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  • Regional Inversion Shows Promise in Capturing Extreme‐Event‐Driven CO 2 Flux Anomalies but Is Limited by Atmospheric CO 2 Observational Coverage
Title: Regional Inversion Shows Promise in Capturing Extreme‐Event‐Driven CO 2 Flux Anomalies but Is Limited by Atmospheric CO 2 Observational Coverage
Abstract Extreme climate events are becoming more frequent, with poorly understood implications for carbon sequestration by terrestrial ecosystems. A better understanding will critically depend on accurate and precise quantification of ecosystems responses to these events. Taking the 2019 US Midwest floods as a case study, we investigate current capabilities for tracking regional flux anomalies with “top‐down” inversion analyses that assimilate atmospheric CO2observations. For this analysis, we develop a regionally nested version of the NASA Carbon Monitoring System‐Flux system for North America (CMS‐Flux‐NA) that allows high resolution atmospheric transport (0.5° × 0.625°). Relative to a 2018 baseline, we find the 2019 US Midwest growing season net carbon uptake is reduced by 11–57 TgC (3%–16%, range across assimilated CO2data sets). These estimates are found to be consistent with independent “bottom‐up” estimates of carbon uptake based on vegetation remote sensing (15–78 TgC). We then investigate current limitations in tracking regional carbon budgets using “top‐down” methods. In a set of observing system simulation experiments, we show that the ability of atmospheric CO2inversions to capture regional carbon flux anomalies is still limited by observational coverage gaps for both in situ and satellite observations. Future space‐based missions that allow for daily observational coverage across North America would largely mitigate these observational gaps, allowing for improved top‐down estimates of ecosystem responses to extreme climate events.  more » « less
Award ID(s):
2017870
PAR ID:
10541248
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AGU
Date Published:
Journal Name:
Journal of Geophysical Research: Atmospheres
Volume:
129
Issue:
6
ISSN:
2169-897X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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