Model projections of the North Atlantic thermohaline circulation for the 21st century assessed by observations

TitleModel projections of the North Atlantic thermohaline circulation for the 21st century assessed by observations
Publication TypeJournal Article
Year of Publication2005
AuthorsSchmittner, A., M. Latif, and B. Schneider
JournalGeophysical Research Letters
Volume32
Pagination-
Date PublishedDec 14
ISBN Number0094-8276
Accession NumberISI:000234292500003
Keywordsatmosphere, climate, ensemble, global ocean, hydrographic data, ocean circulation, rates, simulations, system, transport
Abstract

Most climate models predict a weakening of the North Atlantic thermohaline circulation for the 21st century when forced by increasing levels of greenhouse gas concentrations. The model spread, however, is rather large, even when the forcing scenario is identical, indicating a large uncertainty in the response to forcing. In order to reduce the model uncertainties a weighting procedure is applied considering the skill of each model in simulating hydrographic properties and observation-based circulation estimates. This procedure yields a "best estimate'' for the evolution of the North Atlantic THC during the 21st century by taking into account a measure of model quality. Using 28 projections from 9 different coupled global climate models of a scenario of future CO2 increase (SRESA1B) performed for the upcoming fourth assessment report of the Intergovernmental Panel on Climate Change, the analysis predicts a gradual weakening of the North Atlantic THC by 25( +/- 25)% until 2100.

URL<Go to ISI>://000234292500003
Alternate JournalGeophys Res LettGeophys Res Lett