Constraining China's land carbon sink from emerging satellite CO2 observations: Progress and challenges

Land carbon sink is a vital component for the achievement of China's ambitious carbon neutrality goal, but its magnitude is poorly known. Atmospheric observations and inverse models are valuable tools to constrain the China's land carbon sink. Space-based CO2 measurements from satellites form an emerging data stream for application of such atmospheric inversions. Here, we reviewed the satellite missions that is dedicated to the monitoring of CO2, and the recent progresses on the inversion of China's land carbon sink using satellite CO2 measurements. We summarized the limitations and challenges in current space platforms, retrieval algorithms, and the inverse modeling. It is shown that there are large uncertainties of contemporary satellite-based estimates of China's land carbon sink. We discussed future opportunities of continuous improvements in three aspects to better constrain China's land carbon sink with space-based CO2 measurements.

Automated summary

This article reviews satellite missions dedicated to CO2 monitoring and recent progress in using satellite CO2 measurements to estimate China's land carbon sink. The limitations and challenges of current space platforms, retrieval algorithms, and inverse modeling are summarized. The study highlights the large uncertainties in contemporary satellite-based estimates of China's land carbon sink and discusses opportunities for continuous improvements in better constraining it using space-based CO2 measurements.