Changes in the atmospheric pressure loading service

[Leonid Petrov <Leonid.Petrov@xxxxxxxxxxx>]

Dear users of the atmospheric pressure loading service,

  Several changes were made:

1) The atmospheric pressure loading displacements time seres were recomputed
   anew. Changes:
   a) New Green's functions are used. With the new Green's function 
      displacements are with respect to the center of mass of the total 
      Earth, the solid Earth and the atmosphere. With the old Green's 
      function the displacements were with respect to the center of mass
      of the solid Earth.
   b) A small error in Green's function at the distances close to 180 degrees
      was fixed.

2) Pressure loading software was upgraded and the new version allows to 
   compute displacements in the vicinity of the northern and southern poles.

3) 13 new sites were added to the station list. 

4) The amplitudes and phases of the atmospheric pressure loading 
   displacements at diurnal and semi-diurnal frequencies were recomputed 
   for 622 sites using updated Greens' function for both IB and non-IB 
   hypothesis:

   http://gemini.gsfc.nasa.gov/aplo/vsgd_aplo_s1_s2_ib.hps
   http://gemini.gsfc.nasa.gov/aplo/vsgd_aplo_s1_s2_noib.hps

5) The amplitudes and phases of the atmospheric pressure loading 
   displacements at diurnal and semi-diurnal frequencies were computed 
   at 2.5x2.5 deg and 1.0x1.0 deg grid:
   http://gemini.gsfc.nasa.gov/aplo/aplo_grid_1.0x1.0_deg_s1_s2_ib.nc
   http://gemini.gsfc.nasa.gov/aplo/aplo_grid_2.5x2.5_deg_s1_s2_ib.nc
   http://gemini.gsfc.nasa.gov/aplo/aplo_grid_1.0x1.0_deg_s1_s2_noib.nc
   http://gemini.gsfc.nasa.gov/aplo/aplo_grid_2.5x2.5_deg_s1_s2_noib.nc


6) There were subtle changes in EPHEDISP format:
   the new format version has wider fields in the P-record -- this allows
   for a file to have displacements for more than 9999 stations and
   it has a new A-record which specifies the radius of validity of 
   the displacements.

7) The was a subtle change in HARPOS format:
   the new format version supports a new A-record which specifies the 
   radius of validity of the displacements. Solve users: upgrade Calc/Solve
   to 2005.04.04 are newer version.

8) The was a subtle change in BINDISP_SUMMARY file
   the new format version supports a new A-record which specifies the 
   radius of validity of the displacements. Solve users: upgrade Calc/Solve
   to 2005.04.04 are newer version.

9) The new pressure loading series are available at 
   http://lacerta.gsfc.nasa.gov/aplo_cm_eph/
   http://lacerta.gsfc.nasa.gov/aplo_cm_bds/

   On 2005.07.11 the old time series will be discontinued and the new time
   series will replace the current ones.

Sincerely,
Leonid Petrov
08-JUL-2005 13:33:03