Atmospheric Measurement Techniques Discussions www.atmos-meas-tech-discuss.net 1867-8610 2 5 2009 10.5194/amtd-2-2191-2009 http://www.atmos-meas-tech-discuss.net/2/2191/2009/ http://www.atmos-meas-tech-discuss.net/2/2191/2009/amtd-2-2191-2009.html http://www.atmos-meas-tech-discuss.net/2/2191/2009/amtd-2-2191-2009.pdf 2191 2215 2009-09-24 A comparison of spectrophotometric and denuder based approaches for the determination of gaseous molecular iodine R. J. Chance rjc508@york.ac.uk M. Shaw L. Telgmann M. Baxter L. J. Carpenter Department of Chemistry, University of York, York, YO10 5DD, UK Department of Chemistry, University of Münster, Münster, 48149, Germany The Food and Environment Research Agency, Sand Hutton, York, YO41 1LZ, UK The presence of molecular iodine in the atmosphere is thought to have implications for both climate and human nutritional health, but measurement of the gas at low concentrations requires technically demanding techniques that are not widely accessible. 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