An Investigation of Halogen Activation in the Lower Stratosphere and Upper Troposphere

该项目支持从气球平台测量平流层下部的卤素氧化物（ClO和BrO）。每年将在怀俄明州的拉勒米附近发射四个气球。一种新的轻型仪器将与光散射仪器（由美国大学Deshler教授建造）一起部署。怀俄明州）测量大气气溶胶的颗粒尺寸分布和数量密度。还将使用电化学电池测量臭氧。每年一次，将增加对二氧化碳和颗粒质量和组成的测量。 这项工作的目标是表征卤素氧化物的季节性变化，物种响应太阳光照，温度，痕量气体分布和气溶胶浓度的变化，并解决以下悬而未决的问题：（1）如何变化，季节性和年际，是今天在平流层下部的氯和溴的丰度？(2)这种变化有多少可以归因于异质化学和气溶胶表面积的变化？(3)颗粒大小、表面积和温度对多相化学和卤素活化的相对贡献是什么？(5)卷云会激活平流层下部和对流层上部的氯吗？

This project supports measurements of halogen oxides (ClO and BrO) in the lower stratosphere from balloon platforms. Four balloons per year will be launched near Laramie, WY. A new lightweight instrument will be deployed together with light scattering instruments (built by Prof. Deshler, U. Wyoming) that measure particle size distributions and number densities of atmospheric aerosols. Ozone will be also measured using electrochemical cells. Once per year, measurements of carbon dioxide and particle mass and composition will be added. The objectives of this work are to characterize the seasonal variability of the halogen oxides, species that respond to changes in solar illumination, temperature, trace gas distributions, and aerosol concentrations, and address the following outstanding issues: (1) How variable, seasonally and interannually, are abundances of ClO and BrO in the lower stratosphere today? (2) How much of this variability can be attributed to heterogeneous chemistry and to changes in aerosol surface area? (3) What are the relative contributions of particle size, surface area, and temperature to heterogeneous chemistry and halogen activation? (5) Do cirrus clouds activate chlorine in the lower stratosphere and upper troposphere?