基于CO2关联的沈阳市NH3浓度影响因素探究OA

Atmospheric ammonia(NH3)exerts direct and indirect impacts on air quality,ecosystems and global climate change.Since NH3 is not included in conventional air quality monitoring items,great uncertainties were brought to the implementation of ammonia pollution control in Shenyang.Taking Shenyang as the research area,this study explored the seasonal variation characteristics,influencing factors and transmission pathways of atmospheric NH3 in summer and winter,and put forward targeted control suggestions by adopting the random forest model,backward trajectory analysis and other methods.The results showed that the average NH3 concentration in Shenyang was higher in summer than in winter.In both seasons,atmospheric NH3 concentrations were characterized by higher values in the daytime and lower values at night.Large fluctuations in NH3 concentrations were observed in summer,while a single peak variation pattern was presented in winter.Meteorological factors were identified as the dominant factors affecting NH3 concentration variations.In addition,the influences of CO2 and CH4 concentrations on NH3 were also non-negligible.The atmospheric NH3 concentrations in Shenyang during summer and winter were jointly affected by surrounding provinces and neighboring countries.Air mass transport directions were complicated in summer,whereas a single transport direction was dominated in winter.