Wind-driven Rainfall Microphysics: Raindrop Shape - Fall Velocity - Size Distribution under Wind Shear and Turbulence

风驱动降雨微物理：风切变和湍流下的雨滴形状 - 降落速度 - 尺寸分布

基本信息

批准号：
1741250
负责人：
Firat Testik
金额：
$ 43.06万
依托单位：
University of Texas at San Antonio
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-03-15 至 2025-02-28
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1741250&HistoricalAwards=false
关键词：
Wind driven Rainfall Microphysics Raindrop

项目摘要

Knowledge of the characteristics of raindrop size and shape is important for weather radar estimates of rainfall. Rainfall droplets can change in shape and speed as they fall to the ground, especially in situations where there are collisions with other droplets. This project will enable researchers to collect very high-resolution observations of raindrops and determine how they are affected by wind. Improved estimates of rainfall from weather radars will potentially impact flood forecasting and water resource management. The project also involves training and mentoring of early-career scientists, ensuring a diverse and highly capable future workforce.The research team will conduct an observational and analysis-based study to uncover the effect of wind on rainfall microstructure and whether microphysical quantities under the influence of wind can be predicted. Data for the study will come from a field site near UT-San Antonio, which includes the High-speed Optical Disdrometer (HOD) and other meteorological instruments. The project will address four main hypotheses: 1) Wind shear and turbulence induce flow/pressure field alterations/fluctuations around raindrops, 2) These alterations/fluctuations cause raindrop fall velocity deviations from predicted terminal values, 3) Broadening of the raindrop fall velocity distributions increases the raindrop-raindrop collision rates, and 4) Increased collision rates intensify drop size distribution evolution.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.

了解雨滴大小和形状的特征对于天气雷达估计降雨量非常重要。雨滴落到地面时形状和速度可能会发生变化，特别是在与其他雨滴发生碰撞的情况下。该项目将使研究人员能够收集非常高分辨率的雨滴观测结果，并确定它们如何受到风的影响。气象雷达对降雨量的改进估计将可能影响洪水预报和水资源管理。该项目还包括对早期职业科学家的培训和指导，确保未来拥有一支多元化、高能力的劳动力队伍。研究团队将进行一项基于观测和分析的研究，以揭示风对降雨微结构的影响以及微物理量是否受到影响。风的大小是可以预测的。该研究的数据将来自德克萨斯大学圣安东尼奥分校附近的一个现场，其中包括高速光学测速仪（HOD）和其他气象仪器。该项目将解决四个主要假设：1）风切变和湍流引起雨滴周围的流动/压力场改变/波动，2）这些改变/波动导致雨滴下落速度偏离预测的最终值，3）雨滴下落速度分布的拓宽增加了雨滴与雨滴的碰撞率，并且 4) 增加的碰撞率加剧了液滴尺寸分布的演变。该奖项反映了 NSF 的法定使命，并通过使用评估被认为值得支持基金会的智力价值和更广泛的影响审查标准。