Persistence of seasonal Climate Anomalies: Drivers, Mechanisms and Process-based Diagnostics

随着改善季节性预报的最终目标，我们的目标是推进对影响欧洲季节性天气的三个关键边界条件的机械理解：北大西洋上层海洋热含量，北极海冰和平流层。夏季天气和气候将是主要焦点。该项目将使用最先进的耦合气候模式实验，理想化的动力框架和先进的统计技术的混合物。这项工作将通过五个相互作用的工作包（WP）来实现：我们的总体目标是提高英国气象局全球季节预报系统（GloSea 5）的技能。要做到这一点，必须对系统进行批评，并找出不足之处。每个WP都以不同的方式满足这些需求。海洋驱动因素-可能影响夏季风暴路径位置的上层海洋热含量（以及相关的阻塞和北大西洋涛动）; WP 2。海冰驱动因素-冬季/春季北极海冰范围和厚度可能导致欧洲夏季降雨量的变化; WP 3。平流层驱动因素-平流层变化对对流层的影响（包括QBO）; WP 4。理想化动力学模型的层次结构，以深入了解驱动因素如何导致持续性和季节性异常; WP 5。次季节时空过程的统计建模，以便更好地量化和了解驱动因素对变异模式的作用。

With the ultimate goal of improving seasonal forecasts, we aim to advance mechanistic understanding of three key boundary conditions that influence European seasonal weather: North Atlantic upper-ocean heat content, Arctic sea-ice and the stratosphere. Summer weather and climate will be principal focus. The project will use a mixture of state-of-the-art coupled climate model experiments, idealised dynamical frameworks and advanced statistical techniques.The work will be achieved by five interacting WorkPackages (WP): Our overall goal is to improve the skill of the Met Office Global Seasonal forecast System (GloSea5). To do this, the system must be critiqued, and deficiencies must be identified. Each WP addresses these needs in various ways.WP1. Oceanic drivers - Upper-ocean heat content which may affect the position of the storm track in summer (and related blocking and NAO);WP2. Sea ice drivers - Arctic sea-ice extent and thickness in winter/spring which may cause variations is summer rainfall in Europe;WP3. Stratospheric drivers - Influence on the troposphere from stratospheric variations (including the QBO);WP4. Hierarchy of idealised dynamical models to gain deep mechanistic understanding of how drivers can lead to persistence and seasonal anomalies;WP5. Statistical modelling of sub-seasonal space-time processes for better quantification and understanding of the role of drivers on modes of variability.