A modeling study of the impact of meso-scale air sea interactions over the Gulf Stream on weather and climate

本提案中描述的研究旨在评估海洋环流变化对北大西洋和北欧冬季气候状况的影响（这些是冬季大气最频繁存在的国家，例如，北欧有强急流和温暖潮湿天气的国家）。为此，我们将进行第一次对流模拟，模拟墨西哥湾流上的主要气旋形成区域，研究与天气和气候时间尺度相关的物理过程。这种方法是新颖的，因为：(i)所考虑的海洋强迫发生在海洋和大气锋的尺度上（10-100公里），在冬季气候条件的上游。目前在气候或天气预报模型中没有考虑到这种物理现象。（ii）它植根于对北大西洋尺度相互作用的明确研究。为解决这种相互作用而开发的新方法依赖于天气和气候科学家之间真正的跨学科合作。如果在10-100公里尺度上发现海气相互作用对海面温度的敏感性，预计这项研究的重大突破将是打开一个尚未开发的气候和天气可预测性来源。关于这一主题的研究议程也将转向包括对大气锋面上发展的不稳定性及其与海洋的相互作用的准确描述。在项目中进行的研究将对这些相互作用进行可靠的试点研究，并提供一个模型输出数据库，在此基础上可以发展新一代的参数化。该项目还将加强在其他NERC资助的项目中进行的研究，如DIAMET（热带外风暴中尺度结构的非热影响），将其与墨西哥湾流区域的相关性扩大，以及RAPID-WATCH（监测北纬26度的大西洋环流），通过提供将海洋环流变化传达给大气的新途径。

The research described in this proposal aims at assessing the impact of changes in ocean circulation on winter climate regimes over the North Atlantic and Northern Europe (these are the states in which the atmosphere resides most frequently in winter, for example, a state with a strong Jet Stream and warm humid weather over Northern Europe). To do this we will perform the first convection permitting simulations of the dominant cyclone genesis region overlying the Gulf Stream, investigating physical processes relevant to both weather and climate time scales. The approach is novel because:(i) the oceanic forcing considered occurs on the scale of oceanic and atmospheric fronts (10-100km), upstream of the wintertime climate regimes. This physics is not currently taken into account in climate or weather forecast models. (ii) it is rooted in an explicit study of scale interactions over the North Atlantic. The new methodology developed to tackle this interaction relies on a truly interdisciplinary collaboration between weather and climate scientists. The major breakthrough expected from this research, if indeed sensitivity to sea surface temperature via air-sea interactions on the 10-100km scale is found, is that an untapped source of climate and weather predictability will be opened. The research agenda on this topic would also shift towards including an accurate representation of instabilities developing on atmospheric fronts and their interactions with the ocean. The research carried out in the project would provide a solid pilot study of these interactions and a model output database on which a new generation of parameterizations could be developed.The project will also enhance the research carried in other NERC funded programmes such as DIAMET (DIAbatic Influence on Mesoscale structures in ExTra-tropical storms) by extending its relevance to the Gulf Stream region, and RAPID-WATCH (monitoring of the Atlantic ocean circulation at 26N) by providing a new pathway through which changes in ocean circulation can be communicated to the atmosphere.