Temporal Variations in Methane Concentrations and Influencing Factors at Typical Urban Sites in the Yangtze River Delta
Methane(CH4)is a greenhouse gas with significant impact on global warming.It exhibits complex variability and influen-cing factors,especially in regions abundant in both human activities and natural resources.Suzhou,as one of the economically devel-oped cities in the Yangtze River Delta,holds significance in analyzing the characteristics and influencing factors of CH4.Based on on-line CH4 observation data from 2018 to 2022 in Suzhou,this study employed various statistical analysis methods,including machine learning algorithms,HYSPLIT backward trajectories,and potential source contribution function(PSCF),to analyze CH4 variations,correlations,and major potential source areas in Suzhou.Suzhou's CH4 concentration shows a characteristic of higher levels in autumn and lower levels in spring,with a unimodal diurnal variation pattern.Meteorological normalization indicates that CH4 concentrations were highest in 2019 over the past four years,primarily due to anthropogenic emissions.Wind speed demonstrates a higher correlation with CH4 compared to temperature and humidity.Air masses originating from the sea exhibit lower CH4 concentrations,while those starting inland show higher levels,influenced by transport from upstream cities.The main potential source areas for CH4 are distributed in the southeastern part of Anhui Province and the northwestern part of Zhejiang Province,with the concentration contribution values forming a circular distribution pattern gradually decreasing from Suzhou towards the surrounding areas.
greenhouse gasmethanebackward trajectoryimpact of the epidemic
NETL
NSTL
万方数据
