Balloon-Borne In Situ Measurements of Aerosol Size and Concentration in the Mid Latitudes and Tropics

该项目将在中纬度的怀俄明州拉勒米继续并延伸气溶胶尺寸和浓度测量的垂直(地面至33公里)剖面。扩展测量将增加直径在0.03微米到0.15微米之间的气溶胶的新的尺寸分辨浓度测量，以及来自巴西纳塔尔的热带测量。拉勒米的气球测量将每两个月进行一次，纳塔尔的测量将在五年内每年进行一次。与剑桥大学的一项合作将允许对OCS(羰基硫化物)和SO2(二氧化硫)进行探索性测量，并结合一些气溶胶剖面。与丹麦气象研究所的另一项合作将为热带工作增加后向散射测量和建模方面的专门知识。在拉勒米进行持续的平流层气溶胶测量，对于明确地确定火山静止“背景”期间的平流层气溶胶水平是至关重要的。维持背景气溶胶水平所需的硫源以及对平流层气溶胶的扰动程度仍不确定。拉勒米记录是现存的关于平流层气溶胶的最长持续记录，因此处于有利地位来解决这些问题。对较小颗粒的新测量将解决在小颗粒控制表面积的背景期间，卫星和现场对气溶胶表面积的估计之间的持续差异。如果发生大型热带火山喷发，测量重点将转移到新鲜的火山羽流上。一年一度的热带测量是为了解决几个问题，例如，中高纬度尺寸分布在多大程度上表征了热带地区的气溶胶。热带测量还将测试热带平流层对新粒子形成和大颗粒层的早期测量，以及模型是否正确地解释了平流层气溶胶来源气体OCS/SO2。平流层气溶胶对大气和社会有广泛的影响。对全球平流层臭氧进行建模需要准确估计气溶胶表面积。大型火山喷发通过包括氯在内的非均相化学对臭氧产生直接影响，并对导致平流层变暖和对流层冷却的辐射产生直接影响。对流层气溶胶对辐射有更深远的影响，既有直接影响，也有通过对云层的影响。该项目将促进研究生和研究生的教学和培养。

This project will continue and extend vertical (surface to 33 km) profiles of aerosol size and concentration measurements at Laramie, Wyoming, a mid-latitude site. Extended measurements will add new size-resolved concentration measurements for aerosol between 0.03 and 0.15 micrometers in diameter, and tropical measurements from Natal, Brazil. The balloon-borne measurements will be conducted at bi-monthly intervals from Laramie and annually from Natal over five years. A collaboration with the University of Cambridge will permit exploratory measurements of OCS (carbonyl sulfide) and SO2 (sulfur dioxide) in conjunction with some aerosol profiles. An additional collaboration with the Danish Meteorological Institute will add backscattering measurements and modeling expertise to the tropical work. Continuing stratospheric aerosol measurements at Laramie is essential to help establish, unequivocally, stratospheric aerosol levels during volcanically-quiescent, "background," periods. The sulfur sources necessary to maintain background aerosol levels, and the extent of perturbations to stratospheric aerosol, are still uncertain. The Laramie record is the longest sustained record of stratospheric aerosol existent, and thus favorably positioned to address these questions. New measurements of smaller particles will address a persistent discrepancy between satellite and in situ estimates of aerosol surface area during background periods, when small particles control surface area. In the event of a large tropical volcanic eruption, the measurement focus will shift to the fresh volcanic plume. The annual tropical measurements are exploratory to address several questions, such as, how well do mid- and high latitude size distributions characterize aerosol in the tropics. The tropical measurements will also test earlier tropical stratospheric measurements of new particle formation and large particle layers, and whether models properly account for the stratospheric aerosol source gases OCS/SO2.Stratospheric aerosols have broad impacts on the atmosphere and thus on society. Modeling of global stratospheric ozone requires accurate estimates of aerosol surface area. Major volcanic eruptions produce direct impacts on ozone through heterogeneous chemistry, involving chlorine, and on radiation leading to stratospheric warming and tropospheric cooling. Tropospheric aerosols have even more far reaching impacts on radiation both directly and through their impact on clouds. This project will promote the teaching and training of graduate and postgraduate students.