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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-12-2853-2012</article-id>
<title-group>
<article-title>Comment on &quot;Tropospheric temperature response to stratospheric  ozone recovery in the 21st century&quot; by Hu et al. (2011)</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Previdi</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>Polvani</surname>
<given-names>L. 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-group><aff id="aff1">
<label>1</label>
<addr-line>Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Applied Physics and Applied Mathematics and Department of Earth and Environmental Sciences, Columbia University, New York, NY, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>27</day>
<month>01</month>
<year>2012</year>
</pub-date>
<volume>12</volume>
<issue>1</issue>
<fpage>2853</fpage>
<lpage>2861</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>
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<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/12/2853/2012/acpd-12-2853-2012.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/12/2853/2012/acpd-12-2853-2012.pdf</self-uri>
<abstract>
<p>Stratospheric ozone recovery is expected to figure prominently in
      twenty-first century climate change. In a recent paper, Hu et al.
      (2011) argue that one impact of ozone recovery will be to enhance the
      warming of the surface-troposphere system produced by increases in
      well-mixed greenhouse gases; furthermore, this enhanced warming would
      be strongest in the Northern Hemisphere, which is surprising since
      previous studies have consistently shown the effects of stratospheric
      ozone changes to be most pronounced in the Southern Hemisphere. Hu
      et al. (2011) base their claims largely on differences in the
      simulated temperature change between two groups of IPCC climate
      models, one group which included stratospheric ozone recovery in its
      twenty-first century simulations and a second group which did
      not. Both groups of models were forced with the same increases in
      well-mixed greenhouse gases according to the A1B emissions
      scenario. In the current work, we compare the surface temperature
      responses of the same two groups of models in a different experiment
      in which atmospheric CO&lt;sub&gt;2&lt;/sub&gt; was increased by 1% per year until
      doubling. We find remarkably similar differences in the simulated
      surface temperature change between the two sets of models as Hu
      et al. (2011) found for the A1B experiment, suggesting that the
      enhanced warming which they attribute to stratospheric ozone recovery
      is actually a reflection of different responses of the two model
      groups to greenhouse gas forcing.</p>
</abstract>
<counts><page-count count="9"/></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"> Hu,~Y., Xia,~Y., and Fu,~Q.: Tropospheric temperature response to stratospheric ozone recovery in the 21st century, Atmos. Chem. Phys., 11, 7687–7699, http://dx.doi.org/10.5194/acp-11-7687-2011doi:10.5194/acp-11-7687-2011, 2011. </mixed-citation>
</ref>
<ref id="ref2">
<label>2</label><mixed-citation publication-type="other" xlink:type="simple"> McLandress, C., Perlwitz, J., and Shepherd, T. G.: Comment on &quot;Tropospheric temperature response to stratospheric ozone recovery in the 21st century&quot; by Hu et al. (2011), Atmos. Chem. Phys. Discuss., 11, 32993–33012, http://dx.doi.org/10.5194/acpd-11-32993-2011doi:10.5194/acpd-11-32993-2011, 2011a. </mixed-citation>
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<label>4</label><mixed-citation publication-type="other" xlink:type="simple"> Polvani,~L M., Previdi,~M., and Deser,~C.: Large cancellation, due to ozone recovery, of \mboxfuture Southern Hemisphere atmospheric circulation trends, Geophys. Res. Lett., 38, L04707, http://dx.doi.org/10.1029/2011GL046712doi:10.1029/2011GL046712, 2011a. </mixed-citation>
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<label>8</label><mixed-citation publication-type="other" xlink:type="simple"> Son,~S.-W., Gerber,~E P., Perlwitz,~J., Polvani,~L M., Gillett,~N., Seo,~K.-H., and SPARC/CCMVal co-authors: Impact of stratospheric ozone on Southern Hemisphere circulation change: a~multimodel assessment, J. Geophys. Res., 115, D00M07, http://dx.doi.org/10.1029/2010JD014271doi:10.1029/2010JD014271, 2010. </mixed-citation>
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</ref-list>
</back>
</article>