Calculate the global average latent heat flux. The average annual rainfall across the entire globe is 1 m. That means 1 m of water must evaporate every year from the surface.
a. Calculate the energy used to evaporate 1 m of water. You want your answer to be in J/m2. Recall that the latent heat of vaporization for water is 2260 kJ/kg, or 2.26x106 J/kg, and the density of water is 1000 kg/m3.
? J/m2
b. Convert this value to W/m2. This the global average latent heat flux. To do the conversion, you have to realize that the value calculated in part (a) is over the course of an entire year. You may use that the fact that there are 3.15x107 seconds in a year, and 1 Watt = 1 J/sec.
? W/m2
c. Compare the value for latent heat flux calculated in (b) with the incoming solar flux at the top of the atmosphere. What percentage of that energy goes into evaporating water?