Abstract ID: 705

First inverse model carbon flux calculations focused on Amazonia

Inverse modeling of atmospheric CO2 observations represents one of the best ways to calculate the carbon balance of large regions like sections of Amazonia. Using CO2 observations made aboard aircraft above Santarem (SAN) between 2001 - 2008, we calculate CO2 sources and sinks for Amazonia within the CarbonTracker data assimilation system (carbontracker.noaa.gov). In the past, CarbonTracker has focused on North America, but in this study the focus is on South America and in particular Amazonia. For this implementation of CarbonTracker, we will simulate atmospheric transport over South America at a horizontal resolution of 1 degree, which should improve our ability to simulate our atmospheric CO2 observations. The CarbonTracker method uses atmospheric observations to optimize a “first-guess” of the surface sources and sinks -- in this case from a modified version of the CASA-GFED biosphere model. Based on preliminary research, we expect the CarbonTracker inversion to slightly increase the sink present in the CASA model on an annual mean basis. However, “forward” simulations of the CASA fluxes within CarbonTracker suggest that the Amazonian biosphere exhibits considerably more variability in source and sink behavior than is represented in the CASA model. In addition to using aircraft vertical profile data, we will also use well-calibrated in situ CO2 data collected atop the km 67 tower at Santarem. The aircraft and tower data will be used in conjunction with discrete and continuous data collected at the Atlantic coast of Brazil, that will help form the baseline for the observed variations at Santarem. This study represents the initial effort to calculate Amazonian carbon balance with a regional focus but integrated within a global carbon cycle calculation.

Session:  Carbon - Scaling carbon fluxes to the region from measurements in plots, towers, and aircraft.

Presentation Type:  Poster