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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACP</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACP</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7324</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/acp-7-4249-2007</article-id>
<title-group>
<article-title>First direct observation of the atmospheric CO&lt;sub&gt;2&lt;/sub&gt; year-to-year increase from space</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Buchwitz</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>Schneising</surname>
<given-names>O.</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>Burrows</surname>
<given-names>J. P.</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>Bovensmann</surname>
<given-names>H.</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>Reuter</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>Notholt</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Institute of Environmental Physics (IUP), University of Bremen FB1, Bremen, Germany</addr-line>
</aff>
<pub-date pub-type="epub">
<day>20</day>
<month>08</month>
<year>2007</year>
</pub-date>
<volume>7</volume>
<issue>16</issue>
<fpage>4249</fpage>
<lpage>4256</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>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/4249/2007/acp-7-4249-2007.html">This article is available from http://www.atmos-chem-phys.net/7/4249/2007/acp-7-4249-2007.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/4249/2007/acp-7-4249-2007.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/4249/2007/acp-7-4249-2007.pdf</self-uri>
<abstract>
<p>The reliable prediction of future atmospheric
CO&lt;sub&gt;2&lt;/sub&gt; concentrations and associated global climate change requires an
adequate understanding of the CO&lt;sub&gt;2&lt;/sub&gt; sources and sinks.
The sparseness of the existing surface measurement network limits current
knowledge about the global distribution of CO&lt;sub&gt;2&lt;/sub&gt; surface fluxes.
The retrieval of CO&lt;sub&gt;2&lt;/sub&gt; total vertical columns
from satellite observations
is predicted to improve this situation. Such an application however requires
very high accuracy and precision.
We report on retrievals of the column-averaged CO&lt;sub&gt;2&lt;/sub&gt; dry air mole fraction,
denoted XCO&lt;sub&gt;2&lt;/sub&gt;, from the near-infrared nadir spectral radiance and
solar irradiance measurements of the
SCIAMACHY satellite instrument between 2003 and 2005.
We focus on northern hemispheric large scale CO&lt;sub&gt;2&lt;/sub&gt; features
such as the CO&lt;sub&gt;2&lt;/sub&gt; seasonal cycle and show - for the first time - that the
atmospheric annual increase of CO&lt;sub&gt;2&lt;/sub&gt; can be directly observed
using satellite measurements of the CO&lt;sub&gt;2&lt;/sub&gt; total column.
The satellite retrievals are compared with
global XCO&lt;sub&gt;2&lt;/sub&gt; obtained from
NOAA&apos;s CO&lt;sub&gt;2&lt;/sub&gt; assimilation system CarbonTracker
taking into account the spatio-temporal sampling and
altitude sensitivity of the satellite data.
We show that the measured CO&lt;sub&gt;2&lt;/sub&gt; year-to-year increase
agrees within about 1 ppm/year with CarbonTracker.
We also show that the latitude dependent
amplitude of the northern hemispheric CO&lt;sub&gt;2&lt;/sub&gt; seasonal
cycle agrees with CarbonTracker within about 2 ppm
with the retrieved amplitude being systematically larger.
The analysis demonstrates that it is possible using
satellite measurements of the CO&lt;sub&gt;2&lt;/sub&gt; total column
to retrieve information on the atmospheric CO&lt;sub&gt;2&lt;/sub&gt;
on the level of a few parts per million.</p>
</abstract>
<counts><page-count count="8"/></counts>
</article-meta>
</front>
<body/>
<back>
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