CAIO SILVESTRE DE CARVALHO CORREIA

CAIO SILVESTRE DE CARVALHO CORREIA

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Sixteen years of MOPITT satellite data strongly constrain Amazon CO fire emissions
2022 - NAUS, STIJN; DOMINGUES, LUCAS G.; KROL, MAARTEN; LUIJKX, INGRID T.; GATTI, LUCIANA V.; MILLER, JOHN B.; GLOOR, EMANUEL; BASU, SOURISH; CORREIA, CAIO; KOREN, GERBRAND; WORDEN, HELEN M.; FLEMMING, JOHANNES; PETRON, GABRIELLE; PETERS, WOUTER
Despite the consensus on the overall downward trend in Amazon forest loss in the previous decade, estimates of yearly carbon emissions from deforestation still vary widely. Estimated carbon emissions are currently often based on data from local logging activity reports, changes in remotely sensed biomass, and remote detection of fire hotspots and burned area. Here, we use 16 years of satellite-derived carbon monoxide (CO) columns to constrain fire CO emissions from the Amazon Basin between 2003 and 2018. Through data assimilation, we produce 3 d average maps of fire CO emissions over the Amazon, which we verified to be consistent with a long-term monitoring programme of aircraft CO profiles over five sites in the Amazon. Our new product independently confirms a long-term decrease of 54% in deforestation-related CO emissions over the study period. Interannual variability is large, with known anomalously dry years showing a more than 4-fold increase in basin-wide fire emissions relative to wet years. At the level of individual Brazilian states, we find that both soil moisture anomalies and human ignitions determine fire activity, suggesting that future carbon release from fires depends on drought intensity as much as on continued forest protection. Our study shows that the atmospheric composition perspective on deforestation is a valuable additional monitoring instrument that complements existing bottom-up and remote sensing methods for land-use change. Extension of such a perspective to an operational framework is timely considering the observed increased fire intensity in the Amazon Basin between 2019 and 2021.
Background concentrations of CO2, CO and N2O in Brazilian coast
2020 - MARANI, L.; BORGES, V.F.; GATTI, L.V.; DOMINGUES, L.G.; CORREIA, C.S.C.; BASSO, L.S.; SANTOS, R.S. dos; CRISPIM, S.P.; NEVES, R.A.L.; GLOOR, M.; MILLER, J.B.
Measurement program of GHG vertical profiles at Amazon
2020 - GATTI, L.V.; MILLER, J.B.; GLOOR, M.; DOMINGUES, L.G.; CORREIA, C.S.C.; BASSO, L.; MARANI, L.; CASSOL, H.L.G.; TEJADA, G.; BORGES, V.F.; PETERS, W.; CRISPIM, S.P.; LOPES, R.; RIBEIRO, M.M.; MORAIS, C.S.; AQUINO, C.A.B.
A new background method for greenhouse gases flux calculation based in back-trajectories over the Amazon
2020 - DOMINGUES, LUCAS G.; GATTI, LUCIANA V.; AQUINO, AFONSO; SÁNCHEZ, ALBER; CORREIA, CAIO; GLOOR, MANUEL; PETERS, WOUTER; MILLER, JOHN; TURNBULL, JOCELYN; SANTANA, RICARDO; MARANI, LUCIANO; CÂMARA, GILBERTO; NEVES, RAIANE; CRISPIM, STÉPHANE
The large amount of carbon stored in trees and soils of the Amazon rain forest is under pressure from land use as well as climate change. Therefore, various efforts to monitor greenhouse gas exchange between the Amazon forest and the atmosphere are now ongoing, including regular vertical profile (surface to 4.5 km) greenhouse gas measurements across the Amazon. These profile measurements can be used to calculate fluxes to and from the rain forest to the atmosphere at large spatial scales by considering the enhancement or depletion relative to the mole fraction of air entering the Amazon basin from the Atlantic, providing an important diagnostic of the state, changes and sensitivities of the forests. Previous studies have estimated greenhouse gas mole fractions of incoming air (‘background’) as a weighted mean of mole fractions measured at two background sites, Barbados (Northern Hemisphere) and Ascension (Southern hemisphere) in the Tropical Atlantic, where the weights were based on sulphur hexafluoride (SF6) measured locally (in the Amazon vertical profiles) and at the two background sites. However, this method requires the accuracy and precision of SF6 measurements to be significantly better than 0.1 parts per trillion (picomole mole􀀀1), which is near the limit for the best SF6 measurements and assumes that there are no SF6 sources in the Amazon basin. We therefore present here an alternative method. Instead of using SF6, we use the geographical position of each air-mass back-trajectory when it intersects the limit connecting these two sites to estimate contributions from Barbados versus Ascension. We furthermore extend the approach to include an observation site further south, Cape Point, South Africa. We evaluate our method using CO2 vertical profile measurements at a coastal site in Brazil comparing with values obtained using this method where we find a high correlation (r2 = 0.77). Similarly, we obtain good agreement for CO2 background when comparing our results with those based on SF6, for the period 2010–2011 when the SF6 measurements had excellent precision and accuracy. We also found high correspondence between the methods for background values of CO, N2O and CH4. Finally, flux estimates based on our new method agree well with the CO2 flux estimates for 2010 and 2011 estimated using the SF6-based method. Together, our findings suggest that our trajectory-based method is a robust new way to derive background air concentrations for the purpose of greenhouse gas flux estimation using vertical profile data.
Modelling the radiative effects of smoke aerosols on carbon fluxes in Amazon
2017 - MOREIRA, DEMERVAL S.; LONGO, KARLA M.; FREITAS, SAULO R.; YAMASOE, MARCIA A.; MERCADO, LINA M.; ROSARIO, NILTON E.; GLOOR, EMANUEL; VIANA, ROSANE S.M.; MILLER, JOHN B.; GATTI, LUCIANA V.; WIEDEMANN, KENIA T.; DOMINGUES, LUCAS K.G.; CORREIA, CAIO C.S.
Every year, a dense smoke haze of regional dimensions covers a large portion of South America originated from fire activities in the Amazon Basin and Central parts of Brazil during the dry/biomass-burning season between August and October. Over a large portion of South America, the average aerosol optical depth at 550 nm exceeds 1.0 during the fire season while the background value during the rainy season is below 0.2. Smoke aerosol particles increase scattering and absorption of the incident solar radiation. The regional-scale aerosol layer reduces the amount of solar energy reaching the surface, cools the near surface air, and increases the diffuse radiation fraction over a large disturbed area of the Amazon rainforest. These factors affect the energy and CO2 fluxes at the surface. In this work, we applied a fully integrated atmospheric model to assess the impact of smoke aerosols in CO2 fluxes in the Amazon region during 2010. We address the effects of the attenuation of the solar global radiation and the enhancement of the diffuse solar radiation flux inside the canopy. Our results indicated that the smoke aerosols led to an increase of about 22 % of the gross primary productivity of Amazonia, 9 % of plant respiration and a decline in soil respiration from of 3 %. Consequently, Amazonia net ecosystem exchange during September 2010 dropped from +101 to −104 TgC when the aerosol effects were considered, mainly due to the aerosol diffuse radiation effect. For the forest biome, our results pointed to a dominance of the diffuse radiation effect on CO2 fluxes, reaching a balance of 50 % – 50 % between the diffuse and direct aerosol effects for high aerosol loads. For C3 grass type and cerrado, as expected, the contribution of the diffuse radiation effect is much lower, tending to zero with the increase of aerosol load. That is, the Amazon during the dry season, in the presence of high smoke aerosol loads, change from being a source to be a sink of CO2 to the atmosphere.
Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements
2014 - GATTI, L.V.; GLOOR, M.; MILLER, J.B.; DOUGHTY, C.E.; MALHI, Y.; DOMINGUES, L.G.; BASSO, L.S.; MARTINEWSKI, A.; CORREIA, C.S.C.; BORGES, V.F.; FREITAS, S.; BRAZ, R.; ANDERSON, L.O.; ROCHA, H.; GRACE, J.; PHILLIPS, O.L.; LLOYD, J.