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<article language="en">
	<journal>
		<journal_title>Atmospheric Measurement Techniques</journal_title>
		<journal_url>www.atmos-meas-tech.net</journal_url>
		<issn>1867-1381</issn>
		<eissn>1867-8548</eissn>
		<volume_number>2</volume_number>
		<issue_number>2</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/amt-2-573-2009</doi>
	<article_url>http://www.atmos-meas-tech.net/2/573/2009/</article_url>
	<abstract_html>http://www.atmos-meas-tech.net/2/573/2009/amt-2-573-2009.html</abstract_html>
	<fulltext_pdf>http://www.atmos-meas-tech.net/2/573/2009/amt-2-573-2009.pdf</fulltext_pdf>
	<start_page>573</start_page>
	<end_page>591</end_page>
	<publication_date>2009-10-23</publication_date>
	<article_title content_type="html">In-situ measurements of oxygen, carbon monoxide and greenhouse gases from Ochsenkopf tall tower in Germany</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>R. L. Thompson</name>
			<email>rthompson@bgc-jena.mpg.de</email>
		</author>
		<author numeration="2" affiliations="2">
			<name>A. C. Manning</name>
		</author>
		<author numeration="3" affiliations="3">
			<name>E. Gloor</name>
		</author>
		<author numeration="4" affiliations="1">
			<name>U. Schultz</name>
		</author>
		<author numeration="5" affiliations="1">
			<name>T. Seifert</name>
		</author>
		<author numeration="6" affiliations="1">
			<name>F. Hänsel</name>
		</author>
		<author numeration="7" affiliations="1">
			<name>A. Jordan</name>
		</author>
		<author numeration="8" affiliations="1">
			<name>M. Heimann</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Max Planck Institute for Biogeochemistry, Jena, Germany</affiliation>
		<affiliation numeration="2" content_type="html">School of Environmental Sciences, University of East Anglia, Norwich, UK</affiliation>
		<affiliation numeration="3" content_type="html">University of Leeds, Leeds, UK</affiliation>
	</affiliations>
	<abstract content_type="html">We present 2.5 years (from June 2006 to December 2008) of in-situ measurements of
CO&lt;sub&gt;2&lt;/sub&gt;, O&lt;sub&gt;2&lt;/sub&gt;, CH&lt;sub&gt;4&lt;/sub&gt;, CO, N&lt;sub&gt;2&lt;/sub&gt;O and SF&lt;sub&gt;6&lt;/sub&gt; mixing ratios sampled
from 23, 90 and 163 m above ground on the Ochsenkopf tower in the
Fichtelgebirge range, Germany (50&amp;deg;01&apos;49&quot; N, 11&amp;deg;48&apos;30&quot; E, 1022 m a.s.l.).
In addition to the in-situ measurements, flask samples are taken at
Ochsenkopf at approximately weekly intervals and are subsequently analysed
for the mixing ratios of the same species, as well as H&lt;sub&gt;2&lt;/sub&gt;, and the
stable isotopes, &amp;delta;&lt;sup&gt;13&lt;/sup&gt;C, &amp;delta;&lt;sup&gt;18&lt;/sup&gt;O in CO&lt;sub&gt;2&lt;/sub&gt;. The
in-situ measurements of CO&lt;sub&gt;2&lt;/sub&gt; and O&lt;sub&gt;2&lt;/sub&gt; from 23 m show substantial
diurnal variations that are modulated by biospheric fluxes, combustion of
fossil fuels, and by diurnal changes in the planetary boundary layer height.
Measurements from 163 m exhibit only very weak diurnal variability, as this
height (1185 m a.s.l.) is generally above the nocturnal boundary layer.
CH&lt;sub&gt;4&lt;/sub&gt;, CO, N&lt;sub&gt;2&lt;/sub&gt;O and SF&lt;sub&gt;6&lt;/sub&gt; show little diurnal variation even at 23 m
owing to the absence of any significant diurnal change in the fluxes and
the absence of any strong local sources or sinks. From the in-situ record,
the seasonal cycles of the gas species have been characterized and the
multi-annual trends determined. Because the record is short, the calculation
of the trend is sensitive to inter-annual variations in the amplitudes of
the seasonal cycles. However, for CH&lt;sub&gt;4&lt;/sub&gt; a significant change in the
growth-rate was detected for 2006.5–2008.5 as compared with the global
mean from 1999 to 2006 and is consistent with other recent observations of a
renewed increasing global growth rate in CH&lt;sub&gt;4&lt;/sub&gt; since the beginning of
2007.</abstract>
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