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<front>
<journal-meta>
<journal-id journal-id-type="publisher">HESS</journal-id>
<journal-title-group>
<journal-title>Hydrology and Earth System Sciences</journal-title>
<abbrev-journal-title abbrev-type="publisher">HESS</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Hydrol. Earth Syst. Sci.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1607-7938</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/hess-16-1349-2012</article-id>
<title-group>
<article-title>Spatial horizontal correlation characteristics in the land data assimilation of soil moisture</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Han</surname>
<given-names>X.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Li</surname>
<given-names>X.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Hendricks Franssen</surname>
<given-names>H. J.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Vereecken</surname>
<given-names>H.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Montzka</surname>
<given-names>C.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Gansu, 730000, China</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Forschungszentrum Jülich, Agrosphere (IBG 3), Leo-Brandt-Strasse, 52425 Jülich, Germany</addr-line>
</aff>
<pub-date pub-type="epub">
<day>10</day>
<month>05</month>
<year>2012</year>
</pub-date>
<volume>16</volume>
<issue>5</issue>
<fpage>1349</fpage>
<lpage>1363</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2012 X. Han et al.</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://hess.copernicus.org/articles/16/1349/2012/hess-16-1349-2012.html">This article is available from https://hess.copernicus.org/articles/16/1349/2012/hess-16-1349-2012.html</self-uri>
<self-uri xlink:href="https://hess.copernicus.org/articles/16/1349/2012/hess-16-1349-2012.pdf">The full text article is available as a PDF file from https://hess.copernicus.org/articles/16/1349/2012/hess-16-1349-2012.pdf</self-uri>
<abstract>
<p>Remote sensing images deliver important information about soil moisture, but
often cover only part of an area, for example due to the presence of clouds
or vegetation. This paper examines the potential of incorporating the
spatial horizontal correlation characteristics of surface soil moisture
observations in land data assimilation in order to obtain improved estimates
of soil moisture at uncovered grid cells (i.e. grid cells without
observations). Observing system simulation experiments were carried out to
assimilate the synthetic surface soil moisture observations into the
Community Land Model for the Babaohe River Basin in northwestern China. The
estimation of soil moisture at the uncovered grid cells was improved when
information about surrounding observations and their spatial correlation
structure was included. Including an increasing number of observations for
covered and uncovered grid cells in the assimilation procedure led to a
better prediction of soil moisture with an upper limit of five observations.
A further increase of the number of observations did not further improve the
results for this specific case. High observational coverage resulted in a
better assimilation performance, depending also on the spatial distribution
of observation data. In summary, the spatial horizontal correlation
structure of soil moisture was found to be helpful for improving the surface
soil moisture data characterization, especially for uncovered grid cells.</p>
</abstract>
<counts><page-count count="15"/></counts>
</article-meta>
</front>
<body/>
<back>
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