Beyond the instrumental period: Are 20th century changes in North Atlantic circulation exceptional?

Date: 
Friday, 13 October, 2017 - 14:00 to 15:00
Location: 
NOC Southampton - Henry Charnock Lecture Theatre (Waterfront Campus).
Speaker: 
David Thornalley (UCL)

Beyond the instrumental period: Are 20th century changes in North Atlantic circulation exceptional?

The circulation of the North Atlantic is a key component of the regional and global climate system. There are concerns about its future stability under future global warming scenarios, however our understanding of its behaviour on (multi-)decadal and longer timescales is limited because of the short duration of instrumental records. 

In this talk I will present new proxy data from a range of very high sedimentation rate marine sediment cores from around the North Atlantic that enable us to extend the instrumental records and place the 20th century circulation of the North Atlantic in a longer term context. Both surface and deep circulation changes will be examined, focussing on changes in the subpolar gyre and Atlantic meridional overturning and their impact on marine ecosystems. Apparent discrepancies between model and proxy results have important implications for the accuracy of future projections. Although there is much work still to do, the 20th century appears to be quite an exceptional time in the history of the North Atlantic.

Seminar category: 
Friday seminars