Envisat Validation Workshop Atmospheric Chemistry Validation Team Ground-Based Measurements and Campaign Database Subgroup Comparisons with GOMOS air-density and Temperature Profiles Stéphane Marchand, Page 1 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002

Validation Team Projects involved :instruments :validateproduct:  AOID 153 S. PalToronto Lidar T ( 43.66°N, 79.4°W )  AOID 222 K. H. FrickeEsrange Lidar T, HRTP, density ( 67.9°N, 20.1°E )  AOID 300 D. De MuerUccle radio-soundingsT ( 50.8°N, 4.35°E )  AOID 360 P. KeckhutOHP Lidar HRTP ( 43.94°N, 5.71°E )  AOID 9100 F. CongedutiRome lidarT ( 41.83°N, 12.65°E ) Level 2 GOMOS : GOM_NL__2P* Page 2 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002

Page 3 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 Intercomparison of air-density Profile AO Dist. : 184 km Orb star ID : 155 Mv : 2.9 T : 6600 K.

Page 3 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 Intercomparison of air-density Profile AO Orb. 2091/2092 star ID : 18 Mv : T : 9700 K.

Page 3 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 Intercomparison of air-density Profile AO Orb star ID : 84 Mv : T : 4500 K.

Temperature Temperature = 2 products  (low resolution) Temperature : contribution of O 2 band +rayleigh diffusion +atmospheric model ARLETTY (A. Hauchecorne SA/CNES)  High Resolution Temperature (HRTP) : scintillation obtained with photometers Page 4 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002

Intercomparison of (low resolution) Temperature Page 5 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 AO AO

Intercomparison of (low resolution) Temperature Page 6 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 AO Dist. : 184 km Orb star ID : 155 Mv : 2.9 T : 6600 K

Page 7 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 Intercomparison of (low resolution) Temperature Some statistical results AO GOM_NL__2P* 18 lidar

Intercomparison of (low resolution) Temperature Page 8 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 AO /

Intercomparison of (low resolution) Temperature Page 9 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 AO /

Intercomparison of (low resolution) Temperature Some statistical results Page 10 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 AO GOM_NL__2* 9 radio-soundings

LIDAR RMR Rome Tor Vergata Lidar site: 41.83°N, 12.65°E, 150 a.s.l Laser beam Emission: 532nm,355nm Energy: 220 mJ, 470 mJ Frequency: 10 Hz RECEIVER ARRAY Telescope, 0.15 m Aerosols and Water Vapor in low troposphere Telescope, 0.3 m Raman Temperature, Water Vapor (MIPAS Temperature & H2O validation) 9-Array telescopes 0.5 m (each) Stratospheric aerosols and temperature (GOMOS and MIPAS Temperature validation) Page 11 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002

Intercomparison of H igh R esolution T emperature P rofile Page 12 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 AO GOM_NL__2P* star ID : 52 Mv : 2.04 T : 4500 K Star ID : 142 Mv : 2.85 T : 8900 K

Intercomparison of H igh R esolution T emperature P rofile Page 13 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 AO star ID : 81 Mv : 2.36 T : K Dist. 300 km Time delay : few hours

Page 14 Envisat Validation Workshop, ACVT-GBMCD, GOMOS T 12/12/2002 Conclusions difference of performance between dark/bright limb conditions lack of knowledge of the model contribution in these quantities difficult to validate the HRTP (reflection on the spatio-temporal differences) no bias larger than 10% - good bias lesser than 1% between km seems to be good but the validation must continue