Biogenic Bromine Production in Arctic Waters

该项目是对北极低层大气中有机溴化学的研究，特别是与对流层臭氧破坏有关的研究。据观察，在北极日出后不久，地表臭氧浓度从冬末的最大值下降到接近零，然后恢复到夏季的中等高值。也有强有力的证据表明，最小值的主要原因是有机溴气体产生的溴自由基的光解作用，然后与臭氧结合。化学途径是推测性的，人们对有机溴的来源知之甚少，但人们认为海洋来源是最有可能的。本研究通过在加拿大n.w.t.l Resolute的一个实地项目来解决前一个问题，收集和分析大气颗粒溴、无机和有机气态溴以及其他卤素（氯和碘），以评估它们在北极春季对对流层化学的可能贡献。支持臭氧和气象变量在国家海洋和大气管理局气候变化地球物理监测计划的巴罗天文台进行例行测量。从孵化的北极大型植物、浮游植物、冰藻和其他样品中收集和分析顶空气体的补充工作包括在一个单独资助的行动中。

This project is a study of organic bromine chemistry in the lower arctic atmosphere, particularly in relation to tropospheric destruction of ozone. It has been observed that shortly after the arctic sunrise, surface ozone concentrations decline from a late winter maximum to near zero before recovering to moderately high summer values. There is also strong evidence which implies that the primary cause for the minimum is the photolytic production of bromine radicals from organic bromine gases, which then combine with ozone. The chemical pathways are conjectural and little is known about the origins of the organic bromine, but it is believed that a marine source is the most probable. This study addresses the former question through a field program at Resolute, N.W.T., Canada, to collect and analyze atmospheric particulate bromine and both inorganic and organic gaseous bromine, as well as other halogens (chlorine and iodine) to assess their possible contributions to tropospheric chemistry during the arctic spring. Supporting ozone and meteorological variables are measured routinely at the Barrow Observatory of the Geophysical Monitoring for Climatic Change Program of the National Oceanic and Atmospheric Administration. The complementary effort to collect and analyze headspace gases from incubated arctic macrophyte, phytoplankton, ice algae, and other samples is included in a separately funded action.