Investigating Impacts of New In-Situ Observations on the Inference of North American Terrestrial Biogenic CO2 Fluxes Using a High-Resolution Inversion System

The number of tower-based carbon dioxide (CO2) measurements operating within North America has expanded greatly in the last decade, especially in the eastern US. These measurements have the potential to greatly improve the resolution and accuracy of inverse estimates of biospheric fluxes across the continent. We investigate the value of these observations within the CarbonTracker-Lagrange atmospheric inversion system. We perform inversions using this full suite of in situ data and explore: 1) the impact of the expanded tower network via data-removal experiments and 2) seasonal and interannual variability in fluxes over the past decade at continental and regional scales. We investigate the impact of additional measurements on the estimated biogenic fluxes and their uncertainties for the continent of North America and evaluate our posterior flux estimates and simulated mole fractions with independent in situ observations including both the AmeriFlux network and ACT-America airborne CO2 observations.