Figure 5.7 Upper: Zonal averages of heat transfer to the ocean by insolation QSW, and loss by longwave radiation QLW, sensible heat flux QS, and latent heat flux QL, calculated by DaSilva, Young, and Levitus (1995) using the COADS data set. Lower: Net heat flux through the sea surface calculated from the data above (solid line) and net heat flux constrained to give heat and fresh-water transports by the ocean that match independent calculations of these trasports. The area under the lower curves ought to be zero, but it is 16W/m2 for the unconstrained case and -3W/m2 for the constrained case.