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| Titel |
Derivation and analysis of a high-resolution estimate of global permafrost zonation |
| VerfasserIn |
S. Gruber |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1994-0416
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| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 6, no. 1 ; Nr. 6, no. 1 (2012-02-17), S.221-233 |
| Datensatznummer |
250003387
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| Publikation (Nr.) |
 copernicus.org/tc-6-221-2012.pdf |
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| Zusammenfassung |
| Permafrost underlies much of Earth's surface and interacts with
climate, eco-systems and human systems. It is a complex phenomenon
controlled by climate and (sub-) surface properties and reacts to
change with variable delay. Heterogeneity and sparse data challenge
the modeling of its spatial distribution. Currently, there is no data
set to adequately inform global studies of permafrost. The available
data set for the Northern Hemisphere is frequently used for model
evaluation, but its quality and consistency are difficult to
assess. Here, a global model of permafrost extent and dataset of permafrost
zonation are presented and discussed, extending earlier studies by
including the Southern Hemisphere, by consistent data and methods,
by attention to uncertainty and scaling. Established
relationships between air temperature and the occurrence of permafrost
are re-formulated into a model that is parametrized using published
estimates. It is run with a high-resolution (<1 km) global
elevation data and air temperatures based on the NCAR-NCEP reanalysis
and CRU TS 2.0. The resulting data provide more spatial detail and
a consistent extrapolation to remote regions, while aggregated values
resemble previous studies. The estimated uncertainties affect regional
patterns and aggregate number, and provide interesting insight. The
permafrost area, i.e. the actual surface area underlain by
permafrost, north of 60° S is estimated to be
13–18 × 106 km2 or 9–14 % of the exposed land
surface. The global permafrost area including Antarctic and sub-sea
permafrost is estimated to be 16–21 × 106 km2. The
global permafrost region, i.e. the exposed land surface below which
some permafrost can be expected, is estimated to be
22 ± 3 × 106 km2. A large proportion of this
exhibits considerable topography and spatially-discontinuous
permafrost, underscoring the importance of attention to scaling issues
and heterogeneity in large-area models. |
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