Radiance simulator Updates


Version 1.1 Release Note (selected changes)

Radiance simulator v1.1 was released in October 2015. The following lists contain details of the changes made between versions 1.0 and 1.1.


  • RTTOV coefficient files in HDF5 format can now be used instead of the ASCII ‘.dat’ files.
    This is essential for simulating very new instruments as coefficient files will be generated only in HDF5 format in future.
  • Met Office Fieldsfiles containing 32-bit values (standard files contain 64-bit values) can now be used.
    This can help save disk space. There is no discernible difference in accuracy when using these files.
  • Simulations involving very large numbers of profiles and channels are automatically split into batches to reduce the memory overhead, avoiding the situation on some systems whereby the virtual memory limit was exceeded for heavily loaded runs.
  • netCDF error handling has been improved so that all errors originating from writing to netCDF files are reported explicitly. This is mainly of use in testing and should not affect users in most cases.
  • Interpolation of other input fields added (surface height and trace gas concentrations but note that trace gases are not used in simulations).
  • Option to change default zenith angle for model grid runs.

Bug Fixes:

  • Fixed assignment of half-level pressures in RTTOV profiles for models where the number of half-levels is greater than the number of levels.
  • This caused runtime failures and therefore does not affect the results of completed runs.
  • Fixed output of half-level pressures (applies only when write_profiles option is switched on).
    This was disabled in the previous version.
  • Fixed incorrect netCDF storage data type for some floating point fields.
    Fields produced with version 1.0 can still be used however.
  • Fixed problem with uninitialised pointers causing runs from Met Office Fieldsfiles to fail on some systems. This does not affect results of completed runs.

  • Fixed problem where the number of half-level pressure values was not initialised correctly before pressure level calculation for Met Office Fieldsfiles. This caused runtime failures on some systems but did not affect results of completed runs.
  • Changed fieldsfile input to read and discard unwanted fields instead of using file positioning, in order
    to avoid a compiler bug with the pgfortran compiler whereby the file was positioned incorrectly on some READ statements.
  • Fixed assignment of cloud fields in RTTOV profiles for IR scattering simulations when the input profiles have a negative z-axis.