In Reply Refer To - Water Resources of the United States: U.S. Geological Survey
Attachment Page A4 of A11 where P is the barometric pressure in mm Hg and u is the vapor pressure of water in mm Hg. An empirical relation for the vapor pressure of water in mm Hg was presented in Technical Memorandum 81.11 as: ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ + − u = 235 t...