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<article language="en">
	<journal>
		<journal_title>Hydrology and Earth System Sciences</journal_title>
		<journal_url>www.hydrol-earth-syst-sci.net</journal_url>
		<issn>1027-5606</issn>
		<eissn>1607-7938</eissn>
		<volume_number>13</volume_number>
		<issue_number>3</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/hess-13-343-2009</doi>
	<article_url>http://www.hydrol-earth-syst-sci.net/13/343/2009/</article_url>
	<abstract_html>http://www.hydrol-earth-syst-sci.net/13/343/2009/hess-13-343-2009.html</abstract_html>
	<fulltext_pdf>http://www.hydrol-earth-syst-sci.net/13/343/2009/hess-13-343-2009.pdf</fulltext_pdf>
	<start_page>343</start_page>
	<end_page>356</end_page>
	<publication_date>2009-03-13</publication_date>
	<article_title content_type="html">Soil moisture retrieval through a merging of multi-temporal  L-band SAR data and hydrologic modelling</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>F. Mattia</name>
			<email>F.Mattia@ba.issia.cnr.it</email>
		</author>
		<author numeration="2" affiliations="1">
			<name>G. Satalino</name>
		</author>
		<author numeration="3" affiliations="2">
			<name>V. R. N. Pauwels</name>
		</author>
		<author numeration="4" affiliations="3">
			<name>A. Loew</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Consiglio Nazionale delle Ricerche, Istituto di Studi sui Sistemi Intelligenti per l&apos;Automazione (ISSIA), Bari, Italy</affiliation>
		<affiliation numeration="2" content_type="html">Ghent University, Laboratory of Hydrology and Water  Management (LHWM), Ghent, Belgium</affiliation>
		<affiliation numeration="3" content_type="html">Max-Planck-Institute for Meteorology, The Land in the Earth System,  Hamburg, Germany</affiliation>
	</affiliations>
	<abstract content_type="html">The objective of the study is to investigate the potential of
retrieving superficial soil moisture content (&lt;i&gt;m&lt;sub&gt;v&lt;/sub&gt;&lt;/i&gt;) from
multi-temporal L-band synthetic aperture radar (SAR) data and
hydrologic modelling. The study focuses on assessing the
performances of an L-band SAR retrieval algorithm intended for
agricultural areas and for watershed spatial scales (e.g. from 100
to 10 000 km&lt;sup&gt;2&lt;/sup&gt;). The algorithm transforms temporal series of
L-band SAR data into soil moisture contents by using a constrained
minimization technique integrating a priori information on
soil parameters. The rationale of the approach consists of
exploiting soil moisture predictions, obtained at coarse spatial
resolution (e.g. 15–30 km&lt;sup&gt;2&lt;/sup&gt;) by point scale hydrologic models
(or by simplified estimators), as a priori information for
the SAR retrieval algorithm that provides soil moisture maps at
high spatial resolution (e.g. 0.01 km&lt;sup&gt;2&lt;/sup&gt;). In the present form,
the retrieval algorithm applies to cereal fields and has been
assessed on simulated and experimental data. The latter were
acquired by the airborne E-SAR system during the AgriSAR campaign
carried out over the Demmin site (Northern Germany) in 2006.
Results indicate that the retrieval algorithm always improves the
a priori information on soil moisture content though the
improvement may be marginal when the accuracy of prior &lt;i&gt;m&lt;sub&gt;v&lt;/sub&gt;&lt;/i&gt;
estimates is better than 5%.</abstract>
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