263-6 Understanding the Arctic's Dynamic Zone: Pedogenic Process, Active Layer Thickening and a Changing Thermal Regime On Herschel Island, Yukon Territory.



Tuesday, October 18, 2011
Henry Gonzalez Convention Center, Hall C, Street Level

ABSTRACT WITHDRAWN

The surface layer that freezes and thaws seasonally in polar environments is referred to as the active layer. In the role of interface between the permafrost and the atmosphere, the active layer controls the exchange of heat and material between these two environments (French, 2008). As the Arctic is one of the fastest changing regions on our planet (IPCC, 2007), there is considerable pressure to determine more precisely the nature of these changes and evaluate their potential impact on this environment. Active layer thickening and thermokarst are frequently cited as early signs of global warming. This is because they help regulate permafrost instability, which, if unchecked, can lead to important geomorphic modifications of the ground surface and hydrological regimes (Couture & Pollard, 2007). These, in turn, may result in increases in the fluxes of greenhouse gases to the atmosphere. The overarching objective of this research is to characterize the relationship between pedogenic and geomorphic processes, and the thermal regime functioning within the active layer on Herschel Island, Yukon Territory. This research assesses rates of change for processes related to pedogenesis and weathering. Preliminary observations of soil profiles from natural exposures show evidence of strong leaching of soluble cations, suggesting relatively rapid rates of weathering and advancement of pedogenic processes. The results of this research, when combined with microclimatic data, will provide an essential foundation for understanding the effects of active layer thickening on pedogenic processes during a period of global climate warming.

Anisimov, O.A., D.G. Vaughan, T.V. Callaghan, C. Furgal, H. Marchant, T.D. Prowse, H. Vilhjálmsson and J.E. Walsh, 2007: Polar regions (Arctic and Antarctic). Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, 653-685.

Couture, N.J. and Pollard, W.H., (2007) Modelling geomorphic response of a high Arctic polar desert to climatic change. Climatic Change, DOI 10.1007/s10584-007-9309-5

French, H.M. 1976. The Periglacial Environment. Longman, New York, pp. 309.

See more from this Division: S05 Pedology
See more from this Session: General Pedology: II (Includes Graduate Student Competition)