Investigation of the Aerosol Indirect Effect on Ice Clouds and its Climate Impact Using A-Train Satellite Data and a GCM (General Circulation Model)

本研究的目的是利用一般环流模式（GCM）和卫星资料，通过气溶胶、云、辐射和动力过程之间的相互作用，提高我们对气溶胶间接效应的理解，重点是冰云及其对气候模式和模拟的影响。这项研究的方法将包括观测分析和气候模拟。从A-Train卫星观测中获取的云和气溶胶数据将被分析并用于气候模拟模拟。新的努力将包括气溶胶对冰晶有效尺寸的第一个间接影响的参数化，用于基于A-Train卫星数据对应于“清洁”和“污染”云的气候模型。UCLA大气GCM （AGCM）将用于研究大气系统对气溶胶第一间接效应辐射强迫的响应。这项研究是首次尝试利用与a -train卫星数据相关的GCM来量化气溶胶间接效应对气候的影响。具体而言，该项目将：(1)发展气溶胶对冰晶有效尺寸的间接影响的参数化，以应用于gcm；(2)在气候模式中量化气溶胶第一间接效应的辐射强迫；(3)确定气溶胶间接效应与气溶胶直接辐射强迫的相对重要性；(4)研究污染云对与气溶胶相关的全球和区域气候变化的直接和间接影响；(5)对现有的基于简化冰微物理的气溶胶对冰云间接效应的参数化方法进行了研究，并探索了辅助这类参数化的卫星数据。这项研究的更广泛影响包括对气溶胶气候效应的深入了解，以及通过减少gcm中气溶胶相关的不确定性，可能改善气候模拟和预测。研究生将得到培训和支持。

The objective of this study is to improve our understanding of the aerosol indirect effect with a focus on ice clouds and its impact on climate modeling and simulation through the interactions among aerosols, clouds, radiation, and dynamical processes, using a general circulation model (GCM) and satellite data. The approach of this research will involve both observational analysis and climate modeling. Cloud and aerosol data retrieved from A-Train satellite observations will be analyzed and employed in climate modeling simulations. The new endeavor will include parameterization of the aerosol first indirect effect on ice crystal effective size for use in climate models based on the A-Train satellite data corresponding to 'clean' and 'polluted' clouds. The UCLA atmospheric GCM (AGCM) will be employed to investigate the response of the atmosphere system to the radiative forcings of the aerosol first indirect effect. This study represents one of the first attempts to quantify the climate impact of the aerosol indirect effect using a GCM in connection with A-train satellite data.In particular, the project will: (1) develop a parameterization of the aerosol first indirect effect on ice crystal effective size for application to GCMs; (2) quantify the radiative forcing of the aerosol first indirect effect in a climate model; (3) identify the relative importance of the aerosol indirect effect with the presence of aerosol direct radiative forcing; (4) investigate the impact of polluted clouds on global and regional climate change associated with the aerosol direct and indirect effects; and (5) examine the existing aerosol indirect effect parameterization on ice clouds that has been developed on the basis of simplified ice microphysics and explore the satellite data to assist in this type of parameterization. Broader impacts of this research include an advanced understanding of climatic effects of aerosols and potentially improved climate simulations and projection by reducing aerosol related uncertainties in GCMs. A graduate student will be trained and supported.