Theory 54/Earth & climate/Drought
Drought Onset Is Demand Against Supply
The claim
Drought begins when the ratio of evapotranspiration demand to precipitation supply exceeds one, so a normal dry season becomes a drought only when demand is high.
01Mechanism
Soil water declines when loss outpaces gain.
02Prediction
Onset should track the ratio.
03Refutation
Onset tracking rainfall deficit would remove demand.