Lake Erie contains about 4.8 x 10^17 grams of fresh water. Assume that the lake has frozen solid and that the ice starts off at -3 C. How much energy would the lake need to absorb from the Sun to cause it to evaporate completely?
2 answers
Each gram of water will require 1.5 + 80 + 100 + 540 = 721.4 calories to heat up, melt and evaporate. That equals 3109 joules. Multiply that by the mass of water in the lake.
Make that 721.5 calories. (typing error)