"The NAO is affected by processes internal to the troposphere, and by “external” effects from the stratosphere above. In today’s climate, it is not understood what fraction of NAO variability is attributable to the stratosphere. This project is focused on understanding future climate—how the NAO will change, how jets and storm tracks will shift. It is an important challenge, because without a fundamental understanding of the physical processes involved, and without models that realistically simulate these changes over time, we are left with low confidence in climate projections—especially how climate will change over the large European sector. Thus, this topic is highly relevant to society.Following a 25-year highly successful career at a private research institute in the United States, I moved in 2012 to the UK to join the faculty of the University of Exeter. This CIG project is designed to help me to integrate into both the EU and the University system. To me, integration into the EU means developing a successful career as an educator and researcher, mentoring graduate students and post-docs, whilst maintaining an adequate stream of external funding to support these activities. This project primarily supports a graduate student, and is a key component of my integration into the EU. This integration is particularly challenging because it is not possible to take US-based funding to any institution out- side the US.This is a current problem with an urgent need for a solution. This problem is highly relevant to society, and the results have practical benefits. This proposal pushes the frontiers of research knowledge in two closely intertwined areas: 1) vertical coupling of the stratosphere to the troposphere (primarily the NAO), and 2) how state-of-the-art climate models do not do an adequate job of simulating variability of the jets and storm tracks (closely related to the NAO)—which calls into question the climate projections made using these models."