Interactions of Aerosols, Marine Boundary Layer Clouds, and Precipitation During the VOCALS-Regional Experiment: Observations, Modeling, and Large-scale Model Assessment

VOCALS 区域实验期间气溶胶、海洋边界层云和降水的相互作用：观测、建模和大型模型评估

• 批准号: 1242639
• 负责人: Robert Wood
• 金额: $ 53.19万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-11-01 至 2016-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1242639&HistoricalAwards=false
• 关键词: Interactions; Aerosols; Marine; Boundary; Layer; Interactions; Aerosols; Marine; Boundary; Layer

This supports analysis of collected during the Variability of the American Monsoon Systems Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx, or simply REx). The VOCALS-REx field campaign took place over the Southeast Pacific Ocean (SEP) during Oct-Nov 2008, and was designed to improve understanding of interactions between aerosols, marine boundary layer (MBL) clouds, and precipitation over the region. The SEP is climatically important because it is home to the world's largest subtropical stratocumulus cloud deck, which cools the climate by reflecting solar radiation back to space. Thus interactions between clouds, aerosols, and precipitation in the SEP can have an important climatic effect by modulating cloud cover and cloud albedo. The research here continues two key REx themes: research on Pockets of Open Cells (POCs), which are openings in the stratocumulus deck in which clouds have presumably dissipated due to drizzle formation; and research on offshore transport of pollution and its effect on SEP cloud and aerosol characteristics. Observations of cloud droplet concentration taken during REx using the NCAR C-130 aircraft show large "hook" features extending offshore from the Chilean coast, which may be due to high concentrations of cloud condensation nuclei (CCN) associated with pollution from copper smelters and coastal conurbations.Research performed under this grant uses REx data, much of which has not been previously analyzed, as well as data from global atmospheric model simulations prepared for the VOCALS Model Assessment (VOCA), together with numerical experiments using a large-eddy simulation (LES) code, to develop a better understanding of POCs, hooks, and SEP aerosol-cloud interactions. Three broad science questions are addressed: 1) How important is the free-tropospheric aerosol source to CCN and cloud droplet number concentrations in the VOCALS region, especially in the oceanic region over 500 km away from coastal pollution sources? 2) Is the precipitation sink for aerosols a major positive feedback on CCN differences between clean and polluted regions, in particular for hooks and POCs? 3) Can regional and global chemistry-climate models that include some representation of aerosol-cloud- precipitation interactions realistically simulate hooks and POCs?Beyond its scientific merit, the project has broader impacts due to the important role of SEP clouds in regulating earth's climate. A better understanding of the role of aerosol-cloud interactions in determining cloud cover and cloud brightness could thus lead to improved understanding and predictions of climate variability and change. In addition, the project supports two graduate students, thereby providing for the next generation of the scientific workforce in this area.

这支持对在美国季风系统的可变性过程中收集的分析，海云 - 大气研究区域实验（Vocals-Rex或Simpple Rex）。人声霸权田间运动发生在2008年10月至11月的东南太平洋（SEP）上，旨在提高对气溶胶，海洋边界层（MBL）云之间的相互作用以及该地区的降水量的理解。 SEP在气候上很重要，因为它是世界上最大的亚热带地层云甲板的所在地，该甲板通过将太阳辐射反射回太空来冷却气候。因此，SEP中云，气溶胶和降水之间的相互作用可以通过调节云覆盖物和云反照率具有重要的气候效应。这里的研究继续了两个关键的雷克斯主题：开放细胞口袋（POC）的研究，它们是层状甲板中的开口，其中云由于毛毛雨的形成大概消散了。以及对污染的海上运输及其对SEP云和气溶胶特征的影响的研究。 使用NCAR C-130飞机在REX期间进行的云滴浓度的观察显示出很大的“钩子”特征，从智利海岸延伸的海上延伸的特征可能是由于高浓度的云凝结核（CCN）引起的与铜冶炼厂和沿海conurbations相关的污染与此基金的模型相关。模型评估（VOCA）以及使用大型仿真（LES）代码的数值实验，以更好地了解POC，钩子和SEP Aerosol-Cloud相互作用。 解决了三个广泛的科学问题：1）自由球层气雾剂源对人声区域中CCN和云滴数量的浓度有多重要，尤其是在距离沿海污染源500公里以上的海洋地区？ 2）气溶胶的降水量是否对清洁区域和污染区域之间的CCN差异，尤其是钩子和POC之间的差异有主要的积极反馈？ 3）区域和全球化学气候模型是否可以包括气溶胶 - 云 - 降水相互作用的某些表示形式，实际上模拟了钩子和POC？除了其科学优点之外，由于SEP云在调节地球气候中的重要作用，该项目具有更大的影响。 因此，更好地理解了气溶胶云相互作用在确定云覆盖和云亮度中的作用，可能会提高人们对气候变化和变化的理解和预测。 此外，该项目还支持两名研究生，从而为该领域的下一代科学劳动力提供了支持。