Collaborative Research: Topographic Influences on Extreme Warm-Season Precipitation

合作研究：地形对极端暖季降水的影响

• 批准号: 1854443
• 负责人: Alison Nugent
• 金额: $ 33.66万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1854443&HistoricalAwards=false
• 关键词: Collaborative; Research; Topographic; Influences; Extreme; Collaborative; Research; Topographic; Influences; Extreme

Extreme rainfall affects millions of people globally, yet our understanding and forecast skill of this high-impact weather phenomenon is limited. The Prediction of Rainfall Extremes Campaign in the Pacific (PRECIP, May-August 2020) field campaign aims to improve understanding of the multi-scale processes important for generating extreme rainfall in the moisture-rich environment of Taiwan and the western North Pacific. The overarching PRECIP hypothesis is that extreme rainfall results from an optimal combination of multi-scale ingredients in a moisture-rich environment, but different key ingredients and processes lead to strong vertical forcing and high rainfall intensity, strong horizontal forcing and long duration, or a mixture of both intense and sustained precipitation.Intellectual Merit:This project focuses on orographic influences on extreme rainfall, using a unique combination of radar and radiosonde observations on both sides of Taiwan's Central Mountain Range (CMR) to determine the role of steep terrain in enhancing both intensity and duration of rainfall through a combination of thermodynamic, dynamic, kinematic, and microphysical processes. The overall hypothesis is that terrain enhances both intensity and duration of extreme rainfall through increasing the magnitude of ingredients needed to produce heavy rainfall. In addition to promoting lifting and concentrating moisture, terrain modifies rainfall intensity and duration through changes in microphysical processes. In the subtropical environment of Taiwan, efficient warm-rain processes can produce high intensity convective rainfall, while ice-based processes become increasingly important for long-duration events dominated by stratiform precipitation. Additionally, results from TiMREX 2008 suggest that upslope tilting of relatively shallow convection along Taiwan's CMR can promote growth of precipitation-sized ice. Subsequent cold-pool generation leads to continuous growth of cells upstream and prolongs the duration of rainfall events along the CMR. PRECIP offers the opportunity to further explore the role of terrain, including the influence on microphysical processes, in producing extreme rainfall for a wide variety of events, both on the western slopes and along the data-sparse east coast of Taiwan. To test the above hypotheses, the study will use a combination of PRECIP data from multi-frequency dual-polarization Doppler radars (S-PolKa, SEA-POL), radiosondes, and models to explore terrain-influenced processes for diurnally-forced convection, mesoscale convective systems embedded within the Meiyu front, and tropical cyclones.Broader Impacts:An important broader goal of this investigation is to determine which of the key ingredients and processes identified for Taiwan extreme rainfall events are also relevant to orographic precipitation in other environments or locations. The team of three early-career female scientists brings a wealth of knowledge of observational field projects and terrain-influenced precipitation studies spanning a variety of global regimes, including warm-season rainfall in the Sierra Madre Occidentals, CMR, Andes, Rockies, and Himalayas, typical trade-wind flow, a tropical cyclone passing over Dominica, and cold-season rainfall over the Olympics. PRECIP will give an opportunity to investigate a wide variety of rain-producing events, both the windward and leeward sides of the mountain range. The findings from this project will have the potential to provide an updated understanding of extreme rainfall globally by building off an ingredients-based framework through unprecedented data collected in a wide variety of heavy rain events.This project is jointly funded by the Established Program to Stimulate Competitive Research (EPSCoR) and PREEVENTS, Prediction of and Resilience against Extreme Events program.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.

极端降雨会影响全球数百万的人，但是我们对这种高影响力天气现象的理解和预测技能受到限制。太平洋降雨极端运动的预测旨在提高对在台湾和北太平洋地区水分丰富的环境中产生极端降雨至关重要的多规模过程的理解。 The overarching PRECIP hypothesis is that extreme rainfall results from an optimal combination of multi-scale ingredients in a moisture-rich environment, but different key ingredients and processes lead to strong vertical forcing and high rainfall intensity, strong horizo​​ntal forcing and long duration, or a mixture of both intense and sustained precipitation.Intellectual Merit:This project focuses on orographic influences on extreme rainfall, using a unique combination of radar and台湾中央山脉（CMR）两侧的无线电体观测，以确定陡峭的地形在增强降雨强度和持续时间通过热力学，动态，运动学和微物理过程的结合。总体假设是，地形通过增加产生大降雨所需的成分的大小来增强强度和极端降雨的持续时间。除了促进提升和集中水分外，地形还通过微物理过程的变化改变了降雨强度和持续时间。在台湾的亚热带环境中，有效的暖雨过程可以产生高强度的对流降雨，而基于冰的过程对于以层状沉淀为主的长期事件变得越来越重要。此外，Timrex 2008的结果表明，沿台湾CMR沿着相对较浅的对流的上坡倾斜可以促进降水量冰的生长。 随后的冷池产生会导致上游细胞的持续生长，并延长沿CMR降雨事件的持续时间。 SEX提供了进一步探索地形作用的机会，包括对微物理过程的影响，在西部斜坡和台湾数据 - 帕克斯东海岸的各种事件中产生极端降雨。为了检验上述假设，该研究将使用多频性双极化多普尔多普勒雷达（S-Polka，Sea-Pol），Radiosondes和模型来探索昼夜对流的地形进程，Meisoscale对流系统在米尔特（Meiyu）的范围内以及特罗普（Tropical offor）。调查是为了确定台湾极端降雨事件确定的哪些关键成分和过程也与其他环境或位置的地形降水有关。 The team of three early-career female scientists brings a wealth of knowledge of observational field projects and terrain-influenced precipitation studies spanning a variety of global regimes, including warm-season rainfall in the Sierra Madre Occidentals, CMR, Andes, Rockies, and Himalayas, typical trade-wind flow, a tropical cyclone passing over Dominica, and cold-season rainfall over the Olympics.爆炸局将有机会调查山脉的迎风和背风侧的各种雨雨事件。该项目的发现将有可能通过在各种大雨事件中收集的前所未有的数据来建立基于成分的框架，从而提供对全球极端降雨的了解。该项目由既定计划共同资助，该项目由既定的计划共同资助，以刺激竞争性研究（EPSCOR）（EPSCOR）（EPSCOR）和对极端奖励的竞争力和稳定性。使用基金会的智力优点和更广泛的影响评估标准进行评估。