Evaluation of Wet Mapping Functions Used in Modeling Tropospheric Propagation Delay Effect on GPS Measurements

Table 2: Summary table of the main features of wet mapping functions.

Code	Reference	Impute parameters	ε_min˚
SA	Saastamoinen (1987)	*z, T₀, e_o*	*10˚*
HO	Hopfield (1971)	*ε, T₀, e_o*	**
BL	Black (1978)	*ε, T₀, e_o, r*	5˚
CH	Chao (1972)	ε	*10˚*
IF	Ifadis (1986)	*ε, t₀, e_o, P₀*	2˚
HE	Herring (1992)	*ε, t₀, φ, H_o*	3˚
NI	Niell (1993)	*ε, φ*	3˚
MO	Moffett (1973)	ε	2˚
B & E	Black and Eisner (1984)	ε	7˚
UNBabc	Gue J. and Langley R. (2003),	*ε, φ, H₀*	2˚

where: φ is the station latitude, H is the station height, r is the effective radius of the station, T₀ is the temperature at site in K˚, t₀ is the temperature at site in ˚C, e₀ is the partial water vapor pressure in (mb), z is the zenith angle and ε is the elevation angle. ** Means that: not specified or valid for any elevation angle.