چکیده (انگلیسی):

The free convections of the fluids water and air over the globe lead to evaporation of water and generation of winds, respectively. Heinrich Hertz and M King Hubbert both assign 40000∙1012W solar power for evaporation of water and subsequent annual rainfall of around one meter over the globe. However, Hertz has mentioned two estimates 400∙1012W and 4000∙1012W in his handwritten lecture notes of 1885 for the wind power. This ambiguity is resolved in present paper showing wind power is of the order 400∙1012W on the basis of his statement that winds should be of the same order of magnitude as that involved in rainfall. This estimate for wind power also matches with the value 370∙1012W assigned by M King Hubbert. Craig F Bohren’s observation that heat transfer coefficient for water is 120 times larger than air is shown to be equal to the ratio of solar power going into evaporation and wind channels. Both Hertz’s and Hubbert’s estimates for evaporation and wind channels further show that solar power for evaporation is two order magnitudes more than solar power generating the winds.