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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACP</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACP</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7324</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/acp-11-3375-2011</article-id>
<title-group>
<article-title>A new estimation of the recent tropospheric molecular hydrogen budget using atmospheric observations and variational inversion</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Yver</surname>
<given-names>C. E.</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>Pison</surname>
<given-names>I. C.</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>Fortems-Cheiney</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>Schmidt</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>Chevallier</surname>
<given-names>F.</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>Ramonet</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>Jordan</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Søvde</surname>
<given-names>O. A.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Engel</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Fisher</surname>
<given-names>R. E.</given-names>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lowry</surname>
<given-names>D.</given-names>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Nisbet</surname>
<given-names>E. G.</given-names>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Levin</surname>
<given-names>I.</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Hammer</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Necki</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff8">
<sup>8</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Bartyzel</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff8">
<sup>8</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Reimann</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Vollmer</surname>
<given-names>M. K.</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Steinbacher</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Aalto</surname>
<given-names>T.</given-names>
</name>
<xref ref-type="aff" rid="aff10">
<sup>10</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Maione</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Arduini</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>O&apos;Doherty</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff12">
<sup>12</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Grant</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff12">
<sup>12</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Sturges</surname>
<given-names>W. T.</given-names>
</name>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Forster</surname>
<given-names>G. L.</given-names>
</name>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lunder</surname>
<given-names>C. R.</given-names>
</name>
<xref ref-type="aff" rid="aff14">
<sup>14</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Privalov</surname>
<given-names>V.</given-names>
</name>
<xref ref-type="aff" rid="aff15">
<sup>15</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Paramonova</surname>
<given-names>N.</given-names>
</name>
<xref ref-type="aff" rid="aff15">
<sup>15</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Werner</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff16">
<sup>16</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Bousquet</surname>
<given-names>P.</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-group><aff id="aff1">
<label>1</label>
<addr-line>Laboratoire des Sciences du Climat et de l&apos;Environnement (LSCE), Gif-sur-Yvette, France</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Université de Versailles Saint-Quentin-en-Yvelines (UVSQ),  Versailles, France</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Max-Planck Institut für Biogeochemie, Jena, Germany</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>University of Oslo, Oslo, Norway</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Institut für Meteorologie und Geophysik, Goethe-Universität Frankfurt, Frankfurt, Germany</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Department of Earth Sciences, Royal Holloway, University of London, Egham, UK</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>Institut für Umweltphysik, Heidelberg Universität, Heidelberg, Germany</addr-line>
</aff>
<aff id="aff8">
<label>8</label>
<addr-line>Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Krakow, Poland</addr-line>
</aff>
<aff id="aff9">
<label>9</label>
<addr-line>Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Air Pollution/Environmental Technology, Duebendorf, Switzerland</addr-line>
</aff>
<aff id="aff10">
<label>10</label>
<addr-line>Finnish Meteorological Institute, Climate Change Research, Helsinki, Finland</addr-line>
</aff>
<aff id="aff11">
<label>11</label>
<addr-line>Universitá degli Studi di Urbino, DiSBeF, Sezione di Scienze Chimiche, Urbino, Italy</addr-line>
</aff>
<aff id="aff12">
<label>12</label>
<addr-line>School of Chemistry, University of Bristol, UK</addr-line>
</aff>
<aff id="aff13">
<label>13</label>
<addr-line>School of Environmental Sciences, University of East Anglia, Norwich, UK</addr-line>
</aff>
<aff id="aff14">
<label>14</label>
<addr-line>Norsk Institutt for Luftforskning, Kjeller, Norway</addr-line>
</aff>
<aff id="aff15">
<label>15</label>
<addr-line>Voeikov Main Geophysical Observatory, St. Petersburg, Russia</addr-line>
</aff>
<aff id="aff16">
<label>16</label>
<addr-line>Deutscher Wetterdienst, Meteorologisches Observatorium, Hohenpeissenberg, Germany</addr-line>
</aff>
<pub-date pub-type="epub">
<day>11</day>
<month>04</month>
<year>2011</year>
</pub-date>
<volume>11</volume>
<issue>7</issue>
<fpage>3375</fpage>
<lpage>3392</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.net/11/3375/2011/acp-11-3375-2011.html">This article is available from http://www.atmos-chem-phys.net/11/3375/2011/acp-11-3375-2011.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/11/3375/2011/acp-11-3375-2011.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/3375/2011/acp-11-3375-2011.pdf</self-uri>
<abstract>
<p>This paper presents an analysis of the recent tropospheric molecular hydrogen
(H&lt;sub&gt;2&lt;/sub&gt;) budget with a particular focus on soil uptake and European surface
emissions. A variational inversion scheme is combined with observations from
the RAMCES and EUROHYDROS atmospheric networks, which include continuous
measurements performed between mid-2006 and mid-2009. Net H&lt;sub&gt;2&lt;/sub&gt; surface flux, 
then deposition velocity and surface emissions and finally, deposition 
velocity, biomass burning, anthropogenic and N&lt;sub&gt;2&lt;/sub&gt;
fixation-related emissions were simultaneously inverted in several scenarios.
These scenarios have focused on the sensibility of the soil uptake value to
different spatio-temporal distributions. The range of variations of these
diverse inversion sets generate an estimate of the uncertainty for each term
of the H&lt;sub&gt;2&lt;/sub&gt; budget. The net H&lt;sub&gt;2&lt;/sub&gt; flux per region (High Northern Hemisphere,
Tropics and High Southern Hemisphere) varies between −8 and
+8 Tg yr&lt;sup&gt;−1&lt;/sup&gt;. The best inversion in terms of fit to the observations
combines updated prior surface emissions and a soil deposition velocity map
that is based on bottom-up and top-down estimations. Our estimate of global
H&lt;sub&gt;2&lt;/sub&gt; soil uptake is −59&amp;plusmn;9 Tg yr&lt;sup&gt;−1&lt;/sup&gt;. Forty per cent of this
uptake is located in the High Northern Hemisphere and 55% is located in the
Tropics. In terms of surface emissions, seasonality is mainly driven by
biomass burning emissions. The inferred European anthropogenic emissions are
consistent with independent H&lt;sub&gt;2&lt;/sub&gt; emissions estimated using a H&lt;sub&gt;2&lt;/sub&gt;/CO mass
ratio of 0.034 and CO emissions within the range of their respective
uncertainties. Additional constraints, such as isotopic measurements would be
needed to infer a more robust partition of H&lt;sub&gt;2&lt;/sub&gt; sources and sinks.</p>
</abstract>
<counts><page-count count="18"/></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"> Aalto, T., Lallo, M., Hatakka, J., and Laurila, T.: Atmospheric hydrogen variations and traffic emissions at an urban site in Finland, Atmos. Chem. Phys., 9, 7387–7396, http://dx.doi.org/10.5194/acp-9-7387-2009doi:10.5194/acp-9-7387-2009, 2009. </mixed-citation>
</ref>
<ref id="ref2">
<label>2</label><mixed-citation publication-type="other" xlink:type="simple"> Bonasoni, P., Calzolari, F., Colombo, T., Corazza, E., Santaguida, R., and Tesi, G.: Continuous CO and H&lt;sub&gt;2&lt;/sub&gt; measurements at Mt. Cimone (Italy): Preliminary results, Atmos. Environ., 31, 959–967, 1997. </mixed-citation>
</ref>
<ref id="ref3">
<label>3</label><mixed-citation publication-type="other" xlink:type="simple"> Bond, S., Vollmer, M., Steinbacher, M., Henne, S., and Reimann, S.: Atmospheric molecular hydrogen (H&lt;sub&gt;2&lt;/sub&gt;): Observations at the high-altitude site Jungfraujoch, Switzerland, Tellus, 61B, 64–76, doi:10.1111/j.1600-0889.2010.00509.x, 2010. </mixed-citation>
</ref>
<ref id="ref4">
<label>4</label><mixed-citation publication-type="other" xlink:type="simple"> Bousquet, P., Hauglustaine, D A., Peylin, P., Carouge, C., and Ciais, P.: Two decades of OH variability as inferred by an inversion of atmospheric transport and chemistry of methyl chloroform, Atmos. Chem. Phys., 5, 2635–2656, http://dx.doi.org/10.5194/acp-5-2635-2005doi:10.5194/acp-5-2635-2005, 2005. </mixed-citation>
</ref>
<ref id="ref5">
<label>5</label><mixed-citation publication-type="other" xlink:type="simple"> Bousquet, P., Yver, C., Pison, I., Li, Y S., Fortems, A., Hauglustaine, D., Szopa, S., Rayner, P J., Novelli, P., Langenfelds, R., Steele, P., Ramonet, M., Schmidt, M., Foster, P., Morfopoulos, C., and Ciais, P.: A three-dimensional synthesis inversion of the molecular hydrogen cycle: Sources and sinks budget and implications for the soil uptake, J. Geophys. Res., 116, doi:201110.1029/2010JD014599, 2011. </mixed-citation>
</ref>
<ref id="ref6">
<label>6</label><mixed-citation publication-type="other" xlink:type="simple"> Brasseur, G P., Hauglustaine, D A., Walters, S., Rasch, P J., Müller, J., Granier, C., and Tie, X X.: MOZART, a global chemical transport model for ozone and related chemical tracers 1. Model description, J. Geophys. Res., 103, 28265–28290, 1998. </mixed-citation>
</ref>
<ref id="ref7">
<label>7</label><mixed-citation publication-type="other" xlink:type="simple"> Chevallier, F., Fisher, M., Peylin, P., Serrar, S., Bousquet, P., Bréon, F., Chédin, A., and Ciais, P.: Inferring CO2 sources and sinks from satellite observations: Method and application to TOVS data, J. Geophys. Res., 110, D24309, doi:10.1029/2005JD006390, 2005. </mixed-citation>
</ref>
<ref id="ref8">
<label>8</label><mixed-citation publication-type="other" xlink:type="simple"> Chevallier, F., Bréon, F., and Rayner, P J.: Contribution of the Orbiting Carbon Observatory to the estimation of CO&lt;sub&gt;2&lt;/sub&gt; sources and sinks: Theoretical study in a variational data assimilation framework, J. Geophys. Res., 112, 11 pp., doi:200710.1029/2006JD007375, 2007. </mixed-citation>
</ref>
<ref id="ref9">
<label>9</label><mixed-citation publication-type="other" xlink:type="simple"> Conrad, R. and Seiler, W.: Decomposition of Atmospheric Hydrogen By Soil Microorganisms and Soil Enzymes., Soil Biol. Biochem., 13, 43–49, 1981. </mixed-citation>
</ref>
<ref id="ref10">
<label>10</label><mixed-citation publication-type="other" xlink:type="simple"> Conrad, R. and Seiler, W.: Influence of temperature, moisture, and organic carbon on the flux of H&lt;sub&gt;2&lt;/sub&gt; and CO between soil and atmosphere: Field studies in subtropical regions, J. Geophys. Res., 90, 5699–5709, 1985. </mixed-citation>
</ref>
<ref id="ref11">
<label>11</label><mixed-citation publication-type="other" xlink:type="simple"> Ehhalt, D H. and Rohrer, F.: The tropospheric cycle of H&lt;sub&gt;2&lt;/sub&gt;: A critical review, Tellus, 61B, 500–535, 2009. </mixed-citation>
</ref>
<ref id="ref12">
<label>12</label><mixed-citation publication-type="other" xlink:type="simple"> Engel, A. and EUROHYDROS PIs: EUROHYDROS, A European Network for Atmospheric Hydrogen observations and studies., in: EUROHYDROS Final Report, http://cordis.europa.eu/, 2009. </mixed-citation>
</ref>
<ref id="ref13">
<label>13</label><mixed-citation publication-type="other" xlink:type="simple"> Erickson, D J. and Taylor, J A.: 3-D tropospheric CO modeling - The possible influence of the ocean, Geophys. Res. Lett., 19, 1955–1958, 1992. </mixed-citation>
</ref>
<ref id="ref14">
<label>14</label><mixed-citation publication-type="other" xlink:type="simple"> Folberth, G., Hauglustaine, D A., Ciais, P., and Lathière, J.: On the role of atmospheric chemistry in the global CO 2 budget, Geophys. Res. Lett, 32, L0881, doi:10.1029/2004GL021812, 2005. </mixed-citation>
</ref>
<ref id="ref15">
<label>15</label><mixed-citation publication-type="other" xlink:type="simple"> Gerst, S. and Quay, P.: The deuterium content of atmospheric molecular hydrogen: Method and initial measurements, J. Geophys. Res., 105, 26433–26446, 2000. </mixed-citation>
</ref>
<ref id="ref16">
<label>16</label><mixed-citation publication-type="other" xlink:type="simple"> Gerst, S. and Quay, P.: Deuterium component of the global molecular hydrogen cycle, J. Geophys. Res., 106, 5021–5029, 2001. </mixed-citation>
</ref>
<ref id="ref17">
<label>17</label><mixed-citation publication-type="other" xlink:type="simple"> Granier, C., Hao, W M., Brasseur, G., and Müller, J.-F.: Land use practices and biomass burning: Impact on the chemical composition of the atmosphere, in Biomass Burning and Global Change, edited by: Levine, J. S., MIT Press, Cambridge, Mass., USA, 140–148, 1996. </mixed-citation>
</ref>
<ref id="ref18">
<label>18</label><mixed-citation publication-type="other" xlink:type="simple"> Grant, A., Witham, C., Simmonds, P., Manning, A., and O&apos;Doherty, S.: A 15 year record of high-frequency, in situ measurements of hydrogen at Mace Head, Ireland, Atmos. Chem. Phys., 10, 1203–1214, http://dx.doi.org/10.5194/acp-10-1203-2010doi:10.5194/acp-10-1203-2010, 2010. </mixed-citation>
</ref>
<ref id="ref19">
<label>19</label><mixed-citation publication-type="other" xlink:type="simple"> Group, G. S. D T.: Global Gridded Surfaces of Selected Soil Characteristics (IGBP-DIS). Data set, Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, USA, http://www.daac.ornl.gov, 2000. </mixed-citation>
</ref>
<ref id="ref20">
<label>20</label><mixed-citation publication-type="other" xlink:type="simple"> Hammer, S. and Levin, I.: Seasonal variation of the molecular hydrogen uptake by soils inferred from continuous atmospheric observations in Heidelberg, southwest Germany, Tellus, 61B, 556–565, 2009. </mixed-citation>
</ref>
<ref id="ref21">
<label>21</label><mixed-citation publication-type="other" xlink:type="simple"> Hammer, S., Vogel, F., Kaul, M., and Levin, I.: The H&lt;sub&gt;2&lt;/sub&gt;/CO ratio of emissions from combustion sources: comparison of top-down with bottom-up measurements in southwest Germany, Tellus, 61B, 547–555, 2009. </mixed-citation>
</ref>
<ref id="ref22">
<label>22</label><mixed-citation publication-type="other" xlink:type="simple"> Hao, W M., Ward, D E., Olbu, G., and Baker, S P.: Emissions of CO&lt;sub&gt;2&lt;/sub&gt;, CO, and hydrocarbons from fires in diverse African savanna ecosystems, J. Geophys. Res., 101, 23577–23584, 1996. </mixed-citation>
</ref>
<ref id="ref23">
<label>23</label><mixed-citation publication-type="other" xlink:type="simple"> Hauglustaine, D A. and Ehhalt, D H.: A three-dimensional model of molecular hydrogen in the troposphere, J. Geophys. Res., 107, 4330, doi:10.1029/2001JD001156, 2002. </mixed-citation>
</ref>
<ref id="ref24">
<label>24</label><mixed-citation publication-type="other" xlink:type="simple"> Hauglustaine, D A., Hourdin, F., Jourdain, L., Filiberti, M A., Walters, S., Lamarque, J F., and Holland, E A.: Interactive chemistry in the Laboratoire de Meteorologie Dynamique general circulation model: Description and background tropospheric chemistry evaluation, J. Geophys. Res., 109, D04314, doi:10.1029/2003JD003957, 2004. </mixed-citation>
</ref>
<ref id="ref25">
<label>25</label><mixed-citation publication-type="other" xlink:type="simple"> Hough, A M.: Development of a Two-Dimensional Global Tropospheric Model: Model Chemistry, J. Geophys. Res., 96, 7325–7362, 1991. </mixed-citation>
</ref>
<ref id="ref26">
<label>26</label><mixed-citation publication-type="other" xlink:type="simple"> Hourdin, F. and Talagrand, O.: Eulerian backtracking of atmospheric tracers. I: Adjoint derivation and parametrization of subgrid-scale transport, Quarterly J. Roy. Meteorol. Soc., 132, 567–583, 2006. </mixed-citation>
</ref>
<ref id="ref27">
<label>27</label><mixed-citation publication-type="other" xlink:type="simple"> Hourdin, F., Musat, I., Bony, S., Braconnot, P., Codron, F., Dufresne, J., Fairhead, L., Filiberti, M., Friedlingstein, P., Grandpeix, J., Krinner, G., LeVan, P., Li, Z., and Lott, F.: The LMDZ4 general circulation model: climate performance and sensitivity to parametrized physics with emphasis on tropical convection, Clim. Dynam., 27, 787–813, 2006. </mixed-citation>
</ref>
<ref id="ref28">
<label>28</label><mixed-citation publication-type="other" xlink:type="simple"> Jordan, A. and Steinberg, B.: Calibration of atmospheric hydrogen measurements, Atmos. Meas. Tech., 4, 509–521, http://dx.doi.org/10.5194/amt-4-509-2011doi:10.5194/amt-4-509-2011, 2011. </mixed-citation>
</ref>
<ref id="ref29">
<label>29</label><mixed-citation publication-type="other" xlink:type="simple"> Kaminski, T., Rayner, P J., Heimann, M., and Enting, I G.: On aggregation errors in atmospheric transport inversions, J. Geophys. Res., 106, 4703–4715, doi:200110.1029/2000JD900581, 2000. </mixed-citation>
</ref>
<ref id="ref30">
<label>30</label><mixed-citation publication-type="other" xlink:type="simple"> Khalil, M. A K. and Rasmussen, R A.: Global increase of atmospheric molecular hydrogen, Nature, 347, 743–745, 1990. </mixed-citation>
</ref>
<ref id="ref31">
<label>31</label><mixed-citation publication-type="other" xlink:type="simple"> Krol, M C., Lelieveld, J., Oram, D E., Sturrock, G A., Penkett, S A., Brenninkmeijer, C. A M., Gros, V., Williams, J., and Scheeren, H A.: Continuing emissions of methyl chloroform from Europe, Nature, 421, 131–135, 2003. </mixed-citation>
</ref>
<ref id="ref32">
<label>32</label><mixed-citation publication-type="other" xlink:type="simple"> Lallo, M., Aalto, T., Laurila, T., and Hatakka, J.: Seasonal variations in hydrogen deposition to boreal forest soil in southern Finland, Geophys. Res. Lett., 35, L04402, doi:10.1029/2007GL032357, 2008. </mixed-citation>
</ref>
<ref id="ref33">
<label>33</label><mixed-citation publication-type="other" xlink:type="simple"> Lallo, M., Aalto, T., Hatakka, J., and Laurila, T.: Hydrogen soil deposition at an urban site in Finland, Atmos. Chem. Phys., 9, 8559–8571, http://dx.doi.org/10.5194/acp-9-8559-2009doi:10.5194/acp-9-8559-2009, 2009. </mixed-citation>
</ref>
<ref id="ref34">
<label>34</label><mixed-citation publication-type="other" xlink:type="simple"> Lamarque, J.-F., Bond, T. C., Eyring, V., Granier, C., Heil, A., Klimont, Z., Lee, D., Liousse, C., Mieville, A., Owen, B., Schultz, M. G., Shindell, D., Smith, S. J., Stehfest, E., Van Aardenne, J., Cooper, O. R., Kainuma, M., Mahowald, N., McConnell, J. R., Naik, V., Riahi, K., and van Vuuren, D. P.: Historical (1850-2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application, Atmos. Chem. Phys., 10, 7017–7039, http://dx.doi.org/10.5194/acp-10-7017-2010doi:10.5194/acp-10-7017-2010, 2010. </mixed-citation>
</ref>
<ref id="ref35">
<label>35</label><mixed-citation publication-type="other" xlink:type="simple"> Langenfelds, R L., Francey, R J., Pak, B C., Steele, L P., Lloyd, J., Trudinger, C M., and Allison, C E.: Interannual growth rate variations of atmospheric CO 2 and its $\delta^13$C, H&lt;sub&gt;2&lt;/sub&gt;, CH&lt;sub&gt;4&lt;/sub&gt;, and CO between 1992 and 1999 linked to biomass burning, Global Biogeochem. Cy., 16, 1048, doi:10.1029/2001GB001466, 2002. </mixed-citation>
</ref>
<ref id="ref36">
<label>36</label><mixed-citation publication-type="other" xlink:type="simple"> Morfopoulos, C., Foster, P., Friedlingstein, P., Bousquet, P., and Prentice, I.: Modelling the soil consumption of atmospheric hydrogen at a global scale,  Global Biogeochem. Cy., submitted, 2010. </mixed-citation>
</ref>
<ref id="ref37">
<label>37</label><mixed-citation publication-type="other" xlink:type="simple"> Müller, J.: Geographical Distribution and Seasonal Variation of Surface Emissions and Deposition Velocities of Atmospheric Trace Gases, J. Geophys. Res., 97, 3787–3804, 1992. </mixed-citation>
</ref>
<ref id="ref38">
<label>38</label><mixed-citation publication-type="other" xlink:type="simple"> Novelli, P C., Lang, P M., Masarie, K A., Hurst, D F., Myers, R., and Elkins, J W.: Molecular hydrogen in the troposphere- Global distribution and budget, J. Geophys. Res., 104, 30427–30444, 1999. </mixed-citation>
</ref>
<ref id="ref39">
<label>39</label><mixed-citation publication-type="other" xlink:type="simple"> Olivier, J. G J., Bouwman, A F., van~der Maas, C. W M., Berdowski, J. J M., Veldt, C., Bloos, J. P J., Visschedijk, A. J H., Zandveld, P. Y J., and Haverlag, J L.: Description of EDGAR Version 2.0: A set of global emission inventories of greenhouse gases and ozone-depleting substances for all anthropogenic and most natural sources on a per country basis and on 1 degree × 1 degree grid, Rijksinstituut voor Volksgezondheid en Milieu RIVM, 1996. </mixed-citation>
</ref>
<ref id="ref40">
<label>40</label><mixed-citation publication-type="other" xlink:type="simple"> Pison, I., Bousquet, P., Chevallier, F., Szopa, S., and Hauglustaine, D.: Multi-species inversion of CH4, CO and H2 emissions from surface measurements, Atmos. Chem. Phys., 9, 5281–5297, http://dx.doi.org/10.5194/acp-9-5281-2009doi:10.5194/acp-9-5281-2009, 2009. </mixed-citation>
</ref>
<ref id="ref41">
<label>41</label><mixed-citation publication-type="other" xlink:type="simple"> Price, H., Jaegle, L., Rice, A., Quay, P., Novelli, P C., and Gammon, R.: Global budget of molecular hydrogen and its deuterium content: Constraints from ground station, cruise, and aircraft observations, J. Geophys. Res., 112, D22108, doi:10.1029/2006JD008152, 2007. </mixed-citation>
</ref>
<ref id="ref42">
<label>42</label><mixed-citation publication-type="other" xlink:type="simple"> Prinn, R G., Weiss, R F., Fraser, P J., Simmonds, P G., Cunnold, D M., Alyea, F N., O&apos;Doherty, S., Salameh, P., Miller, B R., Huang, J., Wang, R. H J., Hartley, D E., Harth, C., Steele, L P., Sturrock, G., Midgley, P M., and McCulloch, A.: A history of chemically and radiatively important gases in air deduced from ALE/GAGE/AGAGE, J. Geophys. Res., 105, 751–792, 2000. </mixed-citation>
</ref>
<ref id="ref43">
<label>43</label><mixed-citation publication-type="other" xlink:type="simple"> Prinn, R G., Huang, J., Weiss, R F., Cunnold, D M., Fraser, P J., Simmonds, P G., McCulloch, A., Harth, C., Reimann, S., and Salameh, P.: Evidence for variability of atmospheric hydroxyl radicals over the past quarter century, Geophys. Res. Lett., 32, L07809, doi:10.1029/2004GL022228, 2005. </mixed-citation>
</ref>
<ref id="ref44">
<label>44</label><mixed-citation publication-type="other" xlink:type="simple"> Rahn, T., Eiler, J M., Boering, K A., Wennberg, P O., McCarthy, M C., Tyler, S., Schauffler, S., Donnelly, S., and Atlas, E.: Extreme deuterium enrichment in stratospheric hydrogen and the global atmospheric budget of H&lt;sub&gt;2&lt;/sub&gt;, Nature, 424, 918–921, 2003. </mixed-citation>
</ref>
<ref id="ref45">
<label>45</label><mixed-citation publication-type="other" xlink:type="simple"> Rhee, T S., Brenninkmeijer, C. A M., and Röckmann, T.: The overwhelming role of soils in the global atmospheric hydrogen cycle, Atmos. Chem. Phys., 6, 1611–1625, http://dx.doi.org/10.5194/acp-6-1611-2006doi:10.5194/acp-6-1611-2006, 2006. </mixed-citation>
</ref>
<ref id="ref46">
<label>46</label><mixed-citation publication-type="other" xlink:type="simple"> Röckmann, T., Rhee, T S., and Engel, A.: Heavy hydrogen in the stratosphere, Atmos. Chem. Phys., 3, 2015–2023, http://dx.doi.org/10.5194/acp-3-2015-2003doi:10.5194/acp-3-2015-2003, 2003. </mixed-citation>
</ref>
<ref id="ref47">
<label>47</label><mixed-citation publication-type="other" xlink:type="simple"> Sanderson, M G., Collins, W J., Derwent, R G., and Johnson, C E.: Simulation of Global Hydrogen Levels Using a Lagrangian Three-Dimensional Model, J. Atmos. Chem., 46, 15–28, 2003. </mixed-citation>
</ref>
<ref id="ref48">
<label>48</label><mixed-citation publication-type="other" xlink:type="simple"> Schillert, A.: Parameters influencing the seasonality of H2 uptake in soils., State Examination Thesis, 2010. </mixed-citation>
</ref>
<ref id="ref49">
<label>49</label><mixed-citation publication-type="other" xlink:type="simple"> Schmidt, U.: The latitudinal and vertical distribution of molecular hydrogen in the troposphere, J. Geophys. Res., 83, 941–946, 1978. </mixed-citation>
</ref>
<ref id="ref50">
<label>50</label><mixed-citation publication-type="other" xlink:type="simple"> Schmitt, S., Hanselmann, A., Wollschläger, U., Hammer, S., and Levin, I.: Investigation of parameters controlling the soil sink of atmospheric molecular hydrogen, Tellus, 61B, 416–423, 2009. </mixed-citation>
</ref>
<ref id="ref51">
<label>51</label><mixed-citation publication-type="other" xlink:type="simple"> Sitch, S., Smith, B., Prentice, I C., Arneth, A., Bondeau, A., Cramer, W., Kaplan, J O., Levis, S., Lucht, W., Sykes, M T., Thonicke, K., and Venevsky, S.: Evaluation of ecosystem dynamics, plant geography and terrestrial carbon cycling in the LPJ dynamic global vegetation model, Global Change Biol., 9, 161–185, 2003. </mixed-citation>
</ref>
<ref id="ref52">
<label>52</label><mixed-citation publication-type="other" xlink:type="simple"> Søvde, O A., Gauss, M., Smyshlyaev, S P., and Isaksen, I. S A.: Evaluation of the chemical transport model Oslo CTM2 with focus on arctic winter ozone depletion, J. Geophys. Res., 113, D09304, doi:10.1029/2007JD009240, 2008. </mixed-citation>
</ref>
<ref id="ref53">
<label>53</label><mixed-citation publication-type="other" xlink:type="simple"> Thiruchittampalam, B. and Köble, R.: European emissions map, Institut für Energiewirtschaft und Rationelle Energieanwendung(IER); University of Stuttgart, http://carboeurope.ier.uni-stuttgart.de/, 2004. </mixed-citation>
</ref>
<ref id="ref54">
<label>54</label><mixed-citation publication-type="other" xlink:type="simple"> van~der Werf, G R., Randerson, J T., Giglio, L., Collatz, G J., Kasibhatla, P S., and Arellano, A F.: Interannual variability in global biomass burning emissions from 1997 to 2004, Atmos. Chem. Phys., 6, 3423–3441, http://dx.doi.org/10.5194/acp-6-3423-2006doi:10.5194/acp-6-3423-2006, 2006. </mixed-citation>
</ref>
<ref id="ref55">
<label>55</label><mixed-citation publication-type="other" xlink:type="simple"> Xiao, X., Prinn, R., Simmonds, P., Steele, L., Novelli, P., Huang, J., Langenfelds, R., O&apos;Doherty, S., Krummel, P., and Fraser, P.: Optimal estimation of the soil uptake rate of molecular hydrogen from the Advanced Global Atmospheric Gases Experiment and other measurements, J. Geophys. Res., 112, D07303, doi:10.1029/2006JD007241, 2007. </mixed-citation>
</ref>
<ref id="ref56">
<label>56</label><mixed-citation publication-type="other" xlink:type="simple"> Yonemura, S., Kawashima, S., and Tsuruta, H.: Continuous measurements of CO and H2 deposition velocities onto an andisol: uptake control by soil moisture, Tellus B – Chem. Phys. Meteorol. B, 51, 688–700, 1999. </mixed-citation>
</ref>
<ref id="ref57">
<label>57</label><mixed-citation publication-type="other" xlink:type="simple"> Yonemura, S., Kawashima, S., and Tsuruta, H.: Carbon monoxide, hydrogen, and methane uptake by soils in a temperate arable field and a forest, J. Geophys. Res., 105, 14347–14362, 2000a. </mixed-citation>
</ref>
<ref id="ref58">
<label>58</label><mixed-citation publication-type="other" xlink:type="simple"> Yonemura, S., Yokozawa, M., Kawashima, S., and Tsuruta, H.: Model Analysis of the Influence of Gas Diffusivity in Soil on Co and H2 Uptake, Tellus, 52B, 919–933, 2000b. </mixed-citation>
</ref>
<ref id="ref59">
<label>59</label><mixed-citation publication-type="other" xlink:type="simple"> Yver, C., Schmidt, M., Bousquet, P., Zahorowski, W., and Ramonet, M.: Estimation of the molecular hydrogen soil uptake and traffic emissions at a suburban site near Paris through hydrogen, carbon monoxide, and radon-222 semicontinuous measurements, J. Geophys. Res.-Atmos., 114, D18304, doi:10.1029/2009JD012122, 2009. </mixed-citation>
</ref>
</ref-list>
</back>
</article>