Theory 57/Mountain & Alpine/Alpine phenology
Phenology Is Gated by Snowmelt
The claim
Alpine plant phenology is gated by snowmelt date rather than by temperature, so a warm spring under deep snow produces no advance.
01Mechanism
Growth cannot begin until the plant is exposed; the snowpack sets the start independent of air temperature.
02Prediction
Phenology should track snowmelt date.
03Refutation
Phenology tracking spring temperature would remove snow.