LUCAS GATTI DOMINGUES
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Artigo IPEN-doc 22703 CHsub(4) concentrations over the Amazon from GOSAT consistent with in situ vertical profile data2016 - WEBB, ALEX J.; BOSCH, HARTMUT; PARKER, ROBERT J.; GATTI, LUCIANA V.; GLOOR, EMANUEL; PALMER, PAUL I.; BASSO, LUANA S.; CHIPPERFIELD, MARTIN P.; CORREIA, CAIO S.C.; DOMINGUES, LUCAS G.; FENG, LIANG; GONZI, SIEGFRIED; MILLER, JOHN B.; WARNEKE, THORSTEN; WILSON, CHRISTOPHERThe Amazon Basin contains large wetland ecosystems which are important sources of methane (CH4). Space-borne observations of atmospheric CH4 provide constraints on emissions from these remote ecosystems, but lack of validation precludes robust estimates. We present the rst validation of CH4 columns in the Amazon from the Greenhouse gases Observing SATellite (GOSAT) using dedicated vertical pro le measurements of CH4 over ve sites across the Amazon Basin. These aircraft pro les, combined with the TOMCAT stratospheric model, are vertically integrated allowing direct comparison to the GOSAT measurements. The absolute columns agree within uncertainties or show no signi cant di erence at three of the aircraft sites (-1.9 2.2 ppb and 3.6 4.3 ppb at one site with two di erent campaigns; and 3.6 1.7 ppb, and 6.6 2.6 ppb at the other two), whilst at two sites GOSAT XCH4 is shown to be slightly higher than aircraft measurements, by up to approximately 10 ppb in the most di ering case (8.1 2.1 ppb and 9.7 2.8 ppb). The seasonality in XCH4 seen by the aircraft pro les is also well captured. GOSAT observes elevated concentrations in the north-west corner of South America in the dry season and enhanced concentrations elsewhere in the Amazon Basin in the wet season; with the strongest seasonal di erences coinciding with regions in Bolivia known to contain large wetlands. Our results are encouraging evidence that these GOSAT CH4 columns are in good agreement with in situ measurements and can be reliably used to provide new insights into tropical methane emissionsArtigo 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.Artigo IPEN-doc 21306 Response of the Amazon carbon balance to the 2010 drought derived with carbon tracker South America2015 - LAAN-LUIJKCX, I.T. van der; VELDE, I.R. van der; KROL, M.C.; GATTI, L.V.; DOMINGUES, L.G.; CORREIA, C.S.C.; MILLER, J.B.; GLOOR, M.; LEEUWEN, T.T. van; WIEDINMYER, C.; BASU, S.; CLERBAUX, C.; PETERS, W.; KAISER, J.W.