LUCAS GATTI DOMINGUES
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Artigo IPEN-doc 29494 Sixteen years of MOPITT satellite data strongly constrain Amazon CO fire emissions2022 - 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, WOUTERDespite 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.Artigo IPEN-doc 22700 Consistent regional fluxes of CHsub(4) and COsub(2) inferred from GOSAT proxy XCHsub(4)XCOsub(2) retrievals, 2010-20142017 - FENG, LIANG; PALMER, PAUL I.; BÖSCH, HARTMUT; PARKER, ROBERT J.; WEBB, ALEX J.; CORREIA, CAIO S.C.; DEUTSCHER, NICHOLAS M.; DOMINGUES, LUCAS G.; FEIST, DIETRICH G.; GATTI, LUCIANA V.; GLOOR, EMANUEL; HASE, FRANK; KIVI, RIGEL; LIU, YI; MILLER, JOHN B.; MORINO, ISAMU; SUSSMANN, RALF; STRONG, KIMBERLY; UCHINO, OSAMU; WANG, JING; ZAHN, ANDREASWe use the GEOS-Chem global 3-D model of atmospheric chemistry and transport and an ensemble Kalman filter to simultaneously infer regional fluxes of methane (CH4) and carbon dioxide (CO2) directly from GOSAT retrievals of XCH4:XCO2, using sparse ground-based CH4 and CO2 mole fraction data to anchor the ratio. This work builds on previously reported theory that takes advantage that: 1) these ratios are less prone to systematic error than either the full physics data products or the proxy CH4 data products; and 2) the resulting CH4 and CO2 fluxes are self-consistent. We show that a posteriori fluxes inferred from the GOSAT data generally outperform the fluxes inferred only from in situ data, as expected. GOSAT CH4 and CO2 fluxes are consistent with global growth rates for CO2 and CH4 reported by NOAA, and with a range of independent data including in particular new profile measurements (0-7 km) over the Amazon basin that were collected specifically to help validate GOSAT over this geographical region. We find that large-scale multi-year annual a posteriori CO2 fluxes inferred from GOSAT data are similar to those inferred from the in situ surface data but with smaller uncertainties, particularly over the tropics. GOSAT data are consistent with smaller peak-topeak seasonal amplitudes of CO2 than either a priori or the in situ inversion, particularly over the tropics and the southern extra-tropics. Over the northern extra-tropics, GOSAT data show larger uptake than the a priori but less than the in situ inversion, resulting in small net emissions over the year. We also find evidence that the carbon balance of tropical South America was perturbed following the droughts of 2010 and 2012 with net annual fluxes not returning to an approximate annual balance until 2013. In contrast, GOSAT data significantly changed the a priori spatial distribution of CH4 emission with a 40% increase over tropical South America and tropical Asia and smaller decrease over Eurasia and temperate South America. We find no evidence from GOSAT that tropical South American CH4 fluxes were dramatically affected by the two large-scale Amazon droughts. However, we find that GOSAT data are consistent with double seasonal peaks in fluxes that are reproduced over the five years we studied: a small peak in January to April and a larger peak 60 in June to October, which is likely due to superimposed emissions from different geographical regions.