<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd">
<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" article-type="research-article" dtd-version="3.0" xml:lang="en">
<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-12-10995-2012</article-id>
<title-group>
<article-title>Trends of particulate matter (PM&lt;sub&gt;2.5&lt;/sub&gt;) and chemical composition at a regional background site in the Western Mediterranean over the last nine years (2002–2010)</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Cusack</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Alastuey</surname>
<given-names>A.</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>Pérez</surname>
<given-names>N.</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>Pey</surname>
<given-names>J.</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>Querol</surname>
<given-names>X.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Institute of Environmental Assessment and Water Research, IDǼA, CSIC, C/ Jordi Girona, 18-26, 08034, Barcelona, Spain</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Institute of Environmental Science and Technology (ICTA), Universitat Autónoma de Barcelona, 08193, Bellaterra, Barcelona, Spain</addr-line>
</aff>
<pub-date pub-type="epub">
<day>27</day>
<month>04</month>
<year>2012</year>
</pub-date>
<volume>12</volume>
<issue>4</issue>
<fpage>10995</fpage>
<lpage>11033</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/12/10995/2012/acpd-12-10995-2012.html">This article is available from http://www.atmos-chem-phys-discuss.net/12/10995/2012/acpd-12-10995-2012.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/12/10995/2012/acpd-12-10995-2012.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/12/10995/2012/acpd-12-10995-2012.pdf</self-uri>
<abstract>
<p>The time variability and long term trends of PM&lt;sub&gt;2.5&lt;/sub&gt; (particulate matter
of diameter &lt;2.5 μm) at various regional background (RB) sites across
Europe are studied and interpreted in this work. Long-term trends of
PM&lt;sub&gt;2.5&lt;/sub&gt; concentrations are relatively scarce across Europe, with few
studies outlining the changes measured in PM&lt;sub&gt;2.5&lt;/sub&gt; concentrations over a
significant period of time. To this end, data on mean annual levels of
PM&lt;sub&gt;2.5&lt;/sub&gt; measured at Montseny (MSY, North East Spain) and various RB sites
in Spain and Europe are evaluated and compared, and subsequently analysed
for statistically significant trends. The MSY site registered higher average
PM&lt;sub&gt;2.5&lt;/sub&gt; levels than those measured at a selection of other RB sites
across Spain, Portugal, Germany and Scandinavia, but lower than those
measured in Switzerland, Italy and Austria.
&lt;br&gt;&lt;br&gt;
Reductions in PM&lt;sub&gt;2.5&lt;/sub&gt; were observed across all stations in Spain and
Europe to varying degrees. MSY underwent a statistically significant
reduction since measurements began, indicating a year-on-year gradual
decrease (−3.7 μg m&lt;sup&gt;−3&lt;/sup&gt;, calculated from the final year of
data compared to the mean). Similar trends were observed in other RB sites
across Spain (−1.9 μg m&lt;sup&gt;−3&lt;/sup&gt;). Reductions recorded in
PM&lt;sub&gt;2.5&lt;/sub&gt; across Europe were varied, with many experiencing gradual,
year-on-year decreases (−1.8 μg m&lt;sup&gt;−3&lt;/sup&gt;). These reductions have
been attributed to various causes: the introduction and implementation of
pollution abatement strategies in EU member states, the effect of the current
economic crisis on emissions of PM&lt;sub&gt;2.5&lt;/sub&gt; and the influence of anomalous
meteorology observed during the winters of 2009 and 2010. The North Atlantic
Oscillation (NAO), a large scale meteorological phenomenon most prevalent
during winter, was observed to influence the frequency of Saharan dust
intrusions across the Iberian Peninsula.
&lt;br&gt;&lt;br&gt;
Chemical composition of PM&lt;sub&gt;2.5&lt;/sub&gt; at MSY is characterised by high levels of
organic matter (OM) and sulphate, followed by crustal material, nitrate and
ammonia. Sea Spray and finally elemental carbon (EC) comprised a minor part
of the total PM&lt;sub&gt;2.5&lt;/sub&gt; mass. Statistical trend analysis was performed on
the various chemical components of PM&lt;sub&gt;2.5&lt;/sub&gt; recorded at MSY to determine
which components were accountable for the decrease in PM&lt;sub&gt;2.5&lt;/sub&gt; 
concentration. It is shown that OM underwent the largest decrease over the
time period with a statistically significant trend (−1.3 μg m&lt;sup&gt;−3&lt;/sup&gt;
of the mean), followed by sulphate (−0.8 μg m&lt;sup&gt;−3&lt;/sup&gt;), 
ammonium (−0.5 μg m&lt;sup&gt;−3&lt;/sup&gt;) and nitrate (−0.4 μg m&lt;sup&gt;−3&lt;/sup&gt;).
Conversely, sea spray, EC and crustal material reductions were found to be negligible.</p>
</abstract>
<counts><page-count count="39"/></counts>
</article-meta>
</front>
<body/>
<back>
<ref-list>
<title>References</title>
<ref id="ref1">
<label>1</label><mixed-citation publication-type="other" xlink:type="simple"> Aiken, A. C., DeCarlo, P. F., Kroll, J. H., Worsnop, D. R., Huffman, J. A., Doherty, K., Ulbrich, I. M., Mohr, C., Kimmel, J.r., Sueper, D., Zhang, Q., Sun, Y., Trimborn, A., Northway, M., Ziemann, P. J., Canagaratna, M. R., Onasch, T. B., Alfarra, R., Prévôt, A. S. H., Dommen, J., Duplissy, J., Metzger, A., Baltensperger, U., and Jimenez, J. L.: O/C and OM/OC Ratios of Primary, Secondary, and Ambient Organic Aerosols with High Resolution Time-of-Flight Aerosol Mass Spectrometry, Environ. Sci. Technol., 42, 4478–4485, 2005. </mixed-citation>
</ref>
<ref id="ref2">
<label>2</label><mixed-citation publication-type="other" xlink:type="simple"> Arruti, A., Fernández-Olmo, I., and Irabien, A.: Impact of the global economic crisis on metal levels in particulate matter (PM) at an urban area in the Cantabria Region (Northern Spain), Environ. Pollut., 159, 1129–1135, 2011. </mixed-citation>
</ref>
<ref id="ref3">
<label>3</label><mixed-citation publication-type="other" xlink:type="simple"> Barmpadimos, I., Keller, J., Oderbolz, D., Hueglin, J., and Prévôt, A. S. H.: One decade of paralled fine (PM2.5) and coarse (PM$_10$–PM$_2.5$) particulate matter measurements in Europe: trends and variability. Atmos. Chem. Phys., 12, 3189–3203, doi:10.5194/acp-12-3189-2012, 2012. </mixed-citation>
</ref>
<ref id="ref4">
<label>4</label><mixed-citation publication-type="other" xlink:type="simple"> Bruno, J., Pon, J., and Russi, D.: Report on Air Quality and Health: the cost of improvement of air quality (in Catalan). Generalitat de Catalunya, Departament de Medi Ambient i Habitatge, December 2007. </mixed-citation>
</ref>
<ref id="ref5">
<label>5</label><mixed-citation publication-type="other" xlink:type="simple"> Gangoiti, G., Millán, M. M., Salvador, R., and Mantilla, E.: Long range transport and re-circulation of pollutants in the Western Mediterranean during the RECAPMA-Project, Atmos. Environ., 35, 6267–6276, 2001. </mixed-citation>
</ref>
<ref id="ref6">
<label>6</label><mixed-citation publication-type="other" xlink:type="simple"> Ge, X., Wexler, A. S., and Clegg, S. L.: Atmospheric amines-Part 1. A review, Atmos. Environ., 45, 524–546, 2011. </mixed-citation>
</ref>
<ref id="ref7">
<label>7</label><mixed-citation publication-type="other" xlink:type="simple"> Gilbert, R. O.: Statistical methods for environmental pollution monitoring. Van Nostrand Reinhold, New York, USA, 1987. </mixed-citation>
</ref>
<ref id="ref8">
<label>8</label><mixed-citation publication-type="other" xlink:type="simple"> Harrison, R. M. and Pio, C.: Size differentiated composition of inorganic aerosol of both marine and continental polluted origin, Atmos. Environ., 17, 1733–1738, 1983. </mixed-citation>
</ref>
<ref id="ref9">
<label>9</label><mixed-citation publication-type="other" xlink:type="simple"> Querol, X., Alastuey, A., Viana, M. M., Rodríguez, S., Artíñano, B., Salvador, P., Santos, S. G. D., Patier, R. F., Ruiz, C. R., Rosa, J. D. L., Campa, A. S. D. L., Menedez, M., and Gil, J. I.: Speciation and origin of PM$_10$ and PM2.5 in Spain, J. Aerosol Sci., 35, 1151–1172, 2004. </mixed-citation>
</ref>
<ref id="ref10">
<label>10</label><mixed-citation publication-type="other" xlink:type="simple"> Hurrell, J., Kushnir, Y., Otterson, G., and Visbeck, M.: An overview of the north Atlantic oscillation. The North Atlantic Oscillation: climate significance and environmental impact. Geophys. Monogr., 134, 1–35, 2003. </mixed-citation>
</ref>
<ref id="ref11">
<label>11</label><mixed-citation publication-type="other" xlink:type="simple"> Hurrell, J. and Deser, C.: North Atlantic climate variability: the role of the North Atlantic oscillation, J. Mar. Syst., 78, 28–41, 2009. </mixed-citation>
</ref>
<ref id="ref12">
<label>12</label><mixed-citation publication-type="other" xlink:type="simple"> IPCC: Climate Change 2007: The Physical Science Basis, Contribution of Working Group I to the Fourth Assessment Report of the IPCC, ISBN~978~0521~88009-1 Hardback; 978~0521~70596-7~Paperback, 2007. </mixed-citation>
</ref>
<ref id="ref13">
<label>13</label><mixed-citation publication-type="other" xlink:type="simple"> Jorba, O., Pérez, C., Rocadenbosch, F., and Baldasano, J. K.: Cluster Analysis of 4-Day Back Trajectories Arriving in the Barcelona Area (Spain) from 1997 to 2002, J. Appl. Meteorol, 43, 887-901, 2004. </mixed-citation>
</ref>
<ref id="ref14">
<label>14</label><mixed-citation publication-type="other" xlink:type="simple"> Lyamani, H., Olmo, F. J., Foyo, I., and Alados-Arboledas, L.: Black carbon aerosols over an urban area in south-eastern Spain: Changes detected after the 2008 economic crisis, Atmos. Environ., 45, 6423–6432, 2011. </mixed-citation>
</ref>
<ref id="ref15">
<label>15</label><mixed-citation publication-type="other" xlink:type="simple"> Millán, M., Salvador, R., Mantilla, E., and Kallos, G.: Photo-oxidant dynamics in the Mediterranean basin in summer: results from European research projects, J. Geophys. Res., 102, 8811–8823, 1997. </mixed-citation>
</ref>
<ref id="ref16">
<label>16</label><mixed-citation publication-type="other" xlink:type="simple"> Minguillón, M. C., Perron, N., Querol, X., Szidat, S., Fahrni, S. M., Alastuey, A., Jimenez, J. L., Mohr, C., Ortega, A. M., Day, D. A., Lanz, V. A., Wacker, L., Reche, C., Cusack, M., Amato, F., Kiss, G., Hoffer, A., Decesari, S., Moretti, F., Hillamo, R., Teinilä, K., Seco. R., Peñuelas, J., Metzger, A., Schallhart, S., Müller, M., Hansel, A., Burkhart, J. F., Baltensperger, U., Prévôt, A. S. H.: Fossil versus contemporary sources of fine elemental and organic carbonaceous particulate matter during the DAURE campaign in Northeast Spain, Atmos. Chem. Phys., 11, 12067–12084, http://dx.doi.org/10.5194/acp-11-12067-2011doi:10.5194/acp-11-12067-2011, 2011. </mixed-citation>
</ref>
<ref id="ref17">
<label>17</label><mixed-citation publication-type="other" xlink:type="simple"> Moreno, T., Querol, X., Alastuey, A., Reche, C., Cusack, M., Amato, F., Pandolfi, M., Pey, J., Richard, A., Prévôt, A. S. H., Furger, M., and Gibbons, W.: Variations in time and space of trace metal aerosol concentrations in urban areas and their surroundings, Atmos. Chem. Phys., 11, 9415–9430, http://dx.doi.org/10.5194/acp-11-9415-2011doi:10.5194/acp-11-9415-2011, 2011. </mixed-citation>
</ref>
<ref id="ref18">
<label>18</label><mixed-citation publication-type="other" xlink:type="simple"> Moulin, D., Lambert, C. E., Dulac, F., and Dayan, U.: Control of atmospheric export of dust from North Africa by the North Atlantic Oscillation, Nature, 387, 691–694, 1997. </mixed-citation>
</ref>
<ref id="ref19">
<label>19</label><mixed-citation publication-type="other" xlink:type="simple"> Peñuelas, J., Llusia, J., and Gimeno, B. S.: Effects of ozone concentrations on biogenic volatile organic compounds emission in the Mediterranean region, Environ. Pollut., 105, 17–23, 1999. </mixed-citation>
</ref>
<ref id="ref20">
<label>20</label><mixed-citation publication-type="other" xlink:type="simple"> Pérez, C., Sicard, M., Jorba, O., Comeron, A., andBaldasano, J. K.: Summertime re-circulations of air pollutants over the north-eastern Iberian coast observed from systematic EARLINET lidar measurements in Barcelona, Atmos. Environ., 38, 3983–4000, 2004. </mixed-citation>
</ref>
<ref id="ref21">
<label>21</label><mixed-citation publication-type="other" xlink:type="simple"> Pérez, N., Pey, J., Castillo, S., Viana, M., Alastuey, A., and Querol, X.: Interpretation of the variability of levels of regional background aerosols in the Western Mediterranean. Sci. Total Environ., 407, 524–540, 2008. </mixed-citation>
</ref>
<ref id="ref22">
<label>22</label><mixed-citation publication-type="other" xlink:type="simple"> Pey, J., Pérez, N., Castillo, S., Viana, M., Moreno, T., Pandolfi, M., López-Sebastián, J.M., Alastuey, A., and Querol, X.: Geochemistry of regional background aerosols in the Western Mediterranean, Atmos. Res., 94, 422–435, 2009. </mixed-citation>
</ref>
<ref id="ref23">
<label>23</label><mixed-citation publication-type="other" xlink:type="simple"> Pey, J., Pérez, N., Querol, X., Alastuey, A., Cusack, M., and Reche, C.: Intense winter pollution episodes affecting the Western Mediterranean. Sci. Total Environ., 408, 1951–1959, 2010. </mixed-citation>
</ref>
<ref id="ref24">
<label>24</label><mixed-citation publication-type="other" xlink:type="simple"> Pope, C. A. and Dockery, D. W.: Health effects of fine particulate air pollution: lines that connect. J. Air. Waste Manage., 56, 709–742, 2006. </mixed-citation>
</ref>
<ref id="ref25">
<label>25</label><mixed-citation publication-type="other" xlink:type="simple"> Querol, X., Alastuey A., Puicercus, J. A., Mantilla, E., Ruiz, C. R., Lopez-Soler, A., Plana, F., and Artíñano, B.: Seasonal evolution of suspended particles around a coal-fired power station: particulate levels and sources. Atmos. Environ., 32, 719–731, 1998a. </mixed-citation>
</ref>
<ref id="ref26">
<label>26</label><mixed-citation publication-type="other" xlink:type="simple"> Querol, X., Alastuey A., Puicercus, J. A., Mantilla, E., Ruiz, C. R., Lopez-Soler, A., Plana, F., and Artíñano, B.: Seasonal evolution of suspended particles around a coal-fired power station: particulate levels and sources, Atmos. Environ., 32, 1963–1978, 1998b. </mixed-citation>
</ref>
<ref id="ref27">
<label>27</label><mixed-citation publication-type="other" xlink:type="simple"> Querol, X., Alastuey, A., Rodríguez, S., Plana, F., Mantilla, E., and Ruiz, C. R.: Monitoring of PM$_10$ and PM$_2.5$ around primary particulate anthropogenic emission sources, Atmos. Environ., 35, 845–858, 2001. </mixed-citation>
</ref>
<ref id="ref28">
<label>28</label><mixed-citation publication-type="other" xlink:type="simple"> Querol, X., Pey, J., Minguillón, MC., Pérez, N., Alastuey, A., and Viana, M.: PM speciation and sources in Mexico during the MILAGRO-2006 Campaign. Atmos. Chem. Phys., 8, 111–128, http://dx.doi.org/10.5194/acp-8-111-2008doi:10.5194/acp-8-111-2008, 2008. </mixed-citation>
</ref>
<ref id="ref29">
<label>29</label><mixed-citation publication-type="other" xlink:type="simple"> Querol, X., Alastuey, A., Pey, J., Cusack, M., Pérez, N., Mihalopoulos, N., Theodosi, C., Gerasopoulos, E., Kubilay, N., and Koçak, M.: Variability in regional background aerosols within the Mediterranean. Atmos. Chem. Phys., 9, 4575–4591, http://dx.doi.org/10.5194/acp-9-4575-2009doi:10.5194/acp-9-4575-2009, 2009. </mixed-citation>
</ref>
<ref id="ref30">
<label>30</label><mixed-citation publication-type="other" xlink:type="simple"> Rodríguez, S., Querol, X., Alastuey, A., and Mantilla, E.: Origin of high PM10 and TSP concentrations in summer in Eastern Spain, Atmos. Environ., 36, 3101–3112, 2002. </mixed-citation>
</ref>
<ref id="ref31">
<label>31</label><mixed-citation publication-type="other" xlink:type="simple"> Rodríguez, S., Querol, X., Alastuey, A., Viana, M., and Mantilla E.: Events affecting levels and seasonal evolution of airborne particulate matter concentrations in the Western Mediterranean, Environ. Sci. Technol., 37, 216–222, 2003. </mixed-citation>
</ref>
<ref id="ref32">
<label>32</label><mixed-citation publication-type="other" xlink:type="simple"> Salmi, T., Määttä, A., Anttila, P., Ruoho-Airola, T., and Amnell, T.: Detecting trends of annual values of atmospheric pollutants by the Mann-Kendall test and Sen&apos;s slope estimates-the Excel template application MAKESENS, In publications on Air Quality No. 31 (ed. Finnish Meteorological Institute), Finnish Meteorological Institute, p 35, 2002. </mixed-citation>
</ref>
<ref id="ref33">
<label>33</label><mixed-citation publication-type="other" xlink:type="simple"> Seco, R., Peñuelas, J., Filella, I., Llusià, J., Molowny-Horas, R., Schallhart, S., Metzger, A., Müller, M., and Hansel, A.: Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions, Atmos. Chem. Phys., 11, 13161–13179, http://dx.doi.org/10.5194/acp-11-13161-2011doi:10.5194/acp-11-13161-2011, 2011. </mixed-citation>
</ref>
<ref id="ref34">
<label>34</label><mixed-citation publication-type="other" xlink:type="simple"> Soriano, C., Baldasano, J. M, Buttler, W. T., and Moore, K.: Circulatory Patterns of Air Pollutants within the Barcelona Air Basin in a summertime situation: Lidar and Numerical Approaches, Bound.-Lay. Meteorol., 98, 33–55, 2001. </mixed-citation>
</ref>
<ref id="ref35">
<label>35</label><mixed-citation publication-type="other" xlink:type="simple"> Tsyro, S., Yttri, K. E., and Aas, W.: Measurement and model assessment of particulate matter in Europe, 2009. EMEP Transboundary particulate matter in Europe Status Report, 4/2011, 23–52, 2011. </mixed-citation>
</ref>
<ref id="ref36">
<label>36</label><mixed-citation publication-type="other" xlink:type="simple"> Turpin, B. J. and Lim, H. J.: Species contributions to PM$_2.5$ mass concentrations: Revisiting common assumptions for estimating organic mass, Aerosol Sci. Technol., 35, 602–610, 2001. </mixed-citation>
</ref>
<ref id="ref37">
<label>37</label><mixed-citation publication-type="other" xlink:type="simple"> Vicente-Serrano, M. S., Trigo, M. R., López-Moreno, J. I., Liberato, M. L. R., Lorenzo-Lacruz, J., Beguería, S., Morán-Tejeda, E., and El Kenawy, A.: Extreme winter precipitation in the Iberian Peninsula 2010: anomalies, driving mechanisms and future projections. Clim. Res., 46, 51–65, 2011. </mixed-citation>
</ref>
<ref id="ref38">
<label>38</label><mixed-citation publication-type="other" xlink:type="simple"> Visbeck, M. H., Hurrell, J. W., Polvani, L., and Cullen, H. M.: The North Atlantic Oscillation: past, present and future, PNAS, 98, 12876–12877, 2001. </mixed-citation>
</ref>
</ref-list>
</back>
</article>