RAPID: PAEROS ChArMEx Mountain Experiment (PACMEx)

地中海地区已被确定为未来气候变化预测的热点，因为到本世纪之交，水文循环的预期变化将影响数百万人的水资源。模式模拟表明，随着环境温度的上升，夏季降水显著减少；此外，降水的更大变异性可能会增加山洪、干旱和热浪的强度。然而，到目前为止，大多数模型都没有考虑到地中海盆地气溶胶的影响，其主要来源包括撒哈拉沙尘、生物质燃烧和人为排放。最近由PI领导的空中研究表明，来自欧洲和非洲的气雾源被输送到对流层下部，最远可达6公里。由于其复杂的垂直分布，捕捉这些源的可变性和量化这些源对辐射预算的贡献(直接和间接影响)是一项挑战。根据这项快速奖励，将于2013年6/7月在科西嘉岛的一个山区部署小型气溶胶观测系统(PAEROS；便携式气溶胶观测系统)，以补充其他地面和空中活动，并测量气溶胶的物理和光学特性、云凝聚核(CCN)光谱、辐射通量和气象参数。具体而言，该项目涉及以下科学目标：(1)调查地中海盆地上空气溶胶的来源和汇，以确定欧洲排放、撒哈拉沙尘和在发生大部分输送的边界层上方燃烧生物质的贡献；(2)加强空中和其他地面测量的观测网络(在边界层)，以描述自由对流层和边界层之间的气溶胶-云相互作用和混合；(3)利用吸湿性研究气溶胶在输送过程中的演变，并量化转变的特征时间；以及(4)通过在偏远山区使用太阳能电池板阵列和风力发电长期运行观测系统，展示PAEROS的技术能力。提高对水文循环的认识具有巨大的社会影响。该项目还通过博士生和博士后的直接参与，促进了法国和美国研究机构之间的国际合作。

The Mediterranean Region has been identified as a hot-spot in future climate change projections, as expected changes in the hydrological cycle will affect the water resources for millions of people by the turn of the century. Model simulations suggest a significant decrease in the summer precipitation along with a rise in ambient temperature; in addition, a greater variability in precipitation will likely increase the intensity of flash floods, droughts, and heat waves. Until now, however, most models have not accounted for the impacts of aerosol in the Mediterranean Basin, whose major sources include Saharan dust, biomass burning and anthropogenic emissions. Recent airborne studies led by the PI indicate that aerosol sources from Europe and Africa are transported throughout the lower troposphere up to 6 km. Because of their complex vertical distribution, it is a challenge to capture the variability and quantify the contribution of these sources to the radiative budget (both direct and indirect effects).Under this RAPID award, a miniaturized aerosol package (PAEROS; Portable AERosol Observing System) will be deployed at a mountain site in Corsica for six weeks in June/July 2013 to complement other ground-based and airborne activities and measure aerosol physical and optical properties, Cloud Condensation Nuclei (CCN) spectra, radiative fluxes and meteorological parameters. Specifically, this project addresses the following science objectives:(i) Investigate the sources and sinks of aerosol over the Mediterranean Basin to identify the contribution of European emissions, Saharan dust and biomass burning above the boundary layer where much of the transport occurs; (ii) Enhance an observational network of airborne and other ground-based measurements (in the boundary layer) to characterize aerosol-cloud interactions and mixing between the free troposphere and boundary layer; (iii) Use hygroscopicity to study the evolution of aerosol during transport and quantify the characteristic time of the transformation; and (iv) Demonstrate the technical capability of PAEROS by operating the observing system at a remote mountain site with a solar panel array and wind power for an extended period. Improved understanding of the hydrological cycle has tremendous societal impacts. This project also fosters international collaboration between French and American research institutions through direct involvement of PhD students and post-docs.