Surface heating
How much of the sunshine ends up heating the air.
Surface heating shows how much warmth the ground passes to the air above it, in W/m². That warmth is what starts thermals.
How to read it
Section titled “How to read it”More heating means more energy for thermals. It follows the sun through the day, peaks around midday and drops in the afternoon.
What goes into it
Section titled “What goes into it”Not all sunshine becomes heat in the air. Part is reflected, part goes into the ground, and part is used to evaporate water. Dry ground, bare fields and sunny slopes heat the air best; wet ground, forests and shaded slopes less. Cloud cuts the sunshine before it arrives. See Thermals.