But the temperature increase could prove disastrous for the lakes’ long-term water levels because it is driving up evaporation rates. NOAA data show that evaporation on Michigan and Huron was above average every year from 2013 dating back to 1999, when the lakes’ record long low-water era began. With little to no protective winter ice cap, chilled air whooshing over relatively warm water leads to more evaporation. The result of this thermal avalanche triggered by just a tiny blip in air temperatures: the surface of the lakes is going poof into the sky.
