Since the major factor in absoebing transfering (to the atmosphere) heat north and south is the ocean....what is happening there is a major factor. The ocean is vast and deep(up to 5 miles deep), with many layers and currents. So, one would want to know what is happening in the deep ocean....not what satellites tell us is happening on the surface, that can be vastly different from below. Looking at one chart may tell us the current weather, but is (selectively) only one factor to be considered.