Balloon-Borne Measurements of Vertical Profiles of Aerosols, Condensation Nuclei, and CloudCondensation Nuclei

该项目的重点是继续和扩大在怀俄明州拉勒米（41 N, 105 W）的垂直气溶胶剖面测量。平流层测量对于评估平流层气溶胶浓度在火山静止期或背景期维持的水平，从而了解平流层气溶胶水平在过去30年中是否受到人为（或自然）影响的扰动，具有重要意义。空中交通增加的影响尤其令人担忧。空中交通对气溶胶浓度的直接影响将通过寻找气球载测量与该地区空中交通尾迹的交集来研究。表征对流层气溶胶的直接影响和云凝结核（CCN）在全球气候模式中的间接影响是我们对全球热平衡理解的一个很大的不确定性来源，这可以通过对流层气溶胶和CCN的更精确测量来减少。持续的测量将包括从地表到30公里的凝结核（CN）和光学可探测的气溶胶（半径在0.15到2.0微米之间），以及从地表到大约13公里的凝结核。与过去一样，气球飞行频率将维持在每月一次左右。除了在拉勒米进行测量外，每年还将继续在新西兰兰黛进行测量（45‰）。将部署两个CCN计数器和一个新的多角度气溶胶仪器，首次提供CCN光谱的垂直剖面。第二个CCN计数器将在该项目下建造。这两台CCN仪器将允许在两个过饱和度下进行CCN测量，从而提供CCN光谱。多角度气溶胶仪器将用于对流层气溶胶粒子折射率的研究，该仪器目前正在其他资助下研制。为了补充这些测量，计划与另外两名研究人员合作。加州大学欧文分校的Darin Toohey博士将结合这些气溶胶测量，对Laramie的ClO/BrO进行大约季节性的剖面测量，以研究ClO/BrO在中纬度的非均匀过程。一位意大利同事计划用气球载激光散射仪来研究对流层粒子的折射率。

This project focuses on continuing and extending vertical aerosol profile measurements at Laramie, Wyoming (41░N, 105░W). The stratospheric measurements are important to assess the level at which stratospheric aerosol concentrations are maintained during volcanically quiescent, or background, periods, and thus to understand if the stratospheric aerosol level has been perturbed by anthropogenic (or natural) influences over the past 30 years. In particular, the impact of increasing air traffic is a concern. Direct effects of air traffic on aerosol concentration will be studied by looking for intersections of the balloon-borne measurements with the wakes of air traffic in the region. Characterizing the direct effects of tropospheric aerosol and the indirect effects of cloud condensation nuclei (CCN) in global climate models is a large source of uncertainty in our understanding of the global heat balance, which can be reduced through more refined measurements of tropospheric aerosol and CCN.The continuing measurements will consist of condensation nuclei (CN) and optically detectable aerosol (with a radius between 0.15 and 2.0 um), from the surface to 30 km, and CCN from the surface to about 13 km. The balloon flight frequency will be about once per month as it has been in the past. In addition to measurements in Laramie, yearly measurements from Lauder, New Zealand (45░S) will be continued. Two CCN counters and a new multi-angle aerosol instrument will be deployed, providing vertical profiles of CCN spectra for the first time. The second CCN counter will be built under this project. The two CCN instruments will allow CCN measurements at two supersaturations, thus providing CCN spectra. The multi-angle aerosol instrument, which is being developed under other support, will be used in studies of the index of refraction of tropospheric aerosol particles. To supplement these measurements, collaborations with two other investigators are planned. Dr. Darin Toohey, University of California at Irvine, will make approximately seasonal profile measurements of ClO/BrO from Laramie in conjunction with these aerosol measurements, in order to study mid latitude heterogeneous processing of ClO/BrO. An Italian colleague plans to participate with a balloon-borne laser scatterometer to investigate the index of refraction of tropospheric particles.