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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACPD</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics Discussions</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACPD</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7375</issn>
<publisher><publisher-name>Copernicus GmbH</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acpd-10-12341-2010</article-id>
<title-group>
<article-title>Illustrating the benefit of using hourly monitoring data on secondary inorganic aerosol and its precursors for model evaluation</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Schaap</surname>
<given-names>M.</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>Otjes</surname>
<given-names>R. P.</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>Weijers</surname>
<given-names>E. P.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>TNO, Business unit Environment, Health and Safety, P.O. Box 80015, 3508 TA Utrecht, The Netherlands</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Energy Research Centre of the Netherlands (ECN), P.O. Box 1, 1755 LE Petten, The Netherlands</addr-line>
</aff>
<pub-date pub-type="epub">
<day>10</day>
<month>05</month>
<year>2010</year>
</pub-date>
<volume>10</volume>
<issue>5</issue>
<fpage>12341</fpage>
<lpage>12370</lpage>
<permissions>
<license xlink:type="simple">
<license-p>This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</license-p>
</license>
</permissions>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/10/12341/2010/acpd-10-12341-2010.html">This article is available from http://www.atmos-chem-phys-discuss.net/10/12341/2010/acpd-10-12341-2010.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/10/12341/2010/acpd-10-12341-2010.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/10/12341/2010/acpd-10-12341-2010.pdf</self-uri>
<abstract>
<p>Secondary inorganic aerosol, most notably ammonium nitrate and ammonium
sulphate, is an important contributor to ambient particulate mass and
provides a means for long range transport of acidifying components. The
modelling of the formation and fate of these components is challenging.
Especially, the formation of the semi-volatile ammonium nitrate is strongly
dependent on ambient conditions and the precursor concentrations. For the
first time an hourly artefact free data set from the MARGA instrument is
available for the period of a full year (1 August 2007 to 1 August 2008) at
Cabauw, the Netherlands. This data set is used to verify the results of the
LOTOS-EUROS model. The comparison showed that the model underestimates the
SIA levels. Closer inspection revealed that base line values appear well
estimated for ammonium and sulphate and that the underestimation
predominantly takes place at the peak concentrations. For nitrate the
variability towards high concentrations is much better captured, however, a
systematic relative underestimation was found. The model is able to reproduce
many features of the intra-day variability observed for SIA. Although the
model captures the seasonal and average diurnal variation of the SIA
components, the modelled variability for the nitrate precursor gas nitric
acid is much too large. It was found that the thermodynamic equilibrium
module produces a too stable ammonium nitrate in winter and during night time
in summer, whereas during the daytime in summer it is too unstable. We
recommend to improve the model by verification of the equilibrium module,
inclusion of coarse mode nitrate and to address the processes concerning SIA
formation combined with a detailed analysis of the data set at hand. The
benefit of the hourly data with both particulate and gas phase concentrations
is illustrated and a continuation of these measurements may prove to be very
useful in future model evaluation and improvement studies. Based on our
findings we propose to implement a monitoring strategy using three levels of
detail within the Netherlands.</p>
</abstract>
<counts><page-count count="30"/></counts>
</article-meta>
</front>
<body/>
<back>
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