Responses of Atmospheric and Oceanic Heat Transports to Climate Forcing: Compensation versus Collaboration

We present a theoretical study on the responses of atmosphere (AHT) and ocean (OHT) meridional heat transports to climate forcing in a coupled energy balance model. We show that, in general, a surface heat flux forces opposite AHT and OHT responses in the so called Compensation response, while a net heat flux into the coupled system forces AHT and OHT of the same direction in the so called Collaboration response. The relevance of our theory to the response of heat transports to global warming and previous CGCM experiments are also discussed. Our theoretical result provides a guideline for understanding of the response of heat transports and the associated climate changes.