{"266211":{"#nid":"266211","#data":{"type":"news","title":"High Levels of Molecular Chlorine Found in Arctic Atmosphere","body":[{"value":"\u003Cp\u003EScientists studying the atmosphere above Barrow, Alaska, have discovered unprecedented levels of molecular chlorine in the air, a new study reports.\u003C\/p\u003E\u003Cp\u003EMolecular chlorine, from sea salt released by melting sea ice, reacts with sunlight to produce chlorine atoms. These chlorine atoms are highly reactive and can oxidize many constituents of the atmosphere including methane and elemental mercury, as well activate bromine chemistry, which is an even stronger oxidant of elemental mercury. Oxidized mercury is more reactive and can be deposited to the Arctic ecosystem.\u003C\/p\u003E\u003Cp\u003EThe study is the first time that molecular chlorine has been measured in the Arctic, and the first time that scientists have documented such high levels of molecular chlorine in the atmosphere.\u003C\/p\u003E\u003Cp\u003E\u201cNo one expected there to be this level of chlorine in Barrow or in polar regions,\u201d said \u003Ca href=\u0022http:\/\/huey.eas.gatech.edu\/\u0022\u003EGreg Huey\u003C\/a\u003E, a professor in the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology in Atlanta.\u003C\/p\u003E\u003Cp\u003EThe study was published January 12 in the journal \u003Ca href=\u0022http:\/\/dx.doi.org\/10.1038\/NGEO2046\u0022\u003E\u003Cem\u003ENature Geoscience\u003C\/em\u003E\u003C\/a\u003E and was supported by the National Science Foundation (NSF), part of the international multidisciplinary OASIS program.\u003C\/p\u003E\u003Cp\u003EThe researchers directly measured molecular chlorine levels in the Arctic in the spring of 2009 over a six-week period using chemical ionization mass spectrometry. At first the scientists were skeptical of their data, so they spent several years running other experiments to ensure their findings were accurate.\u003C\/p\u003E\u003Cp\u003EThe level of molecular chlorine above Barrow was measured as high as 400 parts per trillion, which is a high concentration considering that chlorine atoms are short \u2013lived in the atmosphere because they are strong oxidants and are highly reactive with other atmospheric chemicals. \u003Cbr \/\u003EMolecular chlorine concentrations peaked in the early morning and late afternoon, and fell to near-zero levels at night. Average daytime molecular chlorine levels were correlated with ozone concentrations, suggesting that sunlight and ozone may be required for molecular chlorine formation.\u003C\/p\u003E\u003Cp\u003EPrevious Arctic studies have documented high levels of oxidized mercury in Barrow and other polar regions. The major source of elemental mercury in the Arctic regions is coal-burning plants around the world. In the spring in Barrow, ozone and elemental mercury are often depleted from the atmosphere when halogens \u2014 chlorine and bromine \u2014 are released into the air from melting sea ice.\u003C\/p\u003E\u003Cp\u003E\u201cMolecular chlorine is so reactive that it\u2019s going to have a very strong influence on atmospheric chemistry,\u201d Huey said.\u003C\/p\u003E\u003Cp\u003EChlorine atoms are the dominant oxidant in Barrow, the study found. The area is part of a region with otherwise low levels of oxidants in the atmosphere, due to the lack of water vapor and ozone, which are the major precursors to making oxidants in many urban areas.\u003C\/p\u003E\u003Cp\u003EIn Barrow, snow-covered ice pack extends in every directly except inland. The ultimate source of the molecular chlorine is the sodium chloride in sea salt, Huey said, most likely from the snow-covered ice pack. How the sea salt is transformed into molecular chlorine is unknown.\u003C\/p\u003E\u003Cp\u003E\u201cWe don\u2019t really know the mechanism. It\u2019s a mystery to us right now,\u201d Huey said. \u201cBut the sea ice is changing dramatically, so we\u2019re in a time where we have absolutely no predictive power over what\u2019s going to happen to this chemistry. We\u2019re really in the dark about the chlorine.\u201d\u003C\/p\u003E\u003Cp\u003EScientists do know that sea ice is rapidly changing, Huey said. The sea ice that lasts from one winter to the next winter is decreasing. This has created a larger area of melted ice, and more ice that comes and goes with the seasons. This seasonal variation in ice could release more molecular chlorine into the atmosphere.\u003C\/p\u003E\u003Cp\u003E\u201cThere is definite climate change happening in the Arctic,\u201d Huey said. \u201cThat\u2019s changing the nature of the ice, changing the volume of the ice, changing the surface area and changing the chemistry of the ice.\u201d\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThis research is supported by the National Science Foundation under award number ATM-0807702, ARC-0806437 and ARC-0732556. Any conclusions or opinions are those of the authors and do not necessarily represent the official views of the NSF.\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ECITATION:\u003C\/strong\u003E Jin Liao, et al., \u0022High levels of molecular chlorine n the Arctic atmosphere,\u0022 (\u003Cem\u003ENature Geoscience\u003C\/em\u003E, January 2014). (\u003Ca href=\u0022http:\/\/dx.doi.org\/10.1038\/NGEO2046\u0022\u003Ehttp:\/\/dx.doi.org\/10.1038\/NGEO2046\u003C\/a\u003E).\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EResearch News\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EGeorgia Institute of Technology\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003E177 North Avenue\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EAtlanta, Georgia 30332-0181 USA\u003Cbr \/\u003E\u003Ca href=\u0022https:\/\/twitter.com\/GTResearchNews\u0022\u003E@GTResearchNews\u003C\/a\u003E\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EMedia Relations Contacts:\u003C\/strong\u003E Brett Israel (404-385-1933) (\u003Ca href=\u0022mailto:brett.israel@comm.gatech.edu\u0022\u003Ebrett.israel@comm.gatech.edu\u003C\/a\u003E) or John Toon (404-894-6986) (\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E)\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EWriter:\u003C\/strong\u003E Brett Israel\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EScientists studying the atmosphere above Barrow, Alaska, have discovered unprecedented levels of molecular chlorine in the air, a new study reports.\u0026nbsp;The study is the first time that molecular chlorine has been measured in the Arctic, and the first time that scientists have documented such high levels of molecular chlorine in the atmosphere.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Scientists studying the atmosphere above Barrow, Alaska, have discovered unprecedented levels of molecular chlorine in the air, a new study reports."}],"uid":"27902","created_gmt":"2014-01-13 10:15:52","changed_gmt":"2016-10-08 03:15:40","author":"Brett Israel","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2014-01-13T00:00:00-05:00","iso_date":"2014-01-13T00:00:00-05:00","tz":"America\/New_York"},"extras":[],"hg_media":{"266491":{"id":"266491","type":"image","title":"Snow-covered ice pack","body":null,"created":"1449244039","gmt_created":"2015-12-04 15:47:19","changed":"1475894953","gmt_changed":"2016-10-08 02:49:13","alt":"Snow-covered ice pack","file":{"fid":"198531","name":"barrow_sea_ice.jpg","image_path":"\/sites\/default\/files\/images\/barrow_sea_ice_0.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/barrow_sea_ice_0.jpg","mime":"image\/jpeg","size":81281,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/barrow_sea_ice_0.jpg?itok=Ml7Gs-lO"}},"266201":{"id":"266201","type":"image","title":"Measuring molecular chlorine in the Arctic atmosphere","body":null,"created":"1449244039","gmt_created":"2015-12-04 15:47:19","changed":"1475894953","gmt_changed":"2016-10-08 02:49:13","alt":"Measuring molecular chlorine in the Arctic atmosphere","file":{"fid":"198519","name":"jin_inbarrow.jpg","image_path":"\/sites\/default\/files\/images\/jin_inbarrow_0.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/jin_inbarrow_0.jpg","mime":"image\/jpeg","size":124937,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/jin_inbarrow_0.jpg?itok=GETO8ozG"}}},"media_ids":["266491","266201"],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"154","name":"Environment"}],"keywords":[{"id":"83461","name":"arctic atmosphere"},{"id":"831","name":"climate change"},{"id":"791","name":"Global Warming"},{"id":"83471","name":"greg huey"},{"id":"83451","name":"molecular chlorine"},{"id":"169620","name":"sea ice"}],"core_research_areas":[],"news_room_topics":[{"id":"71911","name":"Earth and Environment"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EBrett Israel\u003C\/p\u003E\u003Cp\u003E404-385-1933\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022mailto:brett.israel@comm.gatech.edu\u0022\u003Ebrett.israel@comm.gatech.edu\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":["brett.israel@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}