Perennial observations of molecular hydrogen (Hb>2 b>) at a suburban site in Switzerland
- 作者：M. Steinbacher ; A. Fischer ; M.K. Vollmer ; B. Buchmann ; S. Reimann ; C. Hueglin
- 关键词：e="mml26">e="text-decoration ; none ; color ; black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml26&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=2e557eda0389b6bc57a05dcc5a84abf3" title="Clic
- 刊名：Atmospheric Environment
- 出版年：2007
- 期刊代码：11_13522310
- 类别：env
- 出版时间：March 2007
- 卷：41
- 期：10
- 页码：2111-2124
- 文件大小：3513 K
摘要
Semi-continuous measurements of atmospheric molecular hydrogen e="mml14">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml14&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=1c284689570ee956078ec9e6152ef97a" title="Click to view the MathML source">(Hb>2 b>) and carbon monoxide (CO) were performed at a suburban sampling site in Switzerland from November 2002 to February 2005. The presented data provide information about time series, seasonal and diurnal cycles as well as sources and sinks in a suburban environment. Such records become increasingly important for the assessment of the effects of a possible future hydrogen economy on the environment. No significant trend of background e="mml15">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml15&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=9b07e1010bdf001eae6b2d238c58e54a" title="Click to view the MathML source">Hb>2 b> concentrations could be observed for the considered period. Seasonal cycles show the expected pattern with maxima in winter and minima in summer and autumn. When extracting the background e="mml16">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml16&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=97e305d8dfdffde234e588dedf1ad958" title="Click to view the MathML source">Hb>2 b> mixing ratios, the absolute levels as well as the seasonal amplitude agree well with literature data from semi-rural and remote sites. The e="mml17">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml17&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=68429fb7e09bd5a80a15c6e1974803e9" title="Click to view the MathML source">Hb>2 b> dry deposition velocity for summer days with low winds is estimated to be between e="mml18">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml18&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=33d01154dbbba6e68fdce8bd3f81949a" title="Click to view the MathML source">0.5×10-4 to e="mml19">. Diurnal cycles are dominated by e="mml20">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml20&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=580a9532c4e6fae19e30cd1e2391feb7" title="Click to view the MathML source">Hb>2 b> emissions from nearby traffic. The influence of traffic-related emissions is also corroborated by a high e="mml21">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml21&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=ebb531b73038431da5461ffad8084955" title="Click to view the MathML source">Hb>2 b> to CO correlation. Typical molar e="mml22">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml22&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=dd878f172cddcce68cca0f684d1b665a" title="Click to view the MathML source">Hb>2 b> to CO ratios from traffic were found to be 0.33 on a molar basis (ppb/ppb). A reduction of 37–62%in European anthropogenic e="mml23">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml23&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=421ac0f65361da2786a3a36b3bb39b6e" title="Click to view the MathML source">Hb>2 b> emissions is estimated for a period covering the last 25 years. Since the ambient e="mml24">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml24&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=d0d4fc45c7fb07907c3abf7978002689" title="Click to view the MathML source">Hb>2 b> concentration did not decline during the same period, other simultaneous changes of sinks or sources of e="mml25">e="text-decoration:none; color:black" href="/science?_ob=MathURL&_method=retrieve&_udi=B6VH3-4MM95WG-2&_mathId=mml25&_user=10&_cdi=6055&_rdoc=9&_acct=C000050221&_version=1&_userid=10&md5=cf820da2c3067f234bd4af0968477acb" title="Click to view the MathML source">Hb>2 b> must have compensated this reduction.