COS-derived GPP relationships with temperature and light help explain high-latitude atmospheric CO <sub>2</sub> seasonal cycle amplification
Lei Hu, S. A. Montzka, Aleya Kaushik, A. E. Andrews, Colm Sweeney, J. B. Miller, Ian Baker, Scott Denning, Elliott Campbell, Yoichi P. Shiga, Pieter P. Tans, M. Carolina Siso, Molly Crotwell, Kathryn McKain, K. W. Thoning, B. D. Hall, Isaac Vimont, James W. Elkins, Mary Whelan, Parvadha Suntharalingam
Abstract
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.