In:
Earth System Science Data, Copernicus GmbH, Vol. 10, No. 4 ( 2018-10-10), p. 1807-1827
Abstract:
Abstract. Knowledge about the coverage and characteristics of glaciers in High Mountain
Asia (HMA) is still incomplete and heterogeneous. However, several
applications, such as modelling of past or future glacier development,
run-off, or glacier volume, rely on the existence and accessibility of
complete datasets. In particular, precise outlines of glacier extent are
required to spatially constrain glacier-specific calculations such as length,
area, and volume changes or flow velocities. As a contribution to the
Randolph Glacier Inventory (RGI) and the Global Land Ice Measurements from
Space (GLIMS) glacier database, we have produced a homogeneous inventory of
the Pamir and the Karakoram mountain ranges using 28 Landsat TM and ETM+
scenes acquired around the year 2000. We applied a standardized method of
automated digital glacier mapping and manual correction using coherence
images from the Advanced Land Observing Satellite 1 (ALOS-1) Phased Array
type L-band Synthetic Aperture Radar 1 (PALSAR-1)
as an additional source of information; we then (i) separated the glacier
complexes into individual glaciers using drainage divides derived by
watershed analysis from the ASTER global digital elevation model version 2
(GDEM2) and (ii) separately delineated all debris-covered areas. Assessment
of uncertainties was performed for debris-covered and clean-ice glacier parts
using the buffer method and independent multiple digitizing of three glaciers
representing key challenges such as shadows and debris cover. Indeed, along
with seasonal snow at high elevations, shadow and debris cover represent the
largest uncertainties in our final dataset. In total, we mapped more than
27 800 glaciers 〉0.02 km2 covering an area of 35 520±1948 km2 and an elevation range from 2260 to 8600 m. Regional median
glacier elevations vary from 4150 m (Pamir Alai) to almost
5400 m (Karakoram), which is largely due to differences in temperature and
precipitation. Supraglacial debris covers an area of 3587±662 km2,
i.e. 10 % of the total glacierized area. Larger glaciers have a higher
share in debris-covered area (up to 〉20 %), making it an important
factor to be considered in subsequent applications
(https://doi.org/10.1594/PANGAEA.894707).
Type of Medium:
Online Resource
ISSN:
1866-3516
DOI:
10.5194/essd-10-1807-2018
DOI:
10.5194/essd-10-1807-2018-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2018
detail.hit.zdb_id:
2475469-9
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