function L=vapor(t)
% VAPOR calculates heat of evaporation for pure water
% L=VAPOR(t)computes the heat of evaporation for pure water. This can
% be used to compute the fresh water flux from latent heat flux.
%
% INPUT: t - water temperature [C]
%
% OUTPUT: L - heat of evaporation [J/kg]
% Range of validity: 0 <= t <= 100 deg C. Check value: at t=100 deg C,
% L = 2.2566 x 10^6 J/kg. Reference: Landolt-Bornstein, Numerical Data
% and Functional Relationships in Science and Technology. New Series,
% Sundermann, J. (editor), vol. 3, subvol. a, Springer-Verlag, p. 256.
% No formulas are known to be available for the change of the heat of
% evaporation as function of salinity.
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% 1/22/99: version 1.0 (contributed by RO)
% 8/5/99: version 2.0
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a0=2.50039e6;
a1=-2.3683e3;
a2=4.31e-1;
a3=-1.131e-2;
L=a0+a1*t+a2*t.*t+a3*t.*t.*t;