Change search
ReferencesLink to record
Permanent link

Direct link
Extinction of the northern oceanic deep convection in an ensemble of climate model simulations of the 20th and 21st centuries
Stockholm University, Faculty of Science, Department of Meteorology .ORCID iD: 0000-0001-8745-7510
2016 (English)In: Climate Dynamics, ISSN 0930-7575, E-ISSN 1432-0894, Vol. 46, no 9, 2863-2882 p.Article in journal (Refereed) Published
Abstract [en]

We study the variability and the evolution of oceanic deep convection in the northern North Atlantic and the Nordic Seas from 1850 to 2100 using an ensemble of 12 climate model simulations with EC-Earth. During the historical period, the model shows a realistic localization of the main sites of deep convection, with the Labrador Sea accounting for most of the deep convective mixing in the northern hemisphere. Labrador convection is partly driven by the NAO (correlation of 0.6) and controls part of the variability of the AMOC at the decadal time scale (correlation of 0.6 when convection leads by 3-4 years). Deep convective activity in the Labrador Sea starts to decline and to become shallower in the beginning of the twentieth century.  The decline is primarily caused by a decrease of the sensible heat loss to the atmosphere in winter resulting from increasingly warm atmospheric conditions. It occurs stepwise and is mainly the consequence of two severe drops in deep convective activity during the 1920s and the 1990s.  These two events can both be linked to the low-frequency variability of the NAO. A warming of the sub-surface, resulting from reduced convective mixing, combines with an increasing influx of freshwater from the Nordic Seas to rapidly strengthen the surface stratification and prevent any possible resurgence of deep convection in the Labrador Sea after the 2020s. Deep convection in the Greenland Sea starts to decline in the 2020s, until complete extinction in 2100. As a response to the extinction of deep convection in the Labrador and Greenland Seas, the AMOC undergoes a linear decline at a rate of about -0.3 Sv per decade during the twenty-first century.

Place, publisher, year, edition, pages
2016. Vol. 46, no 9, 2863-2882 p.
Keyword [en]
Ocean deep convection, Climate change, Climate variability, Global coupled modeling, Atlantic meridional overturning circulation
National Category
Climate Research Oceanography, Hydrology, Water Resources
Research subject
URN: urn:nbn:se:su:diva-123700DOI: 10.1007/s00382-015-2736-5ISI: 000374970200011OAI: diva2:875975
Available from: 2015-12-02 Created: 2015-12-02 Last updated: 2016-06-07Bibliographically approved

Open Access in DiVA

fulltext(3589 kB)24 downloads
File information
File name FULLTEXT01.pdfFile size 3589 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Brodeau, Laurent
By organisation
Department of Meteorology
In the same journal
Climate Dynamics
Climate ResearchOceanography, Hydrology, Water Resources

Search outside of DiVA

GoogleGoogle Scholar
Total: 24 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 101 hits
ReferencesLink to record
Permanent link

Direct link