Analysis of L1b files with restituted attitude Bianca M. Dinelli E. Papandrea

L1b files with pointing information coming from the satellite restituted attitude have been provided The spectra contained in the L1b files previously delivered are compared with the new ones Examined orbits: –12963 (Reduced Resolution) –10600 (Full Resolution)

12963 (RR 17 limb views per scan) Old: MIP_NL__1PTETB _163350_ _00384_12963_0000.N1 New: MIP_NL__1P_12963-RES_ATT.04822

Tangent points location

Old – New (sweep 8)

Old – New (sweep 9)

Old – New (sweep 10)

Old – New (sweep 11)

Orbit of 10/3/2004 full resolution (0.025cm -1 ) 17 sweep per scan Old: tangent points information as in the L1b file delivered via tape New: tangent points information coming from satellite restituted attitude

L1B files of Orbit Old: MIP_NL__1PPDPA _144033_ _00025_10600_2930.N1 New: MIP_NL__1P_10600-RES_ATT

Comparison of Old and New spectra (Seq: 14 - Limb 6)

Old – New – Band A

GMTR analysis The spectra of the two L1-b files have been analyzed with the GMTR system Pressure, Temperature O 3 and H 2 O VMR have been simultaneously retrieved Retrieval performed at the nominal altitudes of the Occupation Matrix (same in the two analyses) Note that pointing is NOT retrieved (LOS as in L1-b files)

GMTR analysis  -test evolution Old:  -test = New:  - test = BUT: some sweeps in the new file are flagged as corrupted while previously they were fine

Corrupted sweeps in orbit 10600

Old spectrum of Band A – flagged as corrupted in new file

Old spectrum of Band AB – flagged as corrupted in new file

Tangent points location

OLD NEW GMTR retrieval

OLD NEW

GMTR retrieval OLD NEW

GMTR retrieval OLD NEW

GMTR retrieval OLD NEW

GMTR retrieval OLD NEW

GMTR retrieval OLD NEW

GMTR retrieval OLD NEW

Conclusions L1b spectra differences > noise Forward and Reverse sweeps show different behavior New tangent point locations lower than previous ones New algorithm flags corrupted apparently good sweeps New retrieved profiles smoother that before