IRSPP

Infrared Sounder Pre-processor (IRSPP)

Current version: v1.3, October 2024

IRSPP is a software package to process hyperspectral sounder data from the Infra Red Sounder (IRS) instrument on the MTG-S1 and MTG-S2 satellites (first launch in 2025).

The main changes in IRSPP v1.3 are (i) to support the IRS test data released by EUMETSAT in July 2024, (ii) to remove obsolete HT-FRTC functionality (which is no longer supported in RTTOV) and substitute equivalent functionality for PC-RTTOV, (iii) to update the output BUFR sequence following user feedback. For more details, please see the Release Note, User Guide and the new test cases (links below).

The near-real-time dissemination stream for IRS will be in the form of netCDF-4 files containing Principal Component (PC) compressed spectra. The IRSPP package will ingest these files and convert to reconstructed radiances using sets of eigenvectors that accompany the spectra. Options will exist for choosing the channel selection, for apodising the spectra, for creating BUFR output and for conversion to alternative PC basis functions. For users who wish to use full-spectral-resolution IRS data to generate their own eigenvectors, the relevant functionality in the IASI PCA deliverable has been transferred to the new package.

The first releases of IRSPP (v1.x) are to familiarise users with the package. They support test data published by EUMETSAT. It is anticipated that further updates will be issued between now and the launch of MTG-S1, with a new main release (v2) being made available after launch. If you have feedback on IRSPP, or would like to discuss with the developers, please contact the NWP SAF helpdesk.

Documentation

IRSPP v1.3 Release Note (28 October 2024)
IRSPP User Manual (28 October 2024)

Superseded documentation

IRSPP v1.0 Release Note (8 March 2022)
IRSPP v1.1 Release Note (13 October 2022)
IRSPP v1.2 Release Note (02 February 2023)

Reference documentation for current release (IRSPP v1)

IRSPP Product Specification (Apr 2018)
IRSPP Top Level Design (Jan 2022)

Reference documentation for next main release (IRSPP v2)

IRSPP v2 Product Specification (July 2024)
IRSPP v2 Top Level Design (July 2024)

Test cases

IRSPP test cases

Bug reports

  • IRSPP v1.2: In libirs/irs_read_irsattr_hdf5.f90, users are advised to comment out line 48 containing “call h5tset_cset_f”. This can cause a crash with some versions of the hdf5 library, when IRS attributes are ASCII, not UTF8. Date of report: 21/08/2023. Fixed in v1.3.