Sting jets in severe Northern European windstorms

1999年12月，三场极端强烈的风暴（包括洛塔尔和马丁）袭击了欧洲，造成130多人死亡，经济损失总额约为130亿欧元。这些风暴都伴随着超过78节的狂风。重大财产损失发生，大面积森林被毁，交通和电力中断持续了数天。与马丁有关的风暴潮导致大西洋沿岸几个地区发生洪水。虽然这些风暴的更大规模方面通常可以用合理的技术进行预测，但主要风灾的发生、位置和局部地区的严重程度却无法预测。在风暴生命周期的大部分时间里，在风暴的温暖区发现了一个广泛的中等强风区域。一些，但不是所有的风暴都有第二个局部的强风区域，尤其是强风，可能持续时间很短（几个小时），但破坏力特别强。这被称为“刺状喷流”，它的结构直到最近才通过对强风暴的数值模拟来确定。“刺状喷气机”一词引起了媒体的注意（如《每日电讯报》、英国广播公司第4台、2003年皇家学会夏季科学展览）。然而，值得注意的是，目前这项研究仅基于对单一风暴的详细分析，我们还不知道表现出刺状喷流的风暴的特征。在用于预测未来气候情景下风暴变化的气候模式中也没有Sting喷流。我们建议确定导致刺状急流的机制，开发可用于预测给定风暴中刺状急流的发展和存在的诊断方法，确定这些风暴在当前气候中的气候学，并考虑这些风暴在未来气候情景下可能发生的变化。这将通过分析高分辨率的案例研究和理想的数值模型预测来实现。这些严重风暴的社会经济影响意味着，研究结果对有责任减轻和应对这些事件影响的用户（例如，DEFRA、环境署、电力公司等公用事业供应商）具有相关性。

Three extremely strong storms (including those named Lothar and Martin) hit Europe in December 1999 claiming more than 130 lives and causing about 13 billion Euros total economic losses. These storms were each associated with violent gusts exceeding 78 knots. Significant property damage occurred, vast areas of forest were destroyed and transport and power outages lasted for days. The storm surge associated with Martin led to flooding along several parts of the Atlantic coast. While larger-scale aspects of these storms are generally forecast with reasonable skill, the occurrence, location, and severity of the local regions of major wind damage are not. A broad region of moderately strong winds is found in the warm sector of the storm for most of its lifecycle. Some, but not all, storms have a second localised region of strong winds, and especially strong gusts, which may be short lived (a few hours) but especially damaging. This has been termed a 'sting jet' and its structure has only recently been identified by numerical model simulations of an intense storm. The term 'sting jet' has captured media attention (e.g. the Telegraph newspaper, BBC radio 4, 2003 Royal Society Summer Science Exhibition). However, it is remarkable that at present this research is based on detailed analysis of only a single storm and we do not know the characteristics of storms that exhibit sting jets. Sting jets are also not represented in the climate models used to predict changes to storminess under future climate scenarios. We propose to determine the mechanisms that lead to sting jets, develop diagnostics that can be used to predict the development and presence of a sting jet in a given storm, determine the climatology of these storms in the current climate and consider the possible changes to these storms under further climate scenarios. This will be achieved through analysis of high-resolution case study and idealised numerical model forecasts. The socio-economic implications of these severe storms means that the findings will be of relevance to users with the responsibility for mitigation of and response to the impacts of these events (e.g., DEFRA, the Environment Agency, utilities providers such as power companies).