RTTOV v11.3 was released in September 2015 by the NWP SAF. A list of the main new features of RTTOV v11.3 compared to v11.2 is given below.
RTTOV v11.3- Scientific changes
- New options for specifying units of input gas profiles.
- Lambertian surface option now available for IR sensors.
- New PC-RTTOV coefficients which can be used over all surface types.
- Improved treatment of snow in land surface BRDF atlas.
- Land surface IR emissivity atlas has new option to include a correction for zenith angle.
- Updates to the RTTOV GUI including new 1DVar functionality.
- Technical changes
- RTTOV v11.3 reproduces RTTOV v11.2 radiances for identically configured simulations (bug fixes notwithstanding).
- New wrapper code to allow much RTTOV functionality to be called directly from Python or C/C++.
- IR emissivity and BRDF atlases now also available in HDF5 format: simplifies compilation by eliminating the need for the netCDF library.
- Four new allocation subroutines which can be used to allocate any or all input/output arrays and structures for the RTTOV direct, TL, AD and K models simplifying code which calls RTTOV.
- New interactive scripts for compiling RTTOV and downloading coefficient files from the website: intended to simplify installation of RTTOV.
RTTOV v11.2 was released in June 2014 by the NWP SAF. A list of the main new features of RTTOV v11.2 compared to v11.1 is given below.
RTTOV v11.2- Scientific changes
- New interpolation options are available which eliminate the jaggedness observed in temperature Jacobians under certain circumstances.
- New option for profile extrapolation at top of atmosphere based on regression limits.
- New FASTEM-6 option which has improved treatment of azimuthal dependence.
- Updated Baran ice optical property parameterisation for cloudy IR simulations.
- Technical changes
- RTTOV v11.2 reproduces RTTOV v11.1 radiances for identically configured simulations (bug fixes notwithstanding).
- Code rewritten in places to improve readability and maintenance.
- Test suite profile sets are now based on the six US76 standard atmospheres.
- Code has undergone optimisation for scalar architectures, particularly the solar sea surface reflectance calculation, IR scattering code, and PC-RTTOV.
- Coefficient I/O in HDF5 format now allows channel selection.
- RTTOV GUI is supplied with the RTTOV package: this allows users to run the direct and K models and visualise the results.
RTTOV v11.1 was released in May 2013 by the NWP SAF. A brief overview of the main new features of RTTOV v11 is given here.
RTTOV v11.1- Scientific changes
- Coefficients based on a new set of 54 levels.
- Capability to simulate visible/near-IR channels.
- New land surface bi-directional reflectance function (BRDF) atlas.
- Capability to correct for non-local thermodynamic equilibrium effects.
- PC-RTTOV may now be run for clear-sky and cloudy profiles over sea.
- Option to specify scattering parameters explicitly for aerosol and cloudy IR simulations.
- New ice particle parameterisation for cloudy IR simulations.
- Two new aerosol particle types: a new volcanic ash type derived from measurements of the Icelandic eruption in 2010, and an Asian dust type.
- New option to treat the surface as a Lambertian reflector for the reflected down-welling radiance calculation.
- Capability to account for variable cell pressure in SSU sensors.
- Improvements to MW scattering code including capability to supply hydrometeor profiles in units of kg/kg.
- Technical changes
- RTTOV v11 reproduces RTTOV v10 radiances for identically configured simulations.
- Code rewritten in places to improve readability and maintenance.
- Test suite has been extended to allow all aspects of RTTOV to be configured via input files or via the commandline.
- Code has undergone optimisation for scalar architectures, particularly the direct and K models and the IR emissivity atlas.
- Capability to read and write coefficients in HDF5 format.
- Capability to convert mietables to binary format.
To comment or to suggest future enhancements to RTTOV, please use the NWP SAF feedback form.