SGER: Photoacoustic Measurement of Aerosol Light Absorption for the Coastal Stratocumulus Imposed Perturbation Experiment

这一探索性研究小额赠款项目包括在海岸层积云强制扰动实验(C-STRPE)期间使用一种新型光声(PA)仪器在高空直接测量可见范围(678纳米)的气溶胶光吸收。C-STRIPE的空中测量将由海军跨学科远程驾驶飞机研究中心办公室(ONR/CIRPAS)的双水獭研究飞机进行，将于2003年7月在加利福尼亚州蒙特利海岸附近进行为期三周的测量。飞行还将在污染严重的加州大陆地区圣华金河谷上空进行，以检查烟雾和城市/工业羽流产生的黑碳。通过将这一新功能添加到C-STRIPE机载仪器套件中，P.I.将提供一种独特的高空气溶胶光吸收的定性测量，以评估辐射强迫和云动力学方面的气溶胶-云相互作用。还将在该PA仪器与其他两种不同技术之间进行一项重要的空中比对实验，以测量由于气溶胶引起的环境大气光吸收。这项研究的结果应该会增进对雾霾和/或云层中气溶胶对辐射强迫的影响的气候强迫的理解--目前限制全球气候模型代表性的主要不确定性。

This Small Grants for Exploratory Research (SGER) project involves direct measurements aloft of aerosol light absorption in the visible range (678 nm) using a novel photoacoustic (PA) instrument during the Coastal STRatocumulus Imposed Perturbation Experiment (C-STRIPE). Airborne measurements for C-STRIPE will be made from the Office of Naval Research Center for Interdisciplinary Remotely-Piloted Aircraft Studies (ONR/CIRPAS) Twin Otter research aircraft over three weeks in July 2003 off the coast of Monterey, California. Flights will also be performed over the heavily polluted San Joaquin Valley, California continental area to examine black carbon emanating from smoke and urban/industrial plumes. By addition of this new capability to the C-STRIPE airborne instrument suite the P.I. will provide a unique qualitative measurement of aerosol light absorption aloft to assess aerosol-cloud interactions in terms of radiative forcing and cloud dynamics. An important airborne intercomparison experiment will also be conducted between this PA instrument and two other distinct techniques for measuring ambient atmospheric light absorption due to aerosols. Results from this study should increase understanding of climate forcing by aerosol impacts on radiative forcing in haze and/or cloud layers - major uncertainties currently limiting the representativeness of global climate models.