"Net evaporation" refers to the overall amount of liquid that turns into vapor from a certain area, subtracting the liquid that is being returned or replenished. It indicates the net loss of liquid due to evaporation. Full definition
In some areas of the ocean, generally during the winter season, cooling or net evaporation causes surface water to become dense enough to sink. (britannica.com)
If you just trust in what you do know you can get to a simpler holistic story: That our atmosphere contains ever more greenhouse gases and therefore absorbs more energy, therefore both temperature and net evaporation go up and the general circulation intensifies, with a declining Polar Cell and an expanding and poleward migrating Hadley Cell. (bitsofscience.org)