29-03-2010: The atmospheric response to a THC collapse

The theory of the tropical Hadley Circulation is extended to describe the response to a collapse of the thermohaline circulation (THC) in the ocean. Drijfhout (2010) contains relations that predict the shift of the Intertropical Convergence Zone, changes in the strength of the Hadley Circulation, changes in its poleward boundary and the latitude of the Subtropical jets. The theory is compared to the response in a coupled climate model. It is argued that a THC collapse and changes in the tropical atmosphere act in concert to explain abrupt climate change.