Spectral response functions

Visible/IR spectral response functions (SRFs) and MW passbands

Spectral response functions for VIS/IR coefficient files

All coefficient files for a particular instrument (e.g. those based on different predictor versions) use the same SRF data.

The channels for each instrument are listed in the coefficient file order. You can confirm the RTTOV channel order by looking at the coefficient file headers or by using the rttov_coef_info.exe tool.

The README_SRF section is copied from the coefficient files at the top of each page linked below. For instruments with both IR-only and VIS/IR coefficient files the README_SRF sections from both coefficient files are copied when they are not identical.

If you have information on updates or corrections to any of the spectral response functions please let us know either on the RTTOV forum or via the NWP SAF Helpdesk.

(A)ATSR

ABI

AHI

ASTER

AVHRR

ECOSTRESS

FCI

  • MTG 1 FCI – SRFs cannot be published due to licence restrictions

GMS IMAGER

GOES IMAGER

GOES SOUNDER

HIRS

IIR

INSAT-3D(R) IMAGER

INSAT-3D(R) SOUNDER

IRAS

IRMSS

LI

  • MTG 1 LI – SRFs cannot be published due to licence restrictions

MBFIRI

MERSI-1

METIMAGE

MI

MODIS

MRIR

MSUMR

MTSAT IMAGER

MVIRI

MVISR

OLCI

OLI

SEVIRI

SGLI

SLSTR

THIR

TIRS

TM

VIIRS

VISSR

VTPR


Pass band data for MW coefficient files

Key for MW pass band filter files:
  Two records for each channel
  Fields in record 1: channel, polarisation, no-of-offsets, bandwidth (MHz)
  Fields in record 2: central frequency (GHz), offset1 (GHz), offset2 (GHz)

  Notes
  (1) Polarisation – this refers to the FASTEM surface emissivity model:
         0: Average of vertical and horizontal polarisation i.e. 0.5(H+V)
         1: Nominal vertical at nadir rotating with view angle QV
         2: Nominal horizontal at nadir rotating with view angle QH
         3: Vertical V
         4: Horizontal H
         5: +45 minus -45 (3rd stokes vector) S3
         6: Left circular – right circular (4th stokes vector) S4

  (2) no-of-offsets
         0: one passband channel
         1: two sideband channel
         2: four sideband channel

  (3) Bandwidth is for each passband

If you have information on updates or corrections to any of the spectral response functions please let us know either on the RTTOV forum or via the NWP SAF Helpdesk.