CGRG Bibliography of Canadian Geomorphology
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Author : Arendt, A.A.; Echelmeyer, K.A.; Harrison, W.D.; Lingle, C.S.; Valentine, V.B.; and Zirnheld, S.L.
Date : 2003.
Title : The contribution of Alaska glaciers to rising sea level.
Publication : Extreme Events: Understanding Perturbations to the Physical and Biological Environment. Program and Abstracts. 54th Arctic Science Conference, 21-24 September 2003 Westmark Hotel and Convention Center, Fairbanks, Alaska.
Issue :
Page(s) : 194.
Abstract
We have used airborne laser altimetry to measure surface elevation profiles of almost 100 glaciers in Alaska and northwestern Canada. To date, 72 of these glacier profiles have been compared to USGS maps to calculate volume changes from the mid-1950s to the mid-1990s. The average thickness change of these glaciers was -0.5 m a-1. Extrapolation to all glaciers in Alaska yields an estimated contribution to a rise in sea level of 0.14±0.04 mm a-1, which is about 8% of the mean global sea level rise (1.5 mm a-1) during that time period. Repeat profiles of 28 glaciers between the mid-1990s and 2000/01 suggest that the thinning rate has almost doubled in recent years. Our estimates represent the largest glaciological contribution to rising sea level yet measured. Our preliminary analyses of Alaska climate data show that surface temperatures across Alaska have increased during the past 50 years, with the greatest increase (+0.9oC) occurring during the winter. Summer temperatures have increased by 0.4oC, a value slightly less than that which would explain the measured glacier changes, as determined from a simple mass balance model. Long-term snow depth measurements show a weak increasing snowfall trend, but upper air data show an increase in the height of the mean freezing level, suggesting more precipitation may be falling as rain instead of snow.
Bibliography of Canadian Geomorphology