Collaborative Research: Evaluating the Influences of Aerosols on Low-level Cloud-precipitation Properties over Land and Ocean using Ground-based Observations and WRF Simulations

合作研究：利用地面观测和 WRF 模拟评估气溶胶对陆地和海洋低层云降水特性的影响

• 批准号: 1700796
• 负责人: Timothy Logan
• 金额: $ 8.52万
• 依托单位: Texas A&M University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1700796&HistoricalAwards=false
• 关键词: Collaborative; Research; Evaluating; Influences; Aerosols

Aerosol generation resulting from natural and anthropogenic activities is expected to have considerable, far-reaching effects on cloud development and the hydrologic cycle. Though the aerosol direct effect can simply be thought of as a reduction of incoming solar radiation reaching the Earth's surface, the aerosol indirect effect (AIE) involves a complex set of aerosol-cloud-precipitation interactions. These indirect effects include the alteration of cloud microphysical properties such as cloud lifetime, droplet size distribution, liquid water content and path, optical depth, and albedo. Precipitation processes will certainly be affected in numerous and at times, detrimental ways. Hence, there is a major impact to society as a whole due to a heavy dependence on the distribution of available water over a given region for public consumption, agriculture, and industrial purposes.Intellectual Merit:This research adopts a synergistic approach that uses the long-term ground-based observations and retrievals from the Southern Great Plains of the United States and Eastern North Atlantic Ocean regions to investigate the seasonal and diurnal variations of aerosol and clouds under the continental and maritime conditions, as well as compare their similarities and differences. Air parcel trajectory modeling will be conducted to identify the sources of air masses for the selected cases to investigate the AIEs over these two regions with additional WRF simulations. This study is important because it will aid to improve aerosol and cloud parameterizations as well as provide an in-depth understanding of aerosol-cloud-precipitation interactions in typical maritime and continental conditions. The following three scientific questions (SQs) will be investigated.SQ1: What are the similarities and differences of aerosol-cloud properties, as well as their interactions over ocean and land? SQ2: What are the indirect effects of aerosols on cloud microphysical properties? SQ3: How does wind shear enhance turbulent mixing and stimulate drizzle formation?Broader Impacts:This research will benefit society by helping to provide better support for the modeling of aerosol-cloud-precipitation interactions which will aid in researching the long-term distribution of available water by clouds and precipitation processes. The far-reaching goal of this project is to further reduce uncertainties in the climate modeling community by providing better constraints for seasonal and regional aerosol and cloud properties. Moreover, there will be plenty of opportunities to introduce aerosol-cloud interactions as "real world" examples in undergraduate and graduate geoscience courses where the students can not only investigate these examples as interdisciplinary class projects, but also improve upon current research techniques and develop their own theses and dissertation areas of focus.

由自然和人为活动产生的气溶胶预计将对云的发展和水文循环产生相当大的深远影响。虽然气溶胶直接效应可以简单地认为是减少到达地球表面的入射太阳辐射，但气溶胶间接效应（AIE）涉及一系列复杂的气溶胶-云-降水相互作用。这些间接影响包括云的微物理性质的改变，如云的寿命，液滴的大小分布，液态水的含量和路径，光学厚度，和反射率。降水过程肯定会受到许多影响，有时是有害的。因此，由于公共消费、农业和工业用途严重依赖特定地区可用水的分配，对整个社会产生了重大影响。知识产权优点：本研究采用协同方法，利用美国南部大平原和北大西洋东部地区的长期地基观测和反演，研究大陆和海洋条件下气溶胶和云的季节和日变化，并比较它们的相似性和差异性。将进行气团轨迹建模，以确定选定情况下的气团来源，并通过额外的WRF模拟调查这两个区域的AIE。这项研究是重要的，因为它将有助于改善气溶胶和云参数化，以及提供一个深入的了解气溶胶-云-降水在典型的海洋和大陆条件下的相互作用。将研究以下三个科学问题（SQs）：SQ 1：气溶胶-云特性的相似性和差异，以及它们在海洋和陆地上的相互作用？SQ 2：气溶胶对云微物理特性的间接影响是什么？SQ 3：风切变如何增强湍流混合并刺激毛毛雨的形成？更广泛的影响：这项研究将有利于社会，有助于为气溶胶-云-降水相互作用的建模提供更好的支持，这将有助于研究云和降水过程中可用水的长期分布。该项目的深远目标是通过为季节性和区域性气溶胶和云特性提供更好的约束，进一步减少气候模拟界的不确定性。此外，将有大量的机会介绍气溶胶-云的相互作用作为“真实的世界”的例子在本科生和研究生的地球科学课程，学生不仅可以调查这些例子作为跨学科的类项目，但也提高了目前的研究技术和发展自己的论文和论文的重点领域。

项目成果

Quantifying Long‐Term Seasonal and Regional Impacts of North American Fire Activity on Continental Boundary Layer Aerosols and Cloud Condensation Nuclei

• DOI: 10.1029/2020ea001113
• 发表时间: 2020-11
• 期刊: Earth and Space Science
• 影响因子: 3.1
• 作者: T. Logan;Xiquan Dong;B. Xi;Xiaojian Zheng;Yuanzu Wang;Peng Wu;Eleanor Marlow;James Maddux

Aerosol properties and their impacts on surface CCN at the ARM Southern Great Plains site during the 2011 Midlatitude Continental Convective Clouds Experiment

• DOI: 10.1007/s00376-017-7033-2
• 发表时间: 2018-01
• 期刊: Advances in Atmospheric Sciences
• 影响因子: 5.8
• 作者: T. Logan;Xiquan Dong;B. Xi