Atmosphere, international standard, thermodynamic properties

TABLE 2-236 Thermodynamic Properties of the International Standard Atmosphere ... 

IAPWS-95 is now the state of the art and the international standard for representing water s thermodynamic properties at temperatures from its freezing point to 1000°C and at pressures up to 1000 MPa. It also extrapolates in a physically meaningful manner outside this range, including the supercooled liquid water region. The uncertainties in the properties produced by IAPWS-95 are comparable to those of the best available experimental data this is quite accurate in some cases (for example, relative uncertainty of 10 for liquid densities at atmospheric pressure and near-ambient temperatures) and less so where the data are less certain (for example, relative uncertainty of 2 x 10 for most vapor heat... 

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