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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>14</volume_number>
		<issue_number>2</issue_number>
		<publication_year>2010</publication_year>
	</journal>
	<doi>10.5194/hess-14-271-2010</doi>
	<article_url>http://www.hydrol-earth-syst-sci.net/14/271/2010/</article_url>
	<abstract_html>http://www.hydrol-earth-syst-sci.net/14/271/2010/hess-14-271-2010.html</abstract_html>
	<fulltext_pdf>http://www.hydrol-earth-syst-sci.net/14/271/2010/hess-14-271-2010.pdf</fulltext_pdf>
	<start_page>271</start_page>
	<end_page>277</end_page>
	<publication_date>2010-02-12</publication_date>
	<article_title content_type="html">Technical Note: Comparing and ranking soil drought indices performance over Europe, through remote-sensing of vegetation</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>E. Peled</name>
		</author>
		<author numeration="2" affiliations="2">
			<name>E. Dutra</name>
		</author>
		<author numeration="3" affiliations="2,3">
			<name>P. Viterbo</name>
		</author>
		<author numeration="4" affiliations="1">
			<name>A. Angert</name>
			<email>angert@huji.ac.il</email>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">The Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel</affiliation>
		<affiliation numeration="2" content_type="html">IDL, CGUL, University of Lisbon, Lisbon, Portugal</affiliation>
		<affiliation numeration="3" content_type="html">Institute of Meteorology, Lisbon, Portugal</affiliation>
	</affiliations>
	<abstract content_type="html">In the past years there have been many attempts to produce and improve
global soil-moisture datasets and drought indices. However, comparing and
validating these various datasets is not straightforward. Here, interannual
variations in drought indices are compared to interannual changes in
vegetation, as captured by NDVI. By comparing the correlations of the
different indices with NDVI we evaluated which drought index describes most
realistically the actual changes in vegetation. Strong correlation between
NDVI and the drought indices were found in areas that are classified as warm
temperate climate with hot or warm dry summers. In these areas we ranked the
PDSI, PSDI-SC, SPI3, and NSM indices, based on the interannual correlation
with NDVI, and found that NSM outperformed the rest. Using this best
performing index, and the ICA (Independent Component Analysis) technique, we
analyzed the response of vegetation to temperature and soil-moisture
stresses over Europe.</abstract>
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</article>

