Open AccessShort-term reduction of regional enhancement of atmospheric CO2 in China during the first COVID-19 pandemic period
Author(s) -
Sojung Sim,
Haeyoung Lee,
Eunsil Oh,
Sumin Kim,
Philippe Ciais,
Shilong Piao,
John C. Lin,
Derek V. Mallia,
Sepyo Lee,
Yeon-Hee Kim,
Hoonyoung Park,
Jeongmin Yun,
Sujong Jeong
Publication year - 2022
Publication title -
environmental research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.37
H-Index - 124
ISSN - 1748-9326
DOI - 10.1088/1748-9326/ac507d
Subject(s) - china , covid-19 , environmental science , atmospheric sciences , climatology , emission inventory , meteorology , geography , air quality index , physics , medicine , geology , disease , archaeology , pathology , infectious disease (medical specialty)
Recent studies have reported a 9% decrease in global carbon emissions during the COVID-19 lockdown period; however, its impact on the variation of atmospheric CO 2 level remains under question. Using atmospheric CO 2 observed at Anmyeondo station (AMY) in South Korea, downstream of China, this study examines whether the decrease in China’s emissions due to COVID-19 can be detected from the enhancement of CO 2 mole fraction (ΔCO 2 ) relative to the background value. The Weather Research and Forecasting–Stochastic Time-Inverted Lagrangian Transport model was applied to determine when the observed mole fractions at AMY were affected by air parcels from China. Atmospheric observations at AMY showed up to a −20% (−1.92 ppm) decrease in ΔCO 2 between February and March 2020 compared to the same period in 2018 and 2019, particularly with a −34% (−3.61 ppm) decrease in March. ΔCO, which was analyzed to explore the short-term effect of emission reductions, had a decrease of −43% (−80.66 ppb) during the lockdown in China. Particularly in East China, where emissions are more concentrated than in Northeast China, ΔCO 2 and ΔCO decreased by −44% and −65%, respectively. The ΔCO/ΔCO 2 ratio (24.8 ppb ppm −1 ), which is the indicator of emission characteristics, did not show a significant difference before and after the COVID-19 lockdown period ( α = 0.05), suggesting that this decrease in ΔCO 2 and ΔCO was associated with emission reductions rather than changes in emission sources or combustion efficiency in China. Reduced carbon emissions due to limited human activity resulted in a decrease in the short-term regional enhancement to the observed atmospheric CO 2 .