Professor Helen Johnson, University of Oxford

Friday 28 April 2017 - 16:00 to 17:00
NOC Southampton - Henry Charnock Lecture Theatre (Waterfront Campus).
Professor Helen Johnson, University of Oxford

What sets the timescale on which the Arctic Ocean adjusts to changes in wind forcing or sea-ice cover?

Changes in Arctic Ocean circulation and freshwater content have the potential to significantly influence regional and global climate. This talk will focus on how quickly the Arctic Ocean responds to a change in sea-ice cover or wind forcing at the ocean surface, and the mechanisms determining the response timescale. I will present evidence from a hierarchy of studies recently carried out in Oxford, from a 1.5 layer reduced gravity model, through idealised numerical ocean model simulations, to analysis of a state-of-the-art coupled climate model control run, showing that (a) the Arctic Ocean and its fresh water content respond to changes in surface forcing on timescales of about a decade, and (b) ocean eddies likely determine this timescale.

Seminar category: 
Friday seminars