1. IR hyperspectral comparisons
Presented by Denis Jouglet
GSICS annual meeting 2016, JAXA, Tsukuba, Japan

2. Discussion about IASI-A end of life operations
Discussion about IASI non-linearity tables update
Future inter-comparison to TANSO-FTS/2

3. IASI-A end of life operations
After the IASI-C cal/val (mid 2019), IASI-A should decommissioned
 Opportunity to propose specific end of life operations!
For calibration and inter-calibration, the following ideas have been proposed and are under assessment (joint work by CNES & EUMETSAT):
IASI-A to keep the same local time at ascending node but with a slightly lower altitude
Would provide numerous real Simultaneous Nadir Observations with IASI-B and IASI-C, even over a short period of time
Requires resources (manoeuvers)
IASI-A, B and C to make simultaneous lunar observations, without any satellite rotation (Cold Space 2 Target)
Would provide TIR hyperspectral spectra of the Moon
Would assess the use of lunar inter-calibration in the TIR
Any comment from GSICS? Any suggestion?
If interested, support from GSICS could help to motivate the request

4. IASI non-linearity tables update
IASI inter-comparisons show a small bias in IASI B1
A residual default of the analog non-linearity correction in B1 of at least one IASI is a possible explanation
Non-linearity is corrected in the IASI interferograms by on board processing, with pre-computed correction tables (cannot be corrected by a simple scaling).
Studies performed at CNES to try to diagnose the impact of non-linearity residuals
The conclusion is likely to update the tables
There is no possibility to re-process the former data (interferograms are not downloaded on ground)
 Changing the table makes a small gap in the calibration
Question for GSICS: Which one is better?
Implement this correction on-board : improves absolute calibration but breaks the radiometric stability
Stay with the current tuning
Provide an estimated a posteriori correction (with error bars)
Illustration of impact : Mean radiometric error between without and with operational non-linearity correction

5. Future inter-comparison to TANSO-FTS 2
GOSAT-2 is planned for the end 2017
TANSO-FTS / GOSAT-2 has a broad TIR band
Will fly at the same period as IASI-A, IASI-B, IASI-C, CrIS, AIRS?, others?
The local time at ascending node provides SNOs with all other missions
Does NIES or JAXA plan an inter-comparison at level 1?
Does GSICS plan such inter-comparison?
From Matsunaga et al., June 2015, IWGGMS-11