Chapter 9 (Updated): Models for atmospheric propagation delays
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- 10 June 2013:
- 15 January 2013:
- Introduce the model Global Pressure and Temperature 2 in sections 9.2 "Tropospheric model for radio techniques" and 9.3 "Sources for meteorological data". 
- In the section 9.4 "Ionospheric models for radio techniques", correct some numerical values in a number of equations for using exact CODATA (2010) values of fundamental constants. Changes are not significant with respect to the uncertainties of the quantities.
- 10 August 2012:
Changes with respect to previous version of the chapter:
- In the section 9.2 "Tropospheric model for radio techniques", correct a typo in the Chen and Herring gradient mapping function.
- In the section 9.4.1 "Ionospheric delay dependence on radio signals including higher order terms", the part "Ray bending effects on geometric path excess and ionospheric delay" has been updated.
- 26 March 2012:
- 25 November 2011:
- FCUL_A.F - Function to compute the global total FCULa mapping function, dependent on latitude, height, and surface temperature. 
- FCUL_B.F - Function to compute the global total FCULb mapping function, dependent on latitude, height and day of year. 
- FCUL_ZD_HPA.F - Subroutine to compute the Mendes-Pavlis zenith total delay, for optical wavelengths, valid for infrared to ultraviolet.
- GMF.F - Subroutine to compute the Global Mapping Functions, GMF. 
- VMF1.F - Subroutine to compute the Vienna Mapping Functions 1, VMF1, to be used with "a" coefficients computed for a given site. (Updated March 26, 2012)
- VMF1_HT.F - Subroutine to compute the Vienna Mapping Functions 1, VMF1, with height corrections, to be used with "a" coefficients computed for a grid.  (Updated March 26, 2012)
- GPT.F - Subroutine to compute the Global Pressure and Temperature, based on spherical harmonics up to degree and order 9. 
- GPT2.F - Subroutine to compute the Global Pressure and Temperature 2 model, and the "a" coefficients for VMF1_HT.F, based on the file gpt2_5.grd.  (Updated June 10, 2013)
- APG.F - Subroutine to compute the asymmetric delay d in meter caused by gradients. The north and east gradients are also provided, based on spherical harmonics up to degree and order 9.
- gpt2_5.grd - Global 5° x 5° grid of mean values and annual and semiannual variations of the quantities for the model GPT2. 
- Figures associated with this chapter.
- Additional Supporting Material is available for this chapter.
 Noted by Changyong He
 Noted by D. Ferguson
 Provided by J. Boehm
 Noted by R. Langley
 Provided by E. Petrie and M. Hernandez Pajares
 Noted by J. McCarthy
 Noted by Ian Martin
 Provided by V. Mendes