Using Remote-Sensing Derived Estimates of Soil Moisture to Constrain and Improve Terrestrial Biosphere Model Predictions of Terrestrial Carbon Fluxes

Abstract:

In both natural and managed ecosystems the fluxes of carbon into and out of the ecosystem are strongly connected to the dynamics of soil moisture. In this study, we examine how remote-sensing derived estimates of root zone soil moisture (RZSM) available from the AirMOSS P-band radar remote sensing instrument can be used to constrain terrestrial biosphere model predictions of carbon, water and energy fluxes on timescales ranging from hours to decades. Results from ecosystems in the continental US, including an eastern temperate forest, a mid-western grassland, a Californian oak-savannah, and a

western conifer forest, indicate that RZSM measurements can provide an important data-constraint on terrestrial biosphere model predictions of how plant photosynthesis and ecosystem respiration respond to changes in soil moisture availability. In doing so, they pave the way for improved estimates of key model parameters and for reducing uncertainty in regional and continental carbon budgets.