High Resolution air-sea coupling for downstream storm prediction

用于下游风暴预测的高分辨率海海耦合

基本信息

批准号：
1990060
负责人：
金额：
--
依托单位：
University of Reading
依托单位国家：
英国
项目类别：
Studentship
财政年份：
2017
资助国家：
英国
起止时间：
2017 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=studentship-1990060
关键词：
Resolution air sea coupling downstream

项目摘要

The structure of the storm-track is one of the key determinants of weather in the midlatitudes. Its climatological state depends on a complex non-linear balance between the upper level jet, turbulent baroclinic eddies and their associated eddy fluxes of heat and momentum, and forcing and dissipative processes. Getting the full structure of the storm track right in models is still one of the big challenges of weather and climate models. Recent work by the supervisor and collaborators has shown that northward heat fluxes due to weather systems over the Atlantic provide a strong steer to the downstream development and direction of the storm track. For example, high upstream heat fluxes are associated with a northward tilt of the storm track, a northward shift of the low level jet stream over our longitudes, and reduced periods between recurring storms. Independent theoretical support for most of the ingredients in this link have been published in the literature. This work is supported by a NERC project, and takes place in the context of several other research projects globally, such as WGNE-Drag, T-NAWDEX, and Primavera. Some preliminary work in the Primavera project at the University of Reading has also shown how very high resolution climate runs improve the upstream heat flux characteristics, the tilt of the storm track, and the statistical properties of the downstream storm tracks. In the present PhD project we will be examining the effects of high resolution coupling between the ocean and the atmosphere in the W. Atlantic region on the meridional heat fluxes in the atmosphere and the attendant effects on the storm track. For this work we will tie in with the second phase of UK Environmental Prediction programme, which aims to develop a high resolution (1km or less) coupled prediction model for the UK. Part of this programme is to assess the new science that such high resolution coupled models can address. In particular, heat exchange between the oceans and the atmosphere occurs at relatively small scales which are hard to resolve, but it is expected to contribute to the overall heat transport generated by the cyclone and by implication the expected downstream structure of the storm track. This project aims to use data from high resolution runs to establish the link between the ocean and the atmosphere at a wide range of scales and establish links to the downstream storm-track structure. We will be examining both statistical properties as well as specific time periods (case studies). The aim would be whether high resolution modelling of the coupling can improve our prediction of these atmospheric heat fluxes, and whether the hoped for improvement leads to a concomitant improvement of storm forecasts over the UK. The project will also make use of a newly developed technique to map the phase space of storm track development, where the interaction between upstream baroclinic growth rate and storm track activity can be followed in a dynamically consistent way.

风暴路径的结构是中纬度地区天气的关键决定因素之一。其气候状态取决于上层急流、湍流斜压涡流及其相关的热和动量涡流以及强迫和耗散过程之间复杂的非线性平衡。在模型中正确了解风暴路径的完整结构仍然是天气和气候模型的一大挑战。主管和合作者最近的工作表明，大西洋上空天气系统引起的向北热通量为风暴路径的下游发展和方向提供了强有力的指导。例如，上游高热通量与风暴路径向北倾斜、低空急流在经度上向北移动以及风暴复发周期缩短有关。该链接中大多数成分的独立理论支持已在文献中发表。这项工作得到 NERC 项目的支持，并在全球其他几个研究项目的背景下进行，例如 WGNE-Drag、T-NAWDEX 和 Primavera。雷丁大学 Primavera 项目的一些初步工作还表明，非常高分辨率的气候运行如何改善上游热通量特征、风暴路径的倾斜以及下游风暴路径的统计特性。在当前的博士项目中，我们将研究西大西洋地区海洋和大气之间的高分辨率耦合对大气经向热通量的影响以及随之而来的对风暴路径的影响。对于这项工作，我们将配合英国环境预测计划的第二阶段，该计划旨在为英国开发高分辨率（1公里或更小）耦合预测模型。该计划的一部分是评估这种高分辨率耦合模型可以解决的新科学问题。特别是，海洋和大气之间的热交换发生在相对较小的规模上，很难解决，但预计它将有助于气旋产生的整体热传输，并暗示风暴路径的预期下游结构。该项目旨在利用高分辨率运行的数据在广泛的尺度上建立海洋和大气之间的联系，并建立与下游风暴路径结构的联系。我们将检查统计特性以及特定时间段（案例研究）。目的是耦合的高分辨率建模是否可以改进我们对这些大气热通量的预测，以及希望的改进是否会导致英国风暴预报的相应改进。该项目还将利用新开发的技术来绘制风暴路径发展的相空间，其中可以以动态一致的方式跟踪上游斜压增长率和风暴路径活动之间的相互作用。