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<article language="en">
	<journal>
		<journal_title>Climate of the Past Discussions</journal_title>
		<journal_url>www.clim-past-discuss.net</journal_url>
		<issn>1814-9340</issn>
		<eissn>1814-9359</eissn>
		<volume_number>2</volume_number>
		<issue_number>6</issue_number>
		<publication_year>2006</publication_year>
	</journal>
	<doi>10.5194/cpd-2-1155-2006</doi>
	<article_url>http://www.clim-past-discuss.net/2/1155/2006/</article_url>
	<abstract_html>http://www.clim-past-discuss.net/2/1155/2006/cpd-2-1155-2006.html</abstract_html>
	<fulltext_pdf>http://www.clim-past-discuss.net/2/1155/2006/cpd-2-1155-2006.pdf</fulltext_pdf>
	<start_page>1155</start_page>
	<end_page>1186</end_page>
	<publication_date>2006-11-20</publication_date>
	<article_title content_type="html">Mid-Holocene climate change in Europe: a data-model comparison</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>S. Brewer</name>
			<email>brewer@cerege.fr</email>
		</author>
		<author numeration="2" affiliations="1">
			<name>J. Guiot</name>
		</author>
		<author numeration="3" affiliations="2">
			<name>F. Torre</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">CEREGE, CNRS/Université Paul Cézanne UMR 6635, BP 80, 13545  Aix-en-Provence cedex 4, France</affiliation>
		<affiliation numeration="2" content_type="html">IMEP/Université Paul Cézanne UMR 6635, BP 80, 13545  Aix-en-Provence cedex 4, France</affiliation>
	</affiliations>
	<abstract content_type="html">We present here a comparison between the outputs of a set of 25 climate
models run for the mid-Holocene period (6 ka BP) with a set of
palaeo-climate reconstructions from over 400&amp;nbsp;fossil pollen sequences
distributed across the European continent. Three climate parameters were
available (moisture availability, temperature of the coldest month and
growing degree days), which were then grouped together using cluster
analysis to provide regions of homogenous climate change. Each model was
then investigated to see if it reproduced 1) the same directions of change and
2) the correct location of these regions. A fuzzy logic distance was used to
compare the output of the model with the data, which allowed
uncertainties from both the model and data to be taken into account. The
initial comparison showed that the models were only capable of reproducing
regions of little climate change, as the data-based reconstructions have a
much larger range of changes due to their local nature. A correction for the
model standard deviation was then applied to allow the comparison to
proceed, and this second test shows that the majority of models simulate all
the observed patterns of climatic change, although most do not simulate the
observed magnitude of change. The models were then compared by distance to
data, and by the amount of correction required. The majority of the models
are grouped together both in distance and correction, suggesting that they
are becoming more consistent. A test against a set of zero anomalies (no
climate change) shows that, whilst the models are unable to reproduce the
exact patterns of change, they all produce the correct direction of change
for the mid-Holocene.</abstract>
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</article>

