Study On The Distribution Characteristics Of Atmospheric Carbon Dioxide Column Concentration And Anthropogenic Emissions In The China-Pakistan Regio

This paper divides China and Pakistan into seven regions and divides Pakistan into administrative levels,combining the OCO-2 satellite secondary data of XCO₂ products,ODIAC emission inventory,EDGAR emission inventory and China Emission Accounts and Datasets and other supplementary data（OMI NO₂ tropospheric column,population density,nightlights,fire position,surface coverage）,the distribution characteristics of atmospheric carbon dioxide and anthropogenic emissions in China and Pakistan are analyzed by using satellite dataset to calculate anthropogenic emissions and correlation test among datasets.The results show that the XCO₂ distribution in China and Pakistan has a seasonal trend,showing high in spring and winter,low in summer and autumn.The XCO₂ in China increased continuously from year 2016 to 2022,showing a“Fast-slow-fast-slow”trend,growth slowed in 2019-2022.The concentration of XCO₂ in various regions of China is increasing continuously,with the high concentration in coastal areas and the low concentration in northwest,southwest and northeast areas.The distribution trend of XCO₂ in China is similar to the data of nightlights and population distribution,the high values are concentrated in the locations with developed economy,strong human activities,vegetation and wasteland on the surface,and urban type（cement land）.The satellite anthropogenic emission data calculated by removing background and trend values have similar spatial distribution to ODIAC emission data and EDGAR emission data.The high value of China’s anthropogenic emissions is concentrated in the coastal and central regions,while the low value is concentrated in the northwest region.By comparison with the carbon accounting database,satellite observations underestimate anthropogenic emissions in Inner Mongolia Province,which may be related to the selection of background values.The country’s high levels of anthropogenic emissions are concentrated along the China-pakistan economic corridor（CPEC）and in economically developed cities such as Karachi and Lahore.Among provincial administrative units,Punjab province has the highest carbon dioxide emissions,sindh,KPK and Baluchistan.The correlation analysis of satellite anthropogenic emissions and ODIAC emissions,EDGAR emissions and other auxiliary data showed good consistency,especially after removing the low values.The paper presents the analysis results of CO₂ concentrations and anthropogenic emissions from OCO-2 satellite data at regional and provincial scales in China and Pakistan,after that,man-made emissions at the city scale can be monitored with multi-source satellite data.