Book 30, Question 40
Why is a lake cold in spring but warm in the fall?
Water takes a lot of energy to heat up, and it stays warm a long time.
After winter, a lake is still cold, so beaches feel chilly even on sunny days in May. By late summer, the lake has soaked up so much warmth that it stays comfy into September, even when the air cools. The land heats and cools much faster.