A model intercomparison of changes in the Atlantic thermohaline circulation in response to increasing atmospheric CO 2 concentration

As part of the Coupled Model Intercomparison Project, integrations with a common design have been undertaken with eleven different climate models to compare the response of the Atlantic thermohaline circulation (THC) to time‐dependent climate change caused by increasing atmospheric CO 2 concentration. Over 140 years, during which the CO 2 concentration quadruples, the circulation strength declines gradually in all models, by between 10 and 50%. No model shows a rapid or complete collapse, despite the fairly rapid increase and high final concentration of CO 2 . The models having the strongest overturning in the control climate tend to show the largest THC reductions. In all models, the THC weakening is caused…