Quantifying the Effect of Surface Heating and Aerosols on Sea-Breeze Forced Deep Convection

在热带地区，深层对流很大程度上受地表温度变化的控制。海洋区域岛屿对地表温度变化的设定具有重要的控制作用。深层对流的形成通常是由海风控制的，海风会迫使空气大幅度向上垂直运动。数值天气预报模式难以纳入不同大小和地形的海岛海风所引起的空气环流及其在增加气溶胶排放中的作用。气溶胶与对流活力之间的相互作用，特别是在岛屿上空，了解甚少。与海洋上空的气流相比，岛屿上空的对流可能含有相对较高的气溶胶浓度，这为形成云的水凝结提供了核。研究旨在确定海风对流的发生、机制和环境条件，地形对海岛海风强迫对流的影响，气溶胶-海风相互作用对海岛对流强度的影响。该项目将让本科生通过学习高性能计算和开发解决问题和科学分析的严格方法来参与前沿研究。此外，由于云的形成和降水预报仍然是天气预报的难点之一，因此本研究获得的知识可能有助于了解对流云过程。研究小组将使用云解析数值模型、正演模拟卫星模拟器和卫星/雷达观测来研究以下物理假设：1)海风-气溶胶相互作用控制深层对流的产生和强度；2)含有岛屿气溶胶的加热岛屿空气主要通过海风或冷池动力学触发深层对流。数值结果将用于应用卫星数据模拟器单元（SDSU）模拟卫星观测；将实际卫星数据与SDSU模拟输出进行比较，将在该项目的观测和建模部分之间架起一座桥梁。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In the tropics, deep convection is largely controlled by surface temperature variations. Islands in ocean regions exert significant control on the setting of the surface temperature variation. The initiation of deep convection is often controlled by sea breezes, which force large upward vertical air motions. Numerical weather forecast models have difficulty to incorporate air circulations caused by island sea breezes with various sizes and topographies and their role in enhancing aerosol emissions. The interaction between aerosols and convective vigor particularly over islands is poorly understood. Convection over islands could contain relatively high aerosol concentration compared to air flows over sea, which provides nuclei for water to condense on in forming clouds. The study is to determine the occurrence, mechanisms, and environmental conditions of sea breeze convection initiation, the effect of orography on sea breeze forced convection over islands, and the effect of aerosol-sea breeze interaction on convective vigor over islands. The project will involve undergraduate students to participate in the cutting-edge research by learning high performance computing and developing a rigorous approach to problem solving and scientific analysis. Furthermore, because cloud formation and precipitation forecast remain one of difficult problems in weather forecasting, the knowledge gained from this study may shed light on convective cloud processes. The research team will use a hierarchy of cloud resolving numerical models, forward modeling satellite simulators, and satellite/radar observations to investigate the following physical hypotheses: 1) sea-breeze-aerosol interactions control both initiation and intensity of deep convection; 2) heated island air that contains island aerosols triggers deep convection principally via sea-breeze or cold-pool dynamics. The numerical result will be used to simulate satellite observations by applying the Satellite Data Simulator Unit (SDSU); comparisons of actual satellite data with SDSU simulated outputs will provide a bridge between the observational and modeling components of the project.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.