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<front>
<journal-meta>
<journal-id journal-id-type="publisher">TC</journal-id>
<journal-title-group>
<journal-title>The Cryosphere</journal-title>
<abbrev-journal-title abbrev-type="publisher">TC</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">The Cryosphere</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1994-0424</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/tc-6-221-2012</article-id>
<title-group>
<article-title>Derivation and analysis of a high-resolution estimate of global permafrost zonation</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Gruber</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Glaciology, Geomorphodynamics and Geochronology, Department of Geography, University of Zurich, Switzerland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>17</day>
<month>02</month>
<year>2012</year>
</pub-date>
<volume>6</volume>
<issue>1</issue>
<fpage>221</fpage>
<lpage>233</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2012 S. Gruber</copyright-statement>
<copyright-year>2012</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/3.0/">https://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://tc.copernicus.org/articles/6/221/2012/tc-6-221-2012.html">This article is available from https://tc.copernicus.org/articles/6/221/2012/tc-6-221-2012.html</self-uri>
<self-uri xlink:href="https://tc.copernicus.org/articles/6/221/2012/tc-6-221-2012.pdf">The full text article is available as a PDF file from https://tc.copernicus.org/articles/6/221/2012/tc-6-221-2012.pdf</self-uri>
<abstract>
<p>Permafrost underlies much of Earth&apos;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 (&lt;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&amp;deg; S is estimated to be
      13–18 × 10&lt;sup&gt;6&lt;/sup&gt; km&lt;sup&gt;2&lt;/sup&gt; or 9–14 % of the exposed land
      surface. The global permafrost area including Antarctic and sub-sea
      permafrost is estimated to be 16–21 × 10&lt;sup&gt;6&lt;/sup&gt; km&lt;sup&gt;2&lt;/sup&gt;. The
      global permafrost region, i.e. the exposed land surface below which
      some permafrost can be expected, is estimated to be
      22 ± 3 × 10&lt;sup&gt;6&lt;/sup&gt; km&lt;sup&gt;2&lt;/sup&gt;. 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.</p>
</abstract>
<counts><page-count count="13"/></counts>
</article-meta>
</front>
<body/>
<back>
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