@Article{HerrmannFrei:2011:RoCoSy,
author = "Herrmann, Valdir and Freitas, Saulo Ribeiro de",
affiliation = "Climatempo Meteorology, S{\~a}o Paulo, SP, Brazil,
valdir@climatempo.com.br. and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "Atmospheric CO2 budget over the Amazon basin: the role of
convective systems",
journal = "Revista Brasileira de Meteorologia",
year = "2011",
volume = "26",
number = "4",
pages = "529 - 540",
month = "dez.",
keywords = "Keywords: carbon budget, Amazon basin, convective transport,
Balan{\c{c}}o de Carbono, Amaz{\^o}nia, Transporte Convectivo,
Fluxos de CO2.",
abstract = "This work studies the atmospheric CO2 budget in the Amazon basin,
focusing on the role of shallow and deep convective systems. The
vertical redistribution of CO2 is numerically simulated using an
Eulerian transport model coupled to the Brazilian developments on
the Regional Atmospheric Modeling System (BRAMS). The transport
model includes grid-scale advection, diffusion in the PBL
(Planetary Boundary Layer) and convective transport by sub-grid
shallow and deep moist convection. In the simulation, the mass
conservation equation is solved for six tracers, including or not
the shallow and deep moist convection terms. The rectifier effect
is also showed through simulation of the transport to the free
troposphere of PBL air masses with low CO2 concentrations due to
assimilation by vegetation during the afternoon, when both CO2
fixation and convection are at their peak. The model is applied to
simulate July 2001 with a 30 km grid resolution covering the
northwest part of South America. We compare the model results with
airborne CO2 observations collected in the Amazon basin during the
2001 CLAIRE field campaign. , CO2 flux. RESUMO: Este trabalho
apresenta um estudo do balan{\c{c}}o de CO2 na atmosfera da bacia
Amaz{\^o}nica, enfocando o papel dos sistemas convectivos rasos e
profundos. A redistribui{\c{c}}{\~a}o vertical de CO2 {\'e}
simulada numericamente usando um modelo de transporte Euleriano
acoplado ao modelo atmosf{\'e}rico BRAMS (Brazilian developments
on the Regional Atmospheric Modeling System). O modelo de
transporte inclui o termo de advec{\c{c}}{\~a}o, associado ao
transporte resolvido, al{\'e}m dos termos de transporte, n{\~a}o
resolvidos como difus{\~a}o turbulenta na CLP (Camada Limite
Planet{\'a}ria), e transporte convectivo, associado a cumulus
rasos e profundos. Na simula{\c{c}}{\~a}o utilizam-se seis
tra{\c{c}}adores, onde a equa{\c{c}}{\~a}o da
conserva{\c{c}}{\~a}o da massa {\'e} resolvida incluindo ou
n{\~a}o o termo convectivo profundo ou o termo convectivo raso. O
efeito retificador {\'e} descrito na simula{\c{c}}{\~a}o
num{\'e}rica atrav{\'e}s do transporte para a troposfera livre
de massas de ar da CLP com baixas concentra{\c{c}}{\~o}es de
CO2, devido {\`a} atividade de assimila{\c{c}}{\~a}o realizada
pela vegeta{\c{c}}{\~a}o no per{\'{\i}}odo diurno, quando os
dois processos, fixa{\c{c}}{\~a}o e atividade convectiva
est{\~a}o no {\'a}pice. A simula{\c{c}}{\~a}o foi realizada
para o m{\^e}s de julho de 2001, com uma resolu{\c{c}}{\~a}o de
30 km na grade, cobrindo a por{\c{c}}{\~a}o noroeste da
Am{\'e}rica do Sul. Compara{\c{c}}{\~o}es dos resultados do
modelo com dados de CO2 , observados na bacia Amaz{\^o}nica
durante o experimento CLAIRE 2001, tamb{\'e}m s{\~a}o
mostradas.",
issn = "0102-7786",
language = "pt",
targetfile = "a03v26n4.pdf",
urlaccessdate = "22 jan. 2021"
}