, and SO₂ are the most obvious, reaching 60%, and the rate of decline of O₃ is the weakest, and it is not sensitive to the changes in precipitation intensity; 3) The effect of rainfall is better than snowfall, and the reduction rate of pollutant concentration by precipitation is generally higher than that by snowfall; 4) Summer precipitation has the strongest dilution, followed by autumn, spring and winter, which is also related to precipitation intensity and precipitation; 5) The rate of reduction of pollutant concentration at the end of 2 hours of precipitation is higher than that at the end of 1 hour of precipitation.