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<article language="en">
	<journal>
		<journal_title>Atmospheric Chemistry and Physics Discussions</journal_title>
		<journal_url>www.atmos-chem-phys-discuss.net</journal_url>
		<issn>1680-7367</issn>
		<eissn>1680-7375</eissn>
		<volume_number>8</volume_number>
		<issue_number>6</issue_number>
		<publication_year>2008</publication_year>
	</journal>
	<doi>10.5194/acpd-8-21037-2008</doi>
	<article_url>http://www.atmos-chem-phys-discuss.net/8/21037/2008/</article_url>
	<abstract_html>http://www.atmos-chem-phys-discuss.net/8/21037/2008/acpd-8-21037-2008.html</abstract_html>
	<fulltext_pdf>http://www.atmos-chem-phys-discuss.net/8/21037/2008/acpd-8-21037-2008.pdf</fulltext_pdf>
	<start_page>21037</start_page>
	<end_page>21088</end_page>
	<publication_date>2008-12-16</publication_date>
	<article_title content_type="html">The impact of weather and atmospheric circulation on O&lt;sub&gt;3&lt;/sub&gt; and  PM&lt;sub&gt;10&lt;/sub&gt; levels at a mid-latitude site</article_title>
	<authors>
		<author numeration="1" affiliations="1,2">
			<name>M. Demuzere</name>
			<email>matthias.demuzere@ees.kuleuven.be</email>
		</author>
		<author numeration="2" affiliations="2">
			<name>R. M. Trigo</name>
		</author>
		<author numeration="3" affiliations="3">
			<name>J. Vila-Guerau de Arellano</name>
		</author>
		<author numeration="4" affiliations="1">
			<name>N. P. M. van Lipzig</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Earth and environmental Sciences, Celestijnenlaan 200E, 3001 Heverlee  (Leuven), Katholieke Universiteit Leuven, Belgium</affiliation>
		<affiliation numeration="2" content_type="html">Department of Geophysics, University of Lisbon, Centro de  Geofísica da Universidade de Lisboa  Fac. Ciencias, Campo Grande, Ed. C8, Piso 6, 1749-016 LISBOA, Portugal</affiliation>
		<affiliation numeration="3" content_type="html">Meteorology and Air Quality Section, Wageningen University,  Droevendaalsesteeg 4, P.O. Box 47, 6700 AA Wageningen, The Netherlands</affiliation>
	</affiliations>
	<abstract content_type="html">In spite of the strict EU regulations, concentrations of surface ozone and
PM&lt;sub&gt;10&lt;/sub&gt; often exceed the pollution standards for The Netherlands and
Europe. Their concentrations are controlled by (precursor) emissions, social
and economic developments and a complex combination of meteorological
actors. This study tackles the latter, and provides insight in the
meteorological processes that play a role in O&lt;sub&gt;3&lt;/sub&gt; and PM&lt;sub&gt;10&lt;/sub&gt; 
levels in Cabauw (The Netherlands). The relations between meteorological
actors and air quality are studied on a~local scale based on observations from
Cabauw and are determined by a comprehensive correlation analysis and
a multiple regression (MLR) analysis in 2 modes, with and without air quality
variables as predictors. Furthermore, the objective Lamb Weather Type (WT)
approach based on ECMWF (European Center for Medium-range Weather Forecasting)
operational data is used to assess the influence of the large-scale
circulation on air quality. Keeping in mind its future use in downscaling
future climate scenarios for air quality purposes, special emphasis is given
to an appropriate selection of the regressor variables readily available from
operational meteorological forecasts or OAGCMs (Ocean-Atmosphere coupled
General Circulation Models). The regression models perform satisfactory for
both O&lt;sub&gt;3&lt;/sub&gt; and PM&lt;sub&gt;10&lt;/sub&gt;, with an increased performance when
including previous days air quality information. The lamb weather types show
a seasonal distinct pattern for high (low) episodes of average O&lt;sub&gt;3&lt;/sub&gt; and
PM&lt;sub&gt;10&lt;/sub&gt; concentrations, and these are clear related with the
meteorology-air quality correlation analysis. Although using a circulation
type approach can bring some interesting physical relations forward, our
analysis reveals the circulation method is limited in terms of short-term air
quality forecast for both  O&lt;sub&gt;3&lt;/sub&gt; and PM&lt;sub&gt;10&lt;/sub&gt;. In summary, it is
concluded that the use of a regression model is more promising for short-term
downscaling from climate scenarios than the use of a weather type
classification approach.</abstract>
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