"Net heat flux" refers to the overall transfer of heat energy between two objects or regions. It describes the balance between the amount of heat transferred into or out of a system. Full definition
Results are shown for various models in Figure 9.20 It is evident that the models with high effective climate sensitivity also tend to have a large net heat flux into the ocean. (ipcc.ch)
The estimate of increase in global ocean heat content for 1971 — 2010 quantified in Box 3.1 corresponds to an increase in mean net heat flux from the atmosphere to the ocean of 0.55 W m — 2. (skepticalscience.com)
The warming of the world ocean is associated with an increase in global surface air temperature, downward longwave radiation, and therefore net heat flux. (realclimate.org)