The uncertainty in the response of the thermohaline circulation to greenhouse forcing due to the use of flux adjustments in coupled ocean-atmosphere models is evaluated. This is done by using a different yet physically justifiable flux adjustment procedure and examining its effect on the thermohaline response to greenhouse forcing in a three dimensional primitive equations coupled ocean atmosphere general circulation model. It is found that while the initial thermohaline circulation weakening is robust, its eventual recovery which is seen in some coupled model simulations may be more sensitive to the details of the flux adjustment procedure and may therefore be less certain. ¿ 2000 American Geophysical Union