Variability and Predictability of Near-Surface Winds

近地表风的变化和可预测性

基本信息

批准号：
RGPIN-2014-06509
负责人：
Monahan, Adam
金额：
$ 3.79万
依托单位：
University of Victoria
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2015
资助国家：
加拿大
起止时间：
2015-01-01 至 2016-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=589056
关键词：
Variability Predictability Near Surface Winds

项目摘要

The most familiar feature of the motion of air near the Earth's surface is its variability. While variations on daily or seasonal timescales are regular, most near-surface wind variability is irregular - from short-timescale turbulent fluctuations to longer timescale variations driven by large-scale weather and climate processes. Understanding the variability of near-surface winds is important because they are a leading-order control on exchanges of mass, energy and momentum between the atmosphere and the land or ocean surfaces; wind energy is a significant renewable energy source; and wind extremes can be damaging to the natural and built environments. Although the underlying physics is the same, wind behaves differently over land than over water. As well, different physical processes determine its variability on different timescales. A central goal of my research is to build a fundamental understanding of these controls on variability and the consequent implications for predictability. The following projects are proposed towards this end. My research group and I will: 1. use modern techniques from applied mathematics and statistics to investigate transitions between near-surface wind "regimes" which we have shown are associated with unusually strong nighttime winds. 2. determine how changes in sea surface temperature modulate the mean, variability, and extremes of near-surface wind over the ocean. 3. study new approaches to the problem of fitting wind observations to our wind models, to improve their quantitative utility. 4. examine the physical reasons for the observed difference in the statistical predictability of winds coming from different directions. 5. quantify how the predictability of wind speed changes on different timescales. 6. assess the physical controls on the fact that the "memory" of wind variability falls off at different rates for winds from different directions. This proposed research builds in new and important directions on the foundational research we have carried out in recent years. The new research will result in important advances in our fundamental physical and mathematical understanding of the variability and extremes of surface winds, with implications for their simulation in comprehensive climate models and for the assessment and prediction of the wind energy resource.

地球表面附近空气运动最常见的特征是其变化性。虽然每日或季节性时间尺度的变化是有规律的，但大多数近地表风的变化是不规则的——从短时间尺度的湍流波动到由大规模天气和气候过程驱动的较长时间尺度的变化。了解近地表风的变化非常重要，因为它们是大气与陆地或海洋表面之间质量、能量和动量交换的主序控制；风能是重要的可再生能源；极端风力可能会损害自然和建筑环境。尽管基本物理原理相同，但风在陆地上的表现与在水上不同。同样，不同的物理过程决定了其在不同时间尺度上的变化。我研究的一个中心目标是建立对这些变异性控制及其对可预测性的后续影响的基本理解。为此，建议实施以下项目。我和我的研究小组将： 1. 使用应用数学和统计学的现代技术来研究近地表风“状态”之间的转变，我们已经证明这些风“状态”与异常强的夜间风有关。 2. 确定海面温度的变化如何调节海洋近地表风的平均值、变异性和极端值。 3. 研究将风观测数据与风模型拟合的新方法，以提高其定量效用。 4. 检查观察到的不同方向风的统计可预测性差异的物理原因。 5. 量化风速的可预测性在不同时间尺度上的变化。 6. 评估对来自不同方向的风的风变率的“记忆”以不同速率衰减这一事实的物理控制。这项拟议的研究建立在我们近年来开展的基础研究的新的重要方向上。这项新研究将在我们对地面风的变化性和极端情况的基本物理和数学理解方面取得重要进展，这对于综合气候模型中的模拟以及风能资源的评估和预测具有重要意义。