多源碳卫星近地面XCO_(2)及人为CO_(2)排放量特征分析

Characteristic Analysis of Near-ground XCO_(2) and Anthropogenic CO_(2) Emissions from Multi-source Carbon Satellites

为定量分析近地面XCO_(2)与人为碳排放的时空特征,文章首先使用GOSAT、OCO-2卫星长时间序列近地面XCO_(2)数据集分析成渝地区XCO_(2)时空特征;再对XCO_(2)浓度及人为CO_(2)排放量进行EMD时间维分解,分析四川、重庆、北京不同时间尺度的变化特征。并用北京地面观测站点数据与卫星数据对比验证数据可靠性。结果表明:(1)201001-202112成渝地区近地面年均XCO_(2)浓度集中在389×10^(-6)~410×10^(-6)内,总体呈条带状分布,总年均增幅达19.6×10^(-6);XCO_(2)低值区位于西部、高值区位于中部及东部。(2)EMD及EEMD分解201001-202112成渝地区XCO_(2)后各IMF具有年际变化和季节变化的时间周期特性,RSE仍呈上升趋势。IMF1~IMF4为人为源碳排放,IMF5~IMF7为自然源碳排放。结果存在一定滞后性。(3)EMD分解201901-202012四川省、重庆、北京日尺度人为CO_(2)总排放量,新冠期间,人为CO_(2)排放量大幅降低,四川下降392.076 t,重庆下降306.277 t,北京下降87.651 t,下降结果不存在明显滞后性。

In order to quantitatively analyze the spatiotemporal characteristics of near-surface XCO_(2)and anthropogenic carbon emissions,long-term near-surface XCO_(2)datasets of GOSAT and OCO-2 satellites was used to analyze the spatiotemporal characteristics of XCO_(2)in Chengdu-Chongqing area.Then the EMD time-dimension decomposition of XCO_(2)concentration and anthropogenic CO_(2)emissions was carried out to analyze the characteristics of changes at different time scales in Sichuan,Chongqing and Beijing.The reliability of the data was verified by comparing the data from Beijing ground observation station and satellite data.The results show that the annual average XCO_(2)in Chengdu-Chongqing area is concentrated in 389×10^(-6)to 410×10^(-6)during Jan.2010 to Dec.2021,with the overall annual average increase rate as 19.6×10^(-6).The low value of XCO_(2)is located in the west,while the high value is located in the middle and east.EMD and EEMD decomposition after XCO_(2)in Chengdu-Chongqing area during Jan.2010 to Dec.2021,each IMF has the time cycle characteristics of inter-annual and seasonal variation,and RSE still shows an upward trend.IMF1~IMF4 is carbon emissions from human sources and IMF5~IMF7 is carbon emissions from natural sources.The result have certain lag.Total daily anthropogenic CO_(2)emissions of Sichuan Province,Chongqing and Beijing are decomposed by EMD from January 2019 to December 2020.During the COVID-19 period,anthropogenic CO_(2)emissions significantly decreased,with Sichuan decreasing 392.076 t,Chongqing decreasing 306.277 t and Beijing decreasing 87.651 t.There is no obvious lag in the decline results.