Atmospheric Measurement Techniques www.atmos-meas-tech.net 1867-1381 1867-8548 3 1 2010 10.5194/amt-3-177-2010 http://www.atmos-meas-tech.net/3/177/2010/ http://www.atmos-meas-tech.net/3/177/2010/amt-3-177-2010.html http://www.atmos-meas-tech.net/3/177/2010/amt-3-177-2010.pdf 177 185 2010-02-09 A comparison of spectrophotometric and denuder based approaches for the determination of gaseous molecular iodine R. J. Chance 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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