1. INSTRUMENT STATUS AND PERFORMANCE Guido Levrini

2. Page 2 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 ASAR F Instrument operability issues solved: o Echo shift -> fine tuning of on board parameters o Historic swath parameters (‘Neustrelitz effect’) o N-2 timing patch o Incorrect Wave mode exit -> solved by MP rules o Wave mode switch down -> patch o AP mode SWST annotations -> patch o Incorrect GMM exit -> hopefully solved this week! F Instrument completely operable: no remaining open problem F No TRM failure since launch (4 TRM’s lost in Tx due to PSU) F Excellent instrument stability (~0.2 dB, better than expected) F Antenna patterns completely characterized (all beams/ all pol *) * All HH, VV, VH beams 5/7 HV beams * All HH, VV, VH beams 5/7 HV beams

3. Page 3 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002

4. Page 4 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 MERIS F Instrument availability: ~ 100% F Calibration technique & mechanism: perfectly working F Spectral calibration: characterization confirmed (± 1 Å) by recent spectral campaigns (begin Nov) F Spectral stability: excellent F Radiometric calibration: very good overall stability. o Slow degradation in the blue (@412 nm) -> now in the order of 2 % F Smile correction fully verified -> under implementation in Level 1b.

5. Page 5 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 AATSR F Nominal operations, 100% instr. availability F Temperatures nominal, Cal S/S OK, Coolers functioning nominally, Blanking Pulses OK F Scan mechanism: small jitter (on occasions) F Spectral calibration: OK F Pointing characterization: OK F Dynamic range (all channels) optimized F Radiometric stability: visible channels affected by water condensation.  Outgassing: water removed each time, it comes back at lower rate -> we gradually - but inefficiently - get rid of the water

6. Page 6 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 RA-2 F Over Ice: excellent tracking capabilities F Over Ocean: excellent range noise performance (1.8 cm) F On board parameters optimized: no change since Cal Review F S band accumulation anomaly cured by operational work-around F Datation correction implemented in Level 1b F Absolute Sigma zero calibration (1 st time ever) -> the computed bias is: F Range Absolute Calibration o all data collected o analysis to be finalized (to reduce error bars)

7. Page 7 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 DORIS / LRR / MWR F DORIS Orbit radial accuracy (rms) o Navigator: < 30 cm o Preliminary (2d): < 5 cm o Precise (20d): < 3 cm F LRR: good laser coverage F MWR o 23.8 GHz channel perfectly stable o Suspected slow drift of the 36.5 GHz channel: under investigation

8. Page 8 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 MIPAS F Good NESR performance F Detector non linearity in spec (lower end of dynamic range under optimization) F Radiometric stability: in spec, but affected by ice formation After warm-up, the water builds up slower -> periodic decontamination F In-flight ILS within budget L2 more sensitive than expected -> scheme under improvement F Spectral calibration: OK (including refined NL component in L2) F Pointing: OK. Update on 13 Nov (~25 mdeg in pitch). LOS OK F FOV characterization: OK (using the planet Mercury). F Cooler Anomaly (6-22 Aug, 1-11 Oct). No H/W problem. VCS sensitive to environmental conditions -> Use coarse balancing only.

9. Page 9 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 GOMOS F Good instrument operability F Excellent tracking capabilities (down to 3 km!) F Radiometric stability: excellent F Spectral calibration: OK (± 1/30 pixel) F Spectral stability: excellent F No ghosts on the CCD F CCD sensitive to proton radiation (-> hot pixels and RTS): o operating temperature decreased (+10 -> -4 C, minimum achievable) o dark charge calibration approach changed (every orbit now) o ground processing under update F Independent CCD Expert Investigation Board set-up

10. Page 10 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 SCIAMACHY F All mechanisms working F ‘Flash’ Ice decontamination (during ‘Leonids’) worked. F Dark current stability: excellent in ch.1-6, affected by ice in ch.7-8 F Straylight: Ok in nadir for ch.1-6. Ch.7-8 under investigation F Etalon correction: OK. F PPG: OK for ch. 1-6, under investigation for ch. 7-8. F Spectral calibration: excellent stability F Sun mean reference: recently determined offset under investigation (does not affect DOAS) F Polarization: Nadir is OK, Limb just starting.

11. Page 11 ENVISAT Validation Workshop - ESRIN - 9–13 December 2002 CALENDAR OF MAIN PROCESSOR UPGRADES AATSR21 June4 JulyOn-going ASAR31 May13 Sept12 Novthis week ? MERIS8 April21 June14 AugustOn-going RA-2/MWR21 April5 July18 Nov GOMOS21 June7 AugustOn-going MIPAS18 April30 MayOn going SCIAMACHY30 May5 Septthis week ? N. B. = Updates of Aux Data files to be added