1. MTSAT-1R/-2 vs. IASI/AIRS IR GSICS Correction towards pre-operational phase
Masaya Takahashi
Meteorological Satellite Center,
Japan Meteorological Agency

2. Overview and Purpose Overview Purpose of this presentation
MTSAT-1R/-2 vs. IASI/AIRS IR GSICS Correction
Demonstration phase since July 2010
Requirements for pre-operational phase
Uncertainty evaluation incl. documentation: analysis is almost finished
Product review by 1 more reviewer: not yet
ATBD for pre-operational phase and User’s guide: not yet
GSCIS Correction (netCDF) on the THREDDS server: has been done
Purpose of this presentation
To report the uncertainty evaluation
To show the load map towards pre-operational phase
To discuss some ambiguous requirements for pre-operational product

3. Uncertainty evaluation of the MTSAT-2 vs. IASI/AIRS GSICS Correction
GWG_13.10: JMA to complete Uncertainty analysis for MTSAT-IASI products by analyzing random errors contribution from spatial and temporal variability at least and combine these with the currently analysed systematic uncertainty. That will be sufficient for promotion to pre-operational status.

4. Analysis method (Hewison 2013)
Total uncertainty:
Systematic uncertainty Random uncertainty
(zi: random number)
g(L): GSICS Correction, based on the regression of monitored/reference collocated radiances
Monte-Carlo approach
Temporal mismatch
Longitudinal mismatch
Latitudinal mismatch
Geometric mismatch
Spectral mismatch (*)
Spectral Calibrations
Temporal Variability
Longitudinal Variability
Latitudinal Variability
Geometric Variability
Spectral Variability
Radiometric Noise (GEO)
Radiometric Noise (LEO)
* Great thanks to Dorothee for providing simulated IASI spectra up to 3030 cm-1
Hewison, T.J., 2013: An Evaluation of the Uncertainty of the GSICS SEVIRI-IASI Intercalibration Products, IEEE TGRS, 51(3),

5. Systematic uncertainty of IASI-A GSICS correction
Consistent results w/ SEVIRI
Spectral mismatch is dominant for SWIR channel
Temporal/Spatial mismatches are dominant for WV/window channels
Total systematic uncertainty at standard scene line)
MTSAT-2/Imager
0.030K K K K
MSG-2/SEVIRI
0.008K K K K
(Hewison 2013)

6. Random uncertainty of IASI-A GSICS correction
Total random uncertainty at standard scene line)
Consistent trend w/ SEVIRI, but larger uncertainties
Due to the instrument’s accuracy? Need to be investigated further…
MTSAT-2/Imager
0.032K K K K
MSG-2/SEVIRI
0.009K K K K
(Hewison 2013)

7. Uncertainty comparison between IASI/AIRS GSICS Corrections
IASI super channel for MTSAT-2/Imager IR4 (3.8um)
Super channel for GEO imager
Convolution of hyper-spectral sounder’s radiances using spectral gap-filling method (Tahara and Kato, 2009)
Main difference: Spectral coverage
Expected to be found on the systematic uncertainty (GEO spectral mismatch)
AIRS super channels for MTSAT-2/Imager
Missing IASI/AIRS channels
IR4 (3.8um) IR3 (6.8um) IR1 (10.8um) IR2 (12.0um)

8. Systematic uncertainty of AIRS/IASI GSICS Correction
Uncertainty of AIRS GSCIS Corrections
Spectral mismatch is dominant for all the channels
Total systematic uncertainty at standard scene line)
AIRS
0.13K K K K
IASI
0.030K K K K

9. Random uncertainty of AIRS/IASI GSICS Correction
Total random uncertainty at standard scene line)
No significant difference between AIRS/IASI GSICS Correction
AIRS
0.046K K K K
IASI
0.032K K K K

10. Promotion of MTSAT GSCIS Correction to pre-operational phase
Uncertainty evaluation
LEO spectral calibration (IASI/AIRS accuracy): not validated yet
Documentation: not yet
Will be finished by the end of summer 2015
S-NPP/CrIS wouldl also be considered (Dr. Yoshino is working on the implementation)
ATBD and User’s guide
Will be prepared by the end of summer 2015
Product review
Difficult to find an internal reviewer now due to the preparation for Himawari-8/AHI products
Would be great if the GCC introduce a reviewer

11. Discussion
Responsibility for promoting non-operational instruments’ GSCIS Correction to operational phase
Himawari-8 will take over MTSAT-2 in mid-2015
MTSAT-2 will be in the “back-up” operation mode of Himawari-8
MTSAT-1R re-orbit: planned at the end of 2015
Should we promote these products to operational phase even after they will stop the operation? (This could be related to “re-processing” of the GSICS Correction)
Configuration of GEO-LEO-IR
Window period: Should we use the common one?
EUMETSAT/NOAA: 29-day window for RAC, JMA: 30-day
Hour range for the products
EUMETSAT and NOAA: night-time observation for all the channels
JMA: night-time for SWIR (3.8um), day/night time for other channels
Are GEO-LEO-IR GSCIS Correction derived from night-time observation only recognized as the GSICS products?

12. Thanks for your attention