Atmospheric CO2 Budget over Amazon Basin: The Role of the Convective Systems
Valdir
Inácio
Herrmann, USP, valher@model.iag.usp.br
(Presenting)
Saulo
Ribeiro de
Freitas, CPTEC-INPE, sfreitas@cptec.inpe.br
Robert
Chatfield, NASA, chatfield@clio.arc.nasa.gov
This work studies the CO2 budget in the atmosphere on Amazon basin focusing the role of the shallow and deep convective systems. The vertical redistribution of the CO2 by these systems is numerically simulated using a Eulerian transport model coupled to a regional atmospheric model (RAMS). The transport model includes advection at grid scale, diffusion in the planetary boundary layer (PBL) and convective transport by sub-grid shallow and deep moist convection. We explore also two different approaches for the CO2 biogenic surface fluxes. The simulation is carried out with 6 tracers whose mass conservation equation is resolved including or not the moist convective deep and shallow transport. In that way, the role of these systems is clearly showed. The rectifier effect is also depicted through the transport to the free troposphere of PBL air masses with low CO2 concentration due to activity of assimilation by the vegetation in the period between the noon and end of the afternoon, when this process and the convective activity are in the apex. The model is applied to July 2001 with a 30 km grid resolution covering the north portion of the South America. For this case, we compare the model results with CO2 observations collected on Amazon basin during CLAIRE experiment.