Reconciling Models and Observations of Aerosol Indirect Effects: A 2004 Field Study in the Northeastern United States

气溶胶对云的影响（气溶胶间接效应）与辐射传输和气候强迫有着至关重要的关系。气溶胶的间接影响仍然知之甚少，这加剧了严重缺乏高质量的实验场数据，需要产生准确的参数化和适当的约束分析模型。该项目包括一系列的现场实验的办公室的海军研究中心的跨学科遥控飞机研究（ONR/CIRPAS）双水獭研究飞机（与校外资金从ONR确认）的一部分，洲际运输和化学转化（ITCT）项目在2004年夏季在美国东北部。加州理工学院（CalTech）小组将从双水獭收集各种气象、气溶胶微物理和化学数据，并进行详细分析和三维辐射传输建模。该项目的最终目标是进行一项强有力的闭合研究，将辐射收支中的测量项与气溶胶和云特性中的预测项进行比较。考虑到涉及低空云的更先进的气溶胶-云相互作用参数化，将导致在大气环流模式框架下在各种尺度上对气溶胶-云-辐射过程进行更具代表性的建模。这项研究的结果将为我们对云和气候的理解提供新的数据和更好的见解，减少目前与量化当前和预测未来气候变化相关的巨大不确定性。 更广泛的教育影响包括支持加州理工学院的一名博士后学者和两名研究生。将通过一个设在格鲁吉亚理工学院的研究所将实地数据纳入大气环流模型气溶胶-云相互作用模块，再资助一名研究生。

The effect of aerosols on clouds (aerosol indirect effect) has critically important relevance to radiative transfer and climate forcing. The aerosol indirect effect is still poorly understood, this aggravated by a severe paucity of high quality experimental field data required to produce accurate parameterizations and properly constrain analytical models. This project involves a series of field experiments on the Office of Naval Research Center for Interdisciplinary Remotely-Piloted Aircraft Studies (ONR/CIRPAS) Twin Otter research aircraft (with extramural funding from ONR confirmed) as part of the Intercontinental Transport and Chemical Transformation (ITCT) project during summer 2004 over the Northeastern United States. The California Institute of Technology (CalTech) group will collect a variety of meteorological, aerosol microphysical and chemical data from the Twin Otter and follow with detailed analyses and three-dimensional radiative transfer modeling. The ultimate goal of this project is a robust closure study comparing measured terms in the radiation budget to predictions of those terms from aerosol and cloud properties. Taking into account more advanced aerosol-cloud interaction parameterizations involving low-altitude clouds will lead to more representative modeling of aerosol-cloud-radiation processes on a variety of scales under a general circulation model framework. Results from this study will provide new data and improved insight to our understanding of clouds and climate, reducing present large uncertainties related to quantifying current and predicting future climate change. Broader educational impacts include support for one postdoctoral scholar and two graduate students at CalTech. Through a subcontract to Georgia Institute of Technology to incorporate field data into a general circulation model aerosol-cloud interaction module an additional graduate student will be supported.