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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-14-18943-2014</article-id>
<title-group>
<article-title>Long-term observation of aerosol–cloud relationships in the Mid-Atlantic of the United States</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Li</surname>
<given-names>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>Joseph</surname>
<given-names>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>Min</surname>
<given-names>Q.</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>Yin</surname>
<given-names>B.</given-names>
<ext-link>https://orcid.org/0000-0003-2956-0899</ext-link>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Howard University, 2355 6th Street, NW, Washington DC, 20059, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Atmospheric Sciences Research Center, State University of New York at Albany, Albany, NY 12203, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>21</day>
<month>07</month>
<year>2014</year>
</pub-date>
<volume>14</volume>
<issue>13</issue>
<fpage>18943</fpage>
<lpage>18960</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2014 S. Li et al.</copyright-statement>
<copyright-year>2014</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/14/18943/2014/acpd-14-18943-2014.html">This article is available from https://acp.copernicus.org/preprints/14/18943/2014/acpd-14-18943-2014.html</self-uri>
<self-uri xlink:href="https://acp.copernicus.org/preprints/14/18943/2014/acpd-14-18943-2014.pdf">The full text article is available as a PDF file from https://acp.copernicus.org/preprints/14/18943/2014/acpd-14-18943-2014.pdf</self-uri>
<abstract>
<p>Long-term ground-based observations (2006 to 2010) of aerosol and cloud properties derived from
  passive radiometric sensors deployed at an atmospheric measurement field station in the
  Baltimore–Washington corridor operated by Howard University were used to examine aerosol indirect
  effect on cloud optical depth (COD), liquid water path (LWP), cloud droplets effective radius (&lt;i&gt;R&lt;/i&gt;&lt;sub&gt;e&lt;/sub&gt;)
  and cloud droplets number concentration (&lt;i&gt;N&lt;/i&gt;&lt;sub&gt;d&lt;/sub&gt;).  A higher frequency of clouds with
  large COD (&gt; 20) and small &lt;i&gt;R&lt;/i&gt;&lt;sub&gt;e&lt;/sub&gt; (&lt; 7 m) was found during summer of 2006 and 2007 along
  with higher frequency of abundant aerosol loading. The five-year data are screened for summer
  months only and are separated into clean and polluted cases based on aerosol particulate matter
  with aerodynamic diameter ≤ 2.5 m (PM&lt;sub&gt;2.5&lt;/sub&gt;) value. Evidence of aerosol indirect
   effect is found where for polluted cases the mean and median values of COD
   and &lt;i&gt;N&lt;/i&gt;&lt;sub&gt;d&lt;/sub&gt; distributions were elevated while the mean and median values of 
&lt;i&gt;R&lt;/i&gt;&lt;sub&gt;e&lt;/sub&gt; were decreased. Further reinforcing
  this conclusion is the result that the mean and median values of LWP distributions did not show
  prominent difference between clean and polluted cases, this implies that differences between
  the two cases of influential factors on cloud properties were relatively controlled. Moreover
  aerosol indirect effects were found insignificant when LWP was small but significant when LWP was
  large through the analysis of sensitivity of &lt;i&gt;N&lt;/i&gt;&lt;sub&gt;d&lt;/sub&gt; to LWP under different aerosol
  loading and the measurements of aerosol size distribution.</p>
</abstract>
<counts><page-count count="18"/></counts>
<funding-group>
<award-group id="gs1">
<funding-source></funding-source>
<award-id>NA11SEC4810003</award-id>
</award-group>
</funding-group>
</article-meta>
</front>
<body/>
<back>
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