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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>
<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></publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acpd-13-23691-2013</article-id>
<title-group>
<article-title>The sensitivity of global climate to the episodicity of fire aerosol emissions</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Clark</surname>
<given-names>S. K.</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>Ward</surname>
<given-names>D. S.</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>Mahowald</surname>
<given-names>N. M.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY 14853, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>10</day>
<month>09</month>
<year>2013</year>
</pub-date>
<volume>13</volume>
<issue>9</issue>
<fpage>23691</fpage>
<lpage>23717</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2013 S. K. Clark et al.</copyright-statement>
<copyright-year>2013</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/3.0/">https://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://acp.copernicus.org/preprints/13/23691/2013/acpd-13-23691-2013.html">This article is available from https://acp.copernicus.org/preprints/13/23691/2013/acpd-13-23691-2013.html</self-uri>
<self-uri xlink:href="https://acp.copernicus.org/preprints/13/23691/2013/acpd-13-23691-2013.pdf">The full text article is available as a PDF file from https://acp.copernicus.org/preprints/13/23691/2013/acpd-13-23691-2013.pdf</self-uri>
<abstract>
<p>One of the major ways in which forest and grass fires have an impact on
global climate is through the release of aerosols. Most studies focusing on
calculating the radiative forcing and other climate impacts of fire aerosols
use monthly mean emissions derived from the Global Fire Emissions Database
that captures only the seasonal cycle of fire aerosol emissions. Here we
present the results of a sensitivity study that investigates the climate
response to the episodicity of the fires, based on the standard approach
which releases emissions every day, and contrasts that to the response when
fires are represented as intense pulses of emissions that occur only over
1–2 days on a monthly, yearly, or five-yearly basis. Overall we find that in
the modified cases with increased levels of episodicity, the all sky direct
effect radiative forcing increases, the clear sky direct effect radiative
forcing remains relatively constant, and the magnitude of the indirect effect
radiative forcing decreases by about 1 W m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; (from −1.6 to
−0.6 W m&lt;sup&gt;&amp;minus;2&lt;/sup&gt;). In the long term, we find that an increase in
aerosol emission episodicity leads to an asymmetric change in indirect
radiative forcing in the Northern Hemisphere compared to the Southern
Hemisphere contributes to a slight shift in the annual average position of
the intertropical convergence zone (ITCZ). This shift is found to have a
mixed effect on the overall performance of the model at predicting
precipitation rates in the tropics. Given these results we conclude that
future studies that look to assess the present day global climate impacts of
fire aerosols should consider the need to accurately represent fire
episodicity.</p>
</abstract>
<counts><page-count count="27"/></counts>
</article-meta>
</front>
<body/>
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