Function VapPress(S, T) 'Calculate the vapor pressure of water for seawater. 'Equation is from Weiss and Price (1980) Mar Chem 8: 347-359. 'INPUT: Salinity (S) in g/kg or IPSS-78. ' Temperature (T) in degrees C. 'Output: Vapor pressure of water in atm. T = T + 273.15 VapPress = exp(24.4543 - (6745.09/T) - 4.8489 * Log(T/100) - 0.000544*S) End Function