CAREER: The Upstream Impacts of Mountains on Frontal Precipitation Using Olympic Mountain Experiment (OLYMPEX) Observations

该奖项支持研究山区降水的发展。当天气系统被迫越过或绕过山区地形时，经常会出现降雨量和降雪量增加的情况，这严重影响了华盛顿州奥林匹克山等地区的供水，但也增加了洪水、雪崩和泥石流等灾害的风险。在某些条件下，这种降水增强的位置和强度可以改变，这种地形引起的增强发生在山脉本身上游的距离。量化这种上游降水增强是如何以及在何处发生的，以及它在快速变化的条件下如何演变，对于完整了解这些天气系统如何为一个地区提供降水，以及更准确地量化系统与地形相互作用所带来的不断变化的天气相关危害至关重要。通过全面的实地观测和高分辨率数值模拟，该项目将量化上游增强发生的条件，并确定导致快速演变的大气流动增强的机制。该项目将与一个整体的指导和研究经验计划的发展，以支持学生从两年制大学课程的转移。通过全面的导师模式，该计划将发展跨机构的关系，同时也提供全年的研究，沟通技能建设和专业发展的机会，以支持学生的道路进入地球科学。该项目使用分析的高分辨率雷达数据和探测收集在美国国家航空航天局-国家科学基金会奥林巴斯现场活动，业务数据从国家气象局WSR-88 D雷达和NWS Quillayute，WA探空站，和免费的高分辨率数值模拟，以量化锋面降水过程是如何独特地改变逆风的华盛顿州的奥林匹克山脉。主要任务将是通过对业务雷达数据的统计分析，确定山区上游地形增雨的首选区域，通过高分辨率多普勒分析和数值模拟，量化上游水流转向的变化和演变，并确定低-水平风和大气稳定性扩大了地形增强的范围，以及这如何影响锋面环流和降水，通过对地面和卫星的详细案例研究分析，基于雷达这项研究将有助于对锋面和其他高度可变的大气流与孤立山脉的相互作用有新的认识，这对了解山区岛屿周围地形增强降水的分布和演变具有重要意义。该奖项反映了NSF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。

This award supports research to study the development of precipitation over mountainous terrain. Increased rainfall and snowfall often occur when weather systems are forced to go over or around mountainous terrain, significantly impacting the availability of water for regions such as the Olympic Mountains of Washington State, but also increasing the risk of hazards such as flooding, avalanches and mudslides. Under some conditions, the location and intensity of this intensified precipitation can change, with this terrain-induced enhancement occurring at distances upstream of the mountains themselves. Quantifying how, and where, this upstream precipitation enhancement occurs and how it evolves in rapidly changing conditions is crucial to completing the full picture of how these weather systems provide precipitation to a region, as well as more accurately quantifying the evolving weather-related hazards that come with the system interacting with terrain. Through comprehensive field observations and high-resolution numerical simulations, this project will quantify the conditions where this upstream enhancement occurs and identify the mechanisms that lead to this enhancement in rapidly evolving atmospheric flows. This project will coincide with the development of a holistic mentoring and research experience program to support the transfer of students from two-year college programs. Through a comprehensive mentorship model, this program will develop cross institutional relationships while also providing year-round research, communication skill building, and professional development opportunities to support students’ path into geosciences.This project use analysis of high-resolution radar data and soundings collected during NASA-NSF OLYMPEX field campaign, operational data from the National Weather Service WSR-88D radars and NWS Quillayute, WA sounding station, and complimentary high-resolution numerical simulations to quantify how frontal precipitation processes are uniquely altered upwind of the Olympic Mountains of Washington State. The main tasks will be to identify the preferred regions of orographic precipitation enhancement upstream of the mountains through statistical analysis of operational radar data, to quantify the variability and evolution of upstream flow diversion through high-resolution Doppler analysis and numerical simulations, and to determine how variations in low-level winds and atmospheric stability extend the reach of the orographic enhancement and how this affects frontal circulations and precipitation through detailed case study analysis of ground-based and satellite-based radars. This research will contribute new understanding about the interaction of fronts and other highly variable atmospheric flows with isolated mountain ranges, which has significant implications for understanding the distribution and evolution of orographically-enhanced precipitation around mountainous islands.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.