COS-derived GPP relationships with temperature and light help explain high-latitude atmospheric CO 2 seasonal cycle amplification

This is the authors' abstract. We don't add key points for this paper.

Significance Interactions between terrestrial carbon dioxide (CO 2 ) fluxes and climate or terrestrial ecosystem feedbacks exert a large uncertainty in climate projections. This uncertainty arises in part from poor quantification of gross CO 2 fluxes and their sensitivity to climate change over large spatial scales. Here, we demonstrate the usefulness of carbonyl sulfide (COS) for quantifying photosynthetic CO 2 uptake in the Arctic and Boreal ecosystems despite uncertainties in COS sources and sinks. The results highlight how the combination of atmospheric COS and CO 2 observations provides insights into past terrestrial ecosystem changes and can be utilized as a tool for direct quantification of these feedbacks impacted by climate change over the Arctic and Boreal ecosystems in the future.