Terrestrial Carbon Sinks for the United States Predicted from MODIS Satellite Data and Ecosystem Modeling
Christopher
Potter, NASA Ames Research Center, cpotter@mail.arc.nasa.gov
(Presenting)
Steven
Klooster, California State University Monterey Bay, sklooster@mail.arc.nasa.gov
Alfredo
Huete, University of Arizona, ahuete@Ag.arizona.edu
Vanessa
Genovese, California State University Monterey Bay, vbrooks@mail.arc.nasa.gov
A simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of the conterminous United States over the period 2001-2004. Predicted net ecosystem production (NEP) flux for atmospheric CO2 in the U.S. was estimated as annual net sink of about +0.2 Pg C in 2004. Regional climate patterns were reflected in the predicted annual NEP flux from the model, which showed extensive carbon sinks in ecosystems of the southern and eastern regions in 2003-2004, and major carbon source fluxes from ecosystems in the Rocky Mountain and Pacific Northwest regions in 2003-2004. As demonstrated though tower site comparisons, NPP modeled with monthly MODIS Enhanced Vegetation Index (EVI) inputs closely resembles both the measured high- and low-season carbon fluxes. Areas of the country that show consistently high carbon sink fluxes in terrestrial ecosystems on a yearly basis are the southern Appalachian Mountains, the western Gulf Coast states, the northern Rocky Mountains, and Sierra Nevada Mountains. Because seasonal climate and atmospheric circulation patterns are likely to differ substantially between these widespread areas of the country, new intensive study campaigns for NACP must be specifically tailored to each of these four priority regions with careful attention to the measurement network requirements for continuous atmospheric CO2 monitoring.