The Cryosphere Discussions www.the-cryosphere-discuss.net 1994-0432 1994-0440 3 3 2009 10.5194/tcd-3-765-2009 http://www.the-cryosphere-discuss.net/3/765/2009/ http://www.the-cryosphere-discuss.net/3/765/2009/tcd-3-765-2009.html http://www.the-cryosphere-discuss.net/3/765/2009/tcd-3-765-2009.pdf 765 804 2009-09-17 A comparison of different methods of evaluating glacier response characteristics: application to glacier AX010, Nepal Himalaya S. Adhikari adhikars@ucalgary.ca S. J. Marshall P. Huybrechts Department of Geography, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada Earth System Sciences and Department of Geography, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Himalayan glaciers are considered to be amongst the most sensitive glaciers to climate change. However, the response behaviour of these glaciers is not well understood. Here we use several approaches to estimate characteristic timescales of glacier AX010, a small valley glacier in the Nepal Himalaya, as a measure of glacier sensitivity. Assuming that temperature solely defines the mass budget, glacier AX010 waits for about 8 yr (reaction time) to exhibit its initial terminus response to changing climate. On the other hand, it takes between 29–56 yr (volume response time) and 37–70 yr (length response time) to adjust its volume and length following the changes in mass balance conditions, respectively. A numerical ice-flow model, the only method that yields both length and volume response time, confirms that a glacier takes longer to adjust its length than its volume. Adhikari, S. and Huybrechts, P.: Numerical modelling of historical front variations and the 21st century evolution of Glacier AX010, Nepal Himalaya, Ann. Glaciol., 50(52), 27–34, 2009. 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