Characterization of periglacial surfaces in the Arctic Lena Delta using satellite data and field spectrometry.

• Main Authors: Grosse, Guido, Ulrich, Mathias, Schirrmeister, Lutz
• Format: Conference Object
• Language: unknown
• Published: 2006
• Subjects: Alfred Wegener Institute; Arctic; Arctic Ocean; Climate change; lena delta; permafrost; Tundra; Siberia
• Online Access: https://epic.awi.de/id/eprint/15687/; https://hdl.handle.net/10013/epic.25785

The Lena Delta in northern Siberia, covering about 32 000 km2, is the largest delta in the Arctic. It consists of complex geological and geomorphological units incorporating Holocene deltaic deposits, remains of a Late Pleistocene accumulation plain, and several fluvial terrace levels. This polar ecosystem is dominated by polygonal tundra wetlands and features a wide variety of fluvial, ecological, and permafrost-related processes which are investigated by ongoing German-Russian research co-operations since several years.A major focus of the German research by the Alfred Wegener Institute for Polar and Marine Research (AWI) in the Lena Delta is the quantification of carbon budgets and carbon release to the atmosphere and Arctic Ocean related to permafrost and periglacial processes. Tundra wetlands, which are highly sensitive to climate change, are considered major constituents of the global carbon cycle.Since climate models predict outstanding changes in a warming Arctic, considerable impacts on these wetlands are expected. An important step for the quantification of carbon budgets in tundra wetlands and regions of permafrost degradation is the upscaling of local field measurements and field knowledge with remote sensing methods. The generation of such remotely sensed baseline datasets is a precondition for understanding and quantifying present processes and the assessment of possible future changes with change detection approaches. A major achievement for these investigations in the Lena Delta was the earlier generation of a Landsat-7 ETM+ land cover classification of tundra surfaces and vegetation units. The resulting land cover map, covering the entire delta, is based on 10 land cover classes derived from field knowledge and heterogeneously distributed field data.In our approach we focused on the detailed characterization of the surface properties in small key sites of the Lena Delta: Samoylov Island in the central delta and Turakh-Sise Island in the western delta. We conducted field spectrometer measurements ...