Thermodynamic Modification of Winter Storms in a Warmer Climate

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。冰暴由冻雨和/或冰粒组成，是一种极具破坏性的事件，可能导致危险的旅行条件和电力中断，导致经济损失和人员伤亡。气候变化对冰暴的影响还没有得到彻底的调查，冰暴对大气下部和地表温度的敏感程度也使情况变得复杂。这项工作将使用现有的气候模型模拟来解决在气候变暖的情况下，冰冻降水事件如何在地点、时间和大小上发生变化。该项目对可能正在处理基础设施加固问题的决策者具有实际影响。这位研究人员还计划从高中到研究生的教育和培训方面，以确保培养下一代科学家。该奖项是为了研究冰冻降水事件，包括冰球、冰雨和冰雨，以及如何根据21世纪末的气候变化改变它们的热力学。该项目的一个关键方面将是使用每小时4公里分辨率的国家大气研究中心(NCAR)天气研究和预报(WRF)模型伪全球变暖(PGW)模拟。PGW是一种通过施加与气候变暖一致的热变化来修改模型输入和边界条件的技术。用于检查气候变化的高分辨率动力学模型的计算成本非常高，因此WRF-PGW数据集的优势在于，它已经在非常高的空间和时间分辨率下进行，具有明显的对流并详细记录了偏差和限制。其他数据来源包括NOAA综合地面数据库、格网降水数据和再分析。提出了两个主要的研究问题：1)不同天气类型的冬季风暴的分布，以及它们对冰冻降水气候学、强度和持续时间的贡献，在变暖的气候中相对于历史基线的变化；2)随着21世纪末的热力学修改，包括热力和动力演变，以及系统内降水的分布，冬季风暴的结构、演变和形态是如何变化的(S)？这一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智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).Ice storms, which consist of freezing rain and/or ice pellets, are extraordinarily disruptive events that can cause hazardous travel conditions and power disruptions leading to economic losses and casualties. The impact of a changing climate on ice storms has not been thoroughly investigated, and it is complicated by how sensitive ice storms are to the temperature in the lower part of the atmosphere and at the surface. This work will use an existing climate model simulation to address how freezing precipitation events could change in location, timing, and size in a warmer climate. The project has practical impact to decision-makers who may be dealing with questions about hardening of infrastructure. The researcher also plans an education and training aspect that ranges from high school to graduate students, ensuring the training of the next generation of scientists.This award is for the study of freezing precipitation events, inclusive of ice pellets, freezing rain, and freezing drizzle, and how they may be altered with thermodynamics modifications consistent with late 21st century climate change. A key aspect of the project will be the use of the 4km resolution, hourly National Center for Atmospheric Research (NCAR) Weather Research and Forecast (WRF) model Pseudo Global Warming (PGW) simulation. PGW is a technique where a model’s input and boundary conditions are modified by imposing a thermal change consistent with a warmer climate. High-resolution dynamical models for the examination of climate change are very computationally expensive, so the advantage of the WRF-PGW dataset is that it has already been conducted at a very high spatial and temporal resolution, with explicit convection and detailed documentation of biases and limitations. Additional data sources include the NOAA Integrated Surface Database, gridded precipitation data, and reanalyses. Two main research questions are posed: 1) What is the distribution of winter storms of different synoptic ‘type’, and how does their contribution to the freezing precipitation climatology, intensity, and duration, change in a warmer climate versus the historical baseline, and 2) How does the structure, evolution, and morphology of winter storms change with late 21st century thermodynamic modification, including thermal and dynamic evolution, and distribution of precipitation phase within the system(s)?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.