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<article language="en">
	<journal>
		<journal_title>Atmospheric Chemistry and Physics Discussions</journal_title>
		<journal_url>www.atmos-chem-phys-discuss.net</journal_url>
		<issn>1680-7367</issn>
		<eissn>1680-7375</eissn>
		<volume_number>9</volume_number>
		<issue_number>1</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/acpd-9-1123-2009</doi>
	<article_url>http://www.atmos-chem-phys-discuss.net/9/1123/2009/</article_url>
	<abstract_html>http://www.atmos-chem-phys-discuss.net/9/1123/2009/acpd-9-1123-2009.html</abstract_html>
	<fulltext_pdf>http://www.atmos-chem-phys-discuss.net/9/1123/2009/acpd-9-1123-2009.pdf</fulltext_pdf>
	<start_page>1123</start_page>
	<end_page>1155</end_page>
	<publication_date>2009-01-14</publication_date>
	<article_title content_type="html">Lightning NO&lt;sub&gt;x&lt;/sub&gt; emissions over the USA investigated  using TES, NLDN, LRLDN, IONS data and the GEOS-Chem model</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>L. Jourdain</name>
			<email>ljourd@gmail.com</email>
		</author>
		<author numeration="2" affiliations="1">
			<name>S. S. Kulawik</name>
		</author>
		<author numeration="3" affiliations="2">
			<name>H. M. Worden</name>
		</author>
		<author numeration="4" affiliations="3">
			<name>K. E. Pickering</name>
		</author>
		<author numeration="5" affiliations="1">
			<name>J. Worden</name>
		</author>
		<author numeration="6" affiliations="4">
			<name>A. M. Thompson</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Jet Propulsion Laboratory, California Institute of Technology, 4800  Oak Grove Drive Pasadena, CA 91109, USA</affiliation>
		<affiliation numeration="2" content_type="html">National Center for Atmospheric Research, Boulder, CO, USA</affiliation>
		<affiliation numeration="3" content_type="html">NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA</affiliation>
		<affiliation numeration="4" content_type="html">Department of Meteorology, Pennsylvania State University, University  Park, PA 16802, USA</affiliation>
	</affiliations>
	<abstract content_type="html">Knowledge of the lightning source of NO&lt;sub&gt;x&lt;/sub&gt; is required to better
      understand NO&lt;sub&gt;x&lt;/sub&gt; and ozone distributions and changes in the
      troposphere, the oxidising capacity of the troposphere as well as some
      of the feedbacks between chemistry and climate change. In this paper,
      we use the National Lightning Detection (NLDN) and the Long Range
      Lightning Detection Network (LRLDN) data as well as the HYPSLIT
      transport and dispersion model to show the presence of ozone enhanced
      layers downwind of convective events in the ozone vertical profiles
      from the Tropospheric Emission Spectrometer (TES) instrument over the
      USA in July 2006. We use the TES dataset in conjunction with
      ozonesonde measurements from the Intercontinental Chemical Transport
      Experiment (INTEX) Ozonesonde Network Study (IONS) 2006 to test the
      parameterization of the lightning source of NO&lt;sub&gt;x&lt;/sub&gt; in a global
      chemistry transport model. We find that the global 3-D chemistry
      transport model GEOS-Chem with a lightning activity calculated with
      a parameterization based on cloud top height, scaled regionally and
      monthly to OTD/LIS (Optical Transient Detector/Lightning Imaging
      Sensor) climatology, and with a production of 260 mol NO/Flash
      captures the ozone enhancements seen by TES, but underestimates their
      intensities. We show that the model&apos;s ability to reproduce the
      location of the enhancements is due to the fact that this model
      reproduces the pattern of the convective events occurrence on a daily
      basis during the summer of 2006, even though it does not well
      represent the relative distribution of lightning intensities. By
      imposing an updated lightning NO production value of 520 mol NO/Flash,
      we decrease the bias between TES and GEOS-Chem over the US
      in July 2006 by 40%.</abstract>
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</article>

