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<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">acpdD</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Atmos. Chem. Phys. Discuss.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7375</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acp-2017-296</article-id>
<title-group>
<article-title>Variability and quasi-decadal changes in the methane budget over
the period 2000&amp;ndash;2012</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Saunois</surname>
<given-names>Marielle</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>Bousquet</surname>
<given-names>Philippe</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>Poulter</surname>
<given-names>Benjamin</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>Peregon</surname>
<given-names>Anna</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>Ciais</surname>
<given-names>Philippe</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>Canadell</surname>
<given-names>Josep G.</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>Dlugokencky</surname>
<given-names>Edward J.</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>Etiope</surname>
<given-names>Giuseppe</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Bastviken</surname>
<given-names>David</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>Houweling</surname>
<given-names>Sander</given-names>
</name>
<xref ref-type="aff" rid="aff8">
<sup>8</sup>
</xref>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Janssens-Maenhout</surname>
<given-names>Greet</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>Tubiello</surname>
<given-names>Francesco N.</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>Castaldi</surname>
<given-names>Simona</given-names>
</name>
<xref ref-type="aff" rid="aff12">
<sup>12</sup>
</xref>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
<xref ref-type="aff" rid="aff14">
<sup>14</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Jackson</surname>
<given-names>Robert B.</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>Alexe</surname>
<given-names>Mihai</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>Arora</surname>
<given-names>Vivek K.</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>Beerling</surname>
<given-names>David J.</given-names>
</name>
<xref ref-type="aff" rid="aff17">
<sup>17</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Bergamaschi</surname>
<given-names>Peter</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>Blake</surname>
<given-names>Donald R.</given-names>
</name>
<xref ref-type="aff" rid="aff18">
<sup>18</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Brailsford</surname>
<given-names>Gordon</given-names>
</name>
<xref ref-type="aff" rid="aff19">
<sup>19</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Bruhwiler</surname>
<given-names>Lori</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>Crevoisier</surname>
<given-names>Cyril</given-names>
</name>
<xref ref-type="aff" rid="aff20">
<sup>20</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Crill</surname>
<given-names>Patrick</given-names>
</name>
<xref ref-type="aff" rid="aff21">
<sup>21</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Covey</surname>
<given-names>Kristofer</given-names>
</name>
<xref ref-type="aff" rid="aff22">
<sup>22</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Frankenberg</surname>
<given-names>Christian</given-names>
</name>
<xref ref-type="aff" rid="aff23">
<sup>23</sup>
</xref>
<xref ref-type="aff" rid="aff24">
<sup>24</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Gedney</surname>
<given-names>Nicola</given-names>
</name>
<xref ref-type="aff" rid="aff25">
<sup>25</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Höglund-Isaksson</surname>
<given-names>Lena</given-names>
</name>
<xref ref-type="aff" rid="aff26">
<sup>26</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ishizawa</surname>
<given-names>Misa</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ito</surname>
<given-names>Akihiko</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Joos</surname>
<given-names>Fortunat</given-names>
</name>
<xref ref-type="aff" rid="aff28">
<sup>28</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kim</surname>
<given-names>Heon-Sook</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kleinen</surname>
<given-names>Thomas</given-names>
</name>
<xref ref-type="aff" rid="aff29">
<sup>29</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Krummel</surname>
<given-names>Paul</given-names>
</name>
<xref ref-type="aff" rid="aff30">
<sup>30</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lamarque</surname>
<given-names>Jean-François</given-names>
</name>
<xref ref-type="aff" rid="aff31">
<sup>31</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Langenfelds</surname>
<given-names>Ray</given-names>
</name>
<xref ref-type="aff" rid="aff30">
<sup>30</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Locatelli</surname>
<given-names>Robin</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>Machida</surname>
<given-names>Toshinobu</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Maksyutov</surname>
<given-names>Shamil</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Melton</surname>
<given-names>Joe R.</given-names>
</name>
<xref ref-type="aff" rid="aff32">
<sup>32</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Morino</surname>
<given-names>Isamu</given-names>
</name>
<xref ref-type="aff" rid="aff33">
<sup>33</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Naik</surname>
<given-names>Vaishali</given-names>
</name>
<xref ref-type="aff" rid="aff34">
<sup>34</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>O'Doherty</surname>
<given-names>Simon</given-names>
</name>
<xref ref-type="aff" rid="aff35">
<sup>35</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Parmentier</surname>
<given-names>Frans-Jan W.</given-names>
</name>
<xref ref-type="aff" rid="aff36">
<sup>36</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Patra</surname>
<given-names>Prabir K.</given-names>
</name>
<xref ref-type="aff" rid="aff37">
<sup>37</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Peng</surname>
<given-names>Changhui</given-names>
</name>
<xref ref-type="aff" rid="aff38">
<sup>38</sup>
</xref>
<xref ref-type="aff" rid="aff39">
<sup>39</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Peng</surname>
<given-names>Shushi</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff40">
<sup>40</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Peters</surname>
<given-names>Glen P.</given-names>
</name>
<xref ref-type="aff" rid="aff41">
<sup>41</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Pison</surname>
<given-names>Isabelle</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>Prinn</surname>
<given-names>Ronald</given-names>
</name>
<xref ref-type="aff" rid="aff42">
<sup>42</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ramonet</surname>
<given-names>Michel</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>Riley</surname>
<given-names>William J.</given-names>
</name>
<xref ref-type="aff" rid="aff43">
<sup>43</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Saito</surname>
<given-names>Makoto</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Santini</surname>
<given-names>Monia</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>Schroeder</surname>
<given-names>Ronny</given-names>
</name>
<xref ref-type="aff" rid="aff44">
<sup>44</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Simpson</surname>
<given-names>Isobel J.</given-names>
</name>
<xref ref-type="aff" rid="aff18">
<sup>18</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Spahni</surname>
<given-names>Renato</given-names>
</name>
<xref ref-type="aff" rid="aff28">
<sup>28</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Takizawa</surname>
<given-names>Atsushi</given-names>
</name>
<xref ref-type="aff" rid="aff45">
<sup>45</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Thornton</surname>
<given-names>Brett F.</given-names>
</name>
<xref ref-type="aff" rid="aff22">
<sup>22</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Tian</surname>
<given-names>Hanqin</given-names>
</name>
<xref ref-type="aff" rid="aff46">
<sup>46</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Tohjima</surname>
<given-names>Yasunori</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Viovy</surname>
<given-names>Nicolas</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>Voulgarakis</surname>
<given-names>Apostolos</given-names>
</name>
<xref ref-type="aff" rid="aff47">
<sup>47</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Weiss</surname>
<given-names>Ray</given-names>
</name>
<xref ref-type="aff" rid="aff48">
<sup>48</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Wilton</surname>
<given-names>David J.</given-names>
</name>
<xref ref-type="aff" rid="aff17">
<sup>17</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Wiltshire</surname>
<given-names>Andy</given-names>
</name>
<xref ref-type="aff" rid="aff49">
<sup>49</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Worthy</surname>
<given-names>Doug</given-names>
</name>
<xref ref-type="aff" rid="aff50">
<sup>50</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Wunch</surname>
<given-names>Debra</given-names>
</name>
<xref ref-type="aff" rid="aff51">
<sup>51</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Xu</surname>
<given-names>Xiyan</given-names>
</name>
<xref ref-type="aff" rid="aff43">
<sup>43</sup>
</xref>
<xref ref-type="aff" rid="aff52">
<sup>52</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Yoshida</surname>
<given-names>Yukio</given-names>
</name>
<xref ref-type="aff" rid="aff27">
<sup>27</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Zhang</surname>
<given-names>Bowen</given-names>
</name>
<xref ref-type="aff" rid="aff46">
<sup>46</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Zhang</surname>
<given-names>Zhen</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<xref ref-type="aff" rid="aff53">
<sup>53</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Zhu</surname>
<given-names>Qiuan</given-names>
</name>
<xref ref-type="aff" rid="aff39">
<sup>39</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Laboratoire des Sciences du Climat et de l’Environnement, LSCE-IPSL (CEA-CNRS-UVSQ), Université Paris-Saclay 91191 Gif-sur-Yvette, France</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>NASA Goddard Space Flight Center, Biospheric Science Laboratory, Greenbelt, MD 20771, USA</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Global Carbon Project, CSIRO Oceans and Atmosphere, Canberra, ACT 2601, Australia</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>NOAA ESRL, 325 Broadway, Boulder, Colorado 80305, USA</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 2, via V. Murata 605 00143, Roma</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Faculty of Environmental Science and Engineering, Babes Bolyai University, Cluj-Napoca, Romania</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>Department of Thematic Studies – Environmental Change, Linköping University, SE-581 83 Linköping, Sweden</addr-line>
</aff>
<aff id="aff8">
<label>8</label>
<addr-line>Netherlands Institute for Space Research (SRON), Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands</addr-line>
</aff>
<aff id="aff9">
<label>9</label>
<addr-line>Institute for Marine and Atmospheric Research Sorbonnelaan 2, 3584 CA, Utrecht, The Netherlands</addr-line>
</aff>
<aff id="aff10">
<label>10</label>
<addr-line>European Commission Joint Research Centre, Ispra (Va), Italy</addr-line>
</aff>
<aff id="aff11">
<label>11</label>
<addr-line>Statistics Division, Food and Agriculture Organization of the United Nations (FAO), Viale delle Terme di Caracalla, Rome 00153, Italy</addr-line>
</aff>
<aff id="aff12">
<label>12</label>
<addr-line>Dipartimento di Scienze Ambientali, Biologiche e Farmaceutiche, Seconda Universita di Napoli, via Vivaldi 43, 81100 Caserta, Italy</addr-line>
</aff>
<aff id="aff13">
<label>13</label>
<addr-line>Far East Federal University (FEFU), Vladivostok, Russky Island, Russia</addr-line>
</aff>
<aff id="aff14">
<label>14</label>
<addr-line>Euro-Mediterranean Center on Climate Change, Via Augusto Imperatore 16, 73100 Lecce, Italy</addr-line>
</aff>
<aff id="aff15">
<label>15</label>
<addr-line>School of Earth, Energy &amp; Environmental Sciences, Stanford University, Stanford, CA 94305-2210, USA</addr-line>
</aff>
<aff id="aff16">
<label>16</label>
<addr-line>Canadian Centre for Climate Modelling and Analysis, Climate Research Division, Environment and Climate Change Canada, Victoria, BC, V8W 2Y2, Canada</addr-line>
</aff>
<aff id="aff17">
<label>17</label>
<addr-line>Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK</addr-line>
</aff>
<aff id="aff18">
<label>18</label>
<addr-line>University of California Irvine, 570 Rowland Hall, Irvine, California 92697, USA</addr-line>
</aff>
<aff id="aff19">
<label>19</label>
<addr-line>National Institute of Water and Atmospheric Research, 301 Evans Bay Parade, Wellington, New Zealand</addr-line>
</aff>
<aff id="aff20">
<label>20</label>
<addr-line>Laboratoire de Météorologie Dynamique, LMD/IPSL, CNRS Ecole polytechnique, Université Paris-Saclay, 91120 Palaiseau, France</addr-line>
</aff>
<aff id="aff21">
<label>21</label>
<addr-line>Department of Geological Sciences and Bolin Centre for Climate Research, Svante Arrhenius väg 8, SE-106 91 Stockholm, Sweden</addr-line>
</aff>
<aff id="aff22">
<label>22</label>
<addr-line>School of Forestry and Environmental Studies, Yale University New Haven, CT 06511, USA</addr-line>
</aff>
<aff id="aff23">
<label>23</label>
<addr-line>California Institute of Technology, Geological and Planetary Sciences, Pasadena, USA</addr-line>
</aff>
<aff id="aff24">
<label>24</label>
<addr-line>Jet Propulsion Laboratory, M/S 183-601, 4800 Oak Grove Drive, Pasadena, CA 91109, USA</addr-line>
</aff>
<aff id="aff25">
<label>25</label>
<addr-line>Met Office Hadley Centre, Joint Centre for Hydrometeorological Research, Maclean Building, Wallingford OX10 8BB, UK</addr-line>
</aff>
<aff id="aff26">
<label>26</label>
<addr-line>Air Quality and Greenhouse Gases program (AIR), International Institute for Applied Systems Analysis (IIASA), A-2361 Laxenburg, Austria</addr-line>
</aff>
<aff id="aff27">
<label>27</label>
<addr-line>Center for Global Environmental Research, National Institute for Environmental Studies (NIES), Onogawa 16-2, Tsukuba, Ibaraki 305-8506, Japan</addr-line>
</aff>
<aff id="aff28">
<label>28</label>
<addr-line>Climate and Environmental Physics, Physics Institute and Oeschger Center for Climate Change Research, University of Bern, Sidlerstr. 5, CH-3012 Bern, Switzerland</addr-line>
</aff>
<aff id="aff29">
<label>29</label>
<addr-line>Max Planck Institute for Meteorology, Bundesstrasse 53, 20146 Hamburg, Germany</addr-line>
</aff>
<aff id="aff30">
<label>30</label>
<addr-line>CSIRO Oceans and Atmosphere, Aspendale, Victoria 3195 Australia</addr-line>
</aff>
<aff id="aff31">
<label>31</label>
<addr-line>NCAR, PO Box 3000, Boulder, Colorado 80307-3000, USA</addr-line>
</aff>
<aff id="aff32">
<label>32</label>
<addr-line>Climate Research Division, Environment and Climate Change Canada, Victoria, BC, V8W 2Y2, Canada</addr-line>
</aff>
<aff id="aff33">
<label>33</label>
<addr-line>Center for Global Environmental Research, National Institute for Environmental Studies (NIES), Onogawa 16-2, Tsukuba, Ibaraki 305-8506, Japan</addr-line>
</aff>
<aff id="aff34">
<label>34</label>
<addr-line>NOAA, GFDL, 201 Forrestal Rd., Princeton, NJ 08540</addr-line>
</aff>
<aff id="aff35">
<label>35</label>
<addr-line>School of Chemistry, University of Bristol, Cantock&apos;s Close, Clifton, Bristol BS8 1TS</addr-line>
</aff>
<aff id="aff36">
<label>36</label>
<addr-line>Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT: The Arctic University of Norway, NO-9037, Tromsø, Norway</addr-line>
</aff>
<aff id="aff37">
<label>37</label>
<addr-line>Department of Environmental Geochemical Cycle Research and Institute of Arctic Climate and Environment Research, JAMSTEC, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, 236-0001, Japan</addr-line>
</aff>
<aff id="aff38">
<label>38</label>
<addr-line>Department of Biology Sciences, Institute of Environment Science, University of Quebec at Montreal, Montreal, QC H3C 3P8, Canada</addr-line>
</aff>
<aff id="aff39">
<label>39</label>
<addr-line>State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&amp;F University, Yangling, Shaanxi 712100, China</addr-line>
</aff>
<aff id="aff40">
<label>40</label>
<addr-line>Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China</addr-line>
</aff>
<aff id="aff41">
<label>41</label>
<addr-line>CICERO Center for International Climate Research, Pb. 1129 Blindern, 0318 Oslo, Norway</addr-line>
</aff>
<aff id="aff42">
<label>42</label>
<addr-line>Massachusetts Institute of Technology (MIT), Building 54-1312, Cambridge, MA 02139, USA</addr-line>
</aff>
<aff id="aff43">
<label>43</label>
<addr-line>Earth Sciences Division, Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA 94720, USA</addr-line>
</aff>
<aff id="aff44">
<label>44</label>
<addr-line>Department of Civil &amp; Environmental Engineering, University of New Hampshire, Durham, NH 03824, USA</addr-line>
</aff>
<aff id="aff45">
<label>45</label>
<addr-line>Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan</addr-line>
</aff>
<aff id="aff46">
<label>46</label>
<addr-line>International Center for Climate and Global Change Research, School of Forestry and Wildlife Sciences, Auburn University, 602 Duncan Drive, Auburn, AL 36849, USA</addr-line>
</aff>
<aff id="aff47">
<label>47</label>
<addr-line>Space &amp; Atmospheric Physics, The Blackett Laboratory, Imperial College London, London SW7 2AZ, UK</addr-line>
</aff>
<aff id="aff48">
<label>48</label>
<addr-line>Scripps Institution of Oceanography (SIO), University of California San Diego, La Jolla, CA 92093, USA</addr-line>
</aff>
<aff id="aff49">
<label>49</label>
<addr-line>Met Office Hadley Centre, FitzRoy Road, Exeter, EX1 3PB, United Kingdom</addr-line>
</aff>
<aff id="aff50">
<label>50</label>
<addr-line>Environnement Canada, 4905, rue Dufferin, Toronto, Canada</addr-line>
</aff>
<aff id="aff51">
<label>51</label>
<addr-line>Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario, Canada</addr-line>
</aff>
<aff id="aff52">
<label>52</label>
<addr-line>CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China</addr-line>
</aff>
<aff id="aff53">
<label>53</label>
<addr-line>Swiss Federal Research Institute WSL, Birmensdorf 8059, Switzerland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>18</day>
<month>04</month>
<year>2017</year>
</pub-date>
<volume>2017</volume>
<fpage>1</fpage>
<lpage>39</lpage>
<permissions>
<license license-type="open-access">
<license-p>This work is licensed under a Creative Commons Attribution 3.0 Unported License. To view a copy of this license, visit <ext-link ext-link-type="uri"  xlink:href="http://creativecommons.org/licenses/by/3.0/">http://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/acp-2017-296.html">This article is available from http://www.atmos-chem-phys-discuss.net/acp-2017-296.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/acp-2017-296.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/acp-2017-296.pdf</self-uri>
<abstract>
<p>Following the recent Global Carbon project (GCP) synthesis of the decadal methane (CH&lt;sub&gt;4&lt;/sub&gt;) budget over 2000&amp;ndash;2012 (Saunois et al., 2016), we analyse here the same dataset with a focus on quasi-decadal and inter-annual variability in CH&lt;sub&gt;4&lt;/sub&gt; emissions. The GCP dataset integrates results from top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling frameworks) and bottom-up models, inventories, and data-driven approaches (including process-based models for estimating land surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven extrapolations).
&lt;br&gt;&lt;br&gt;
The annual global methane emissions from top-down studies, which by construction match the observed methane growth rate within their uncertainties, all show an increase in total methane emissions over the period 2000&amp;ndash;2012, but this increase is not linear over the 13 years. Despite differences between individual studies, the mean emission anomaly of the top-down ensemble shows no significant trend in total methane emissions over the period 2000&amp;ndash;2006, during the plateau of atmospheric methane mole fractions, and also over the period 2008&amp;ndash;2012, during the renewed atmospheric methane increase. However, the top-down ensemble mean produces an emission shift between 2006 and 2008, leading to 22 [16&amp;ndash;32] Tg CH&lt;sub&gt;4&lt;/sub&gt; yr&lt;sup&gt;&amp;minus;1&lt;/sup&gt; higher methane emissions over the period 2008&amp;ndash;2012 compared to 2002&amp;ndash;2006. This emission increase mostly originated from the tropics with a smaller contribution from mid-latitudes and no significant change from boreal regions. 
&lt;br&gt;&lt;br&gt;
The regional contributions remain uncertain in top-down studies. Tropical South America and South and East Asia seems to contribute the most to the emission increase in the tropics. However, these two regions have only limited atmospheric measurements and remain therefore poorly constrained.
&lt;br&gt;&lt;br&gt;
The sectorial partitioning of this emission increase between the periods 2002&amp;ndash;2006 and 2008&amp;ndash;2012 differs from one atmospheric inversion study to another. However, all top-down studies suggest smaller changes in fossil fuel emissions (from oil, gas, and coal industries) compared to the mean of the bottom-up inventories included in this study. This difference is partly driven by a smaller emission change in China from the top-down studies compared to the estimate in the EDGARv4.2 inventory, which should be revised to smaller values in a near future. Though the sectorial partitioning of six individual top-down studies out of eight are not consistent with the observed change in atmospheric &lt;sup&gt;13&lt;/sup&gt;CH&lt;sub&gt;4&lt;/sub&gt;, the partitioning derived from the ensemble mean is consistent with this isotopic constraint. At the global scale, the top-down ensemble mean suggests that, the dominant contribution to the resumed atmospheric CH&lt;sub&gt;4&lt;/sub&gt; growth after 2006 comes from microbial sources (more from agriculture and waste sectors than from natural wetlands), with an uncertain but smaller contribution from fossil CH&lt;sub&gt;4&lt;/sub&gt; emissions. Besides, a decrease in biomass burning emissions (in agreement with the biomass burning emission databases) makes the balance of sources consistent with atmospheric &lt;sup&gt;13&lt;/sup&gt;CH&lt;sub&gt;4&lt;/sub&gt; observations.
&lt;br&gt;&lt;br&gt;
The methane loss (in particular through OH oxidation) has not been investigated in detail in this study, although it may play a significant role in the recent atmospheric methane changes.</p>
</abstract>
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