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A. Bartsch, C. Pathe, W. Wagner, K. Scipal:
"Detection of permanent open water surfaces in central Siberia with ENVISAT ASAR wide swath data with special emphasis on the estimation of methane fluxes from tundra wetlands.";
Hydrology Research, 39 (2008), 2; S. 89 - 100.

Permanent water bodies not only store dissolved CO2 but are essential for the maintenance of
wetlands in their proximity. From the viewpoint of greenhouse gas (GHG) accounting wetland
functions comprise sequestration of carbon under anaerobic conditions and methane release. The
investigated area in central Siberia covers boreal and sub-arctic environments. Small inundated
basins are abundant on the sub-arctic Taymir lowlands but also in parts of severe boreal climate
where permafrost ice content is high and feature important freshwater ecosystems. Satellite
radar imagery (ENVISAT ScanSAR), acquired in summer 2003 and 2004, has been used to derive
open water surfaces with 150m resolution, covering an area of approximately 3Mkm2. The open
water surface maps were derived using a simple threshold-based classification method. The
results were assessed with Russian forest inventory data, which includes detailed information
about water bodies. The resulting classification has been further used to estimate the extent of
tundra wetlands and to determine their importance for methane emissions. Tundra wetlands
cover 7% (400 000km2) of the study region and methane emissions from hydromorphic soils are
estimated to be 45 000 t d21 for the Taymir peninsula.

remote sensing, ScanSAR, Siberia, Taymir, tundra, wetland

http://dx.doi.org/10.2166/nh.2008.041