In this paper,three portable greenhouse gas analyzers were used to continuously observe the atmospheric CO2 and CH4 concentrations at the heights of 255 and 500m at Shanghai Tower and 25m at Pudong New Area Environmental Monitoring Station from 6 December 2021 to 31 March 2022.The results indicated that:(1)the diurnal variabilities of the greenhouse gases at different heights in the city were different,with low value in daytime and high value at night for the 25m height,but opposite for the 255 and 500m heights.The CO2 and CH4 concentrations at each height were affected obviously by atmospheric boundary layer height,suggesting that vertical observation in cities must consider the variability of atmospheric boundary layer.(2)The vertical difference of the CO2 and CH4 concentrations were affected by anthropogenic activities and meteorological conditions,which can trace local and regional contributions.(3)The CO2 and CH4 concentrations were significantly correlated at each height(25,255,500m),and the correlation was weaker at greater height due to the interference of more emission and weak homology.The vertical observation of urban greenhouse gas concentration provided unique information that cannot be obtained from the horizontal observation.Therefore,three-dimensional greenhouse gas monitoring in cities was required to capture the change of atmospheric greenhouse gas concentration and to serve the urban carbon emission reduction policy.
关键词
CO2和CH4浓度/垂直差异/上海/大气边界层高度/CH4∶CO2比值
Key words
CO2 and CH4 concentration/vertical difference/Shanghai/atmospheric boundary layer height/CH4∶CO2 ratio
万方数据