Amazon methane budget derived from multi-year airborne observations highlights regional variations in emissions
| Autor: | Graciela Tejada, Sergio Machado Corrêa, Luana S. Basso, Liana Oighstein Anderson, Luciana V. Gatti, Stephane P. Crispim, John B. Miller, Raiane A.L. Neves, Luciano Marani, Lucas G. Domingues, Egidio Arai, Manuel Gloor, Alber Sanchez, Henrique Luis Godinho Cassol, Caio S. C. Correia, John M. Melack, Luiz E. O. C. Aragão |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
geography
QE1-996.5 geography.geographical_feature_category Amazon rainforest Atmospheric methane Tropics Wetland Geology Seasonality medicine.disease Atmospheric sciences Methane Environmental sciences chemistry.chemical_compound chemistry Soil water medicine General Earth and Planetary Sciences Environmental science GE1-350 Precipitation General Environmental Science |
| Zdroj: | Communications Earth & Environment, Vol 2, Iss 1, Pp 1-13 (2021) |
| ISSN: | 2662-4435 |
| Popis: | Atmospheric methane concentrations were nearly constant between 1999 and 2006, but have been rising since by an average of ~8 ppb per year. Increases in wetland emissions, the largest natural global methane source, may be partly responsible for this rise. The scarcity of in situ atmospheric methane observations in tropical regions may be one source of large disparities between top-down and bottom-up estimates. Here we present 590 lower-troposphere vertical profiles of methane concentration from four sites across Amazonia between 2010 and 2018. We find that Amazonia emits 46.2 ± 10.3 Tg of methane per year (~8% of global emissions) with no temporal trend. Based on carbon monoxide, 17% of the sources are from biomass burning with the remainder (83%) attributable mainly to wetlands. Northwest-central Amazon emissions are nearly aseasonal, consistent with weak precipitation seasonality, while southern emissions are strongly seasonal linked to soil water seasonality. We also find a distinct east-west contrast with large fluxes in the northeast, the cause of which is currently unclear. Wetlands dominate methane emissions in Amazonia, with the largest emissions in the east but no discernible temporal trend, according to nine years of atmospheric methane observations across Amazonia. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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