Operation of the wet-pad lowers the transpiration (Fig. 2B and D). The reduced transpiration remains dependent on global radiation, but the relation is weaker than without the wet-pad.
Transpiration when the wet-pad operates is lower in the afternoon than in the morning for the same global radiation. Interruption of wet-pad operation reverts transpiration and its relation to global radiation to the values found in the roof ventilated treatment, indicating that wet-pad operation is the exclusive cause of the change