Multi-decadal mass loss of glaciers in the Everest area (Nepal Himalaya) derived from stereo imagery 1Institut für Kartographie, Technische Universität Dresden, Germany
20 Apr 2011
2The University Centre in Svalbard, Norway
3Geographisches Institut, Universität Zürich, Switzerland
4School of Geography and Geosciences, University of St Andrews, UK
Received: 01 Dec 2010 – Published in The Cryosphere Discuss.: 20 Dec 2010 Abstract. Mass loss of Himalayan glaciers has wide-ranging consequences such as
changing runoff distribution, sea level rise and an increasing risk of
glacial lake outburst floods (GLOFs). The assessment of the regional and
global impact of glacier changes in the Himalaya is, however, hampered by a
lack of mass balance data for most of the range. Multi-temporal digital
terrain models (DTMs) allow glacier mass balance to be calculated. Here, we present a time series of mass
changes for ten glaciers covering an area of about 50 km2 south and
west of Mt. Everest, Nepal, using stereo Corona spy imagery (years 1962 and
1970), aerial images and recent high resolution satellite data (Cartosat-1).
This is the longest time series of mass changes in the Himalaya. We reveal
that the glaciers have been significantly losing mass since at least 1970,
despite thick debris cover. The specific mass loss for 1970–2007 is 0.32 ± 0.08 m w.e. a−1, however, not higher than the global average.
Comparisons of the recent DTMs with earlier time periods indicate an
accelerated mass loss. This is, however, hardly statistically significant
due to high uncertainty, especially of the lower resolution ASTER DTM. The
characteristics of surface lowering can be explained by spatial variations
of glacier velocity, the thickness of the debris-cover, and ice melt due to
exposed ice cliffs and ponds.
Revised: 28 Mar 2011 – Accepted: 30 Mar 2011 – Published: 20 Apr 2011
Citation: Bolch, T., Pieczonka, T., and Benn, D. I.: Multi-decadal mass loss of glaciers in the Everest area (Nepal Himalaya) derived from stereo imagery, The Cryosphere, 5, 349-358, doi:10.5194/tc-5-349-2011, 2011.