Large tundra methane burst during onset of freezing
| Autor: | Mikhail Mastepanov, Sander Houweling, Edward J. Dlugokencky, Mikkel P. Tamstorf, Charlotte Sigsgaard, Torben R. Christensen, Lena Ström |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2008 |
| Předmět: |
Meteorology
Greenland Growing season Permafrost Atmospheric sciences Methane Soil chemistry.chemical_compound Freezing Faculty of Science Metan emmisioner Arktis Grønland permafrost tundra Multidisciplinary Arctic Regions Atmosphere metan vinter zackenberg Atmospheric methane Cold Climate Tundra methane winter Zackenberg Methane emissions Arctic Greenland cryosphere permafrost tundra Arctic chemistry Wetlands Greenhouse gas Atmospheric chemistry Environmental science Seasons |
| Zdroj: | Mastepanov, M, Sigsgaard, C, Dlugokencky, E J, Houwelling, S, Ström, L, Tamstorf, M P & Christensen, T R 2008, ' Large tundra methane burst during onset of freezing ', Nature, vol. 456, pp. 628-631 . https://doi.org/10.1038/nature07464 Mastepanov, M, Sigsgaard, C, Dlugokencky, E J, Houweling, S, Ström, L, Tamstorf, M P & Christensen, T R 2008, ' Large tundra methane burst during onset of freezing ', Nature, pp. 628 . |
| DOI: | 10.1038/nature07464 |
| Popis: | Udgivelsesdato: 456 Terrestrial wetland emissions are the largest single source of the greenhouse gas methane1. Northern high-latitude wetlands contribute significantly to the overall methane emissions from wetlands, but the relative source distribution between tropical and high-latitude wetlands remains uncertain2,3. As a result, not all the observed spatial and seasonal patterns of atmospheric methane concentrations can be satisfactorily explained, particularly for high northern latitudes. For example, a late-autumn shoulder is consistently observed in the seasonal cycles of atmospheric methane at high-latitude sites4, but the sources responsible for these increased methane concentrations remain uncertain. Here we report a data set that extends hourly methane flux measurements from a high Arctic setting into the late autumn and early winter, during the onset of soil freezing. We find that emissions fall to a low steady level after the growing season but then increase significantly during the freeze-in period. The integral of emissions during the freeze-in period is approximately equal to the amount of methane emitted during the entire summer season. Three-dimensional atmospheric chemistry and transport model simulations of global atmospheric methane concentrations indicate that the observed early winter emission burst improves the agreement between the simulated seasonal cycle and atmospheric data from latitudes north of 60N. Our findings suggest that permafrost-associated freeze-in bursts of methane missions from tundra regions could be an important and so far unrecognized component of the seasonal distribution of methane emissions from high latitudes. |
| Databáze: | OpenAIRE |
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