Satellite-based estimates of decline and rebound in China's CO$_2$ emissions during COVID-19 pandemic

TL;DR

This study uses satellite data to track daily CO₂ emission changes in China during COVID-19, revealing an initial decline followed by a rebound as economic activity recovered.

Contribution

It introduces a satellite-based method to estimate sector- and region-specific CO₂ emissions, providing independent and spatially detailed insights beyond activity indicators.

Findings

China's CO₂ emissions dropped 11.5% from Jan-Apr 2020 compared to 2019

Emissions rebounded to pre-pandemic levels with economic recovery

Satellite observations enable detailed, independent emission tracking

Abstract

Changes in CO$_2$ emissions during the COVID-19 pandemic have been estimated from indicators on activities like transportation and electricity generation. Here, we instead use satellite observations together with bottom-up information to track the daily dynamics of CO$_2$ emissions during the pandemic. Unlike activity data, our observation-based analysis can be independently evaluated and can provide more detailed insights into spatially-explicit changes. Specifically, we use TROPOMI observations of NO$_2$ to deduce ten-day moving averages of NO$_x$ and CO$_2$ emissions over China, differentiating emissions by sector and province. Between January and April 2020, China's CO$_2$ emissions fell by 11.5% compared to the same period in 2019, but emissions have since rebounded to pre-pandemic levels owing to the fast economic recovery in provinces where industrial activity is concentrated.