1. Workshop on Active Protection of Passive Radio Services – 28-29 October 2004 – Cagliari (Italy) Limb observations of the middle atmosphere at sub-mm wavelengths: Odin/SMR and future sensors J. Urban, D. Murtagh … and the Odin team Chalmers University of Technology, Göteborg (Sweden) Chalmers University of Technology, Göteborg (Sweden)

2. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Overview  Odin / Sub-Millimetre Radiometer  Odin/SMR observation modes:  Stratospheric mode  Water isotope mode  Mesospheric observations  Future sub-mm limb sensors

3. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin / Sub-Millimetre Radiometer

4. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) The Odin satellite Swedish led mini-satellite. Cooperation with Canada, Finland, France. Launched in February 2001. Design lifetime: 2 years. Circular quasi-polar sun-synchronous orbit: 625km altitude, 96min/orbit, 6h/18h equator crossing. Time sharing: 50% astronomy, 50% aeronomy. Limb-sounding in aeronomy mode: ~45-65 scans/orbit (~14 orbits/day) 2 instruments: SMR (Sub-Millimetre Radiometer), OSIRIS (Optical Spectrograph and Infrared Imaging System) Aeronomy science objectives: stratosphere + mesosphere. Aeronomy science objectives: stratosphere + mesosphere. stratospheric mode (ClO, N 2 O, HNO 3, O 3 ), water isotope mode (H 2 O, HDO, H 2 O-18, H 2 O-17), stratospheric mode (ClO, N 2 O, HNO 3, O 3 ), water isotope mode (H 2 O, HDO, H 2 O-18, H 2 O-17), odd hydrogen / summer mesosphere mode (H 2 O, O 3, CO), odd nitrogen mode (NO, HNO 3, NO 2 ) odd hydrogen / summer mesosphere mode (H 2 O, O 3, CO), odd nitrogen mode (NO, HNO 3, NO 2 )

5. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin Sub-Millimetre Radiometer  4 sub-mm (ssb) radiometers in 485-580 GHz range, 1 mm channel at ~119 GHz.  1.1 m telescope.  2 auto-correlators, 1 acousto-optical spectrometer, 1 (3 channel) filter-bank. A1: 541-558 GHz B1: 563-581 GHz B2: 547-564 GHz C: 119 GHz A2: 486-504 GHz Atmospheric Signal The Odin Sub-Millimetre Radiometer [Frisk et al., A&A, 402, 3, 2003]

6. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR frequency coverage Swedish Space Corporation

7. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR observation modes ClO, N 2 O, O 3 O 3, HNO 3 7-70 km H 2 O, H 2 O-18, O 3 HDO, O 3 -18 7-110 km Stratospheric Mode Water Isotope Mode Strat-scan Stratmeso-scan H 2 O, O 3 (mesosphere) ~4 days / month ~10 days / month Strat-meso mode H 2 O, O 3, CO Stratmeso-scan ~1 day / month Stratmeso-scan Odd hydrogen mode H 2 O, O 3, CO, HO 2 ~1 day / month

8. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR stratospheric mode

9. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR Stratospheric Mode: N 2 O, ClO, O 3 @ 501.8 GHz Antarctic polar vortex - 78.4S/143.8ENorthern mid-latitudes – 30.4N/346.1E20-Sep 2002 ~ 18 km ~ 25 km ~ 32 km N2ON2O ~ 40 km CTSO-v223-offline N2ON2O ClO O3O3 O3O3

10. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR Stratospheric Mode: ClO @ 501.3 GHz Antarctic polar vortex - 78.4S/143.8ENorthern mid-latitudes – 30.4N/346.1E 20 September 2002 CTSO-v223-offline

11. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR Stratospheric Mode: O 3 and HNO 3 @ 544.6 GHz O3O3 CTSO-v223-offline Antarctic polar vortex - 78.4S/143.8ENorthern mid-latitudes – 30.4N/346.1E20-Sep 2002 ~ 18 km ~ 25 km ~ 32 km ~ 40 km CTSO-v223-offline O3O3 HNO 3

12. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) O 3 N 2 O ClO 501.8 GHz band O 3 HNO 3 544.6 GHz band 20-21 March 2003 Odin/SMR stratospheric mode: level 2 product / zonal mean

13. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Arctic vortex 2002-03 @ 525K T N2ON2O ClO O3O3 (ECMWF) 9-10 Nov9-10 Dec13-14 Jan 19 Jan23Jan9-10 Feb18-19 Feb23-24 Mar [Urban et al., GRL 31(7), 2004]

14. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR water isotope mode

15. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Strato-mesospheric Water Vapour High concentration in troposphere. Enters stratosphere through TTL (cold trap): dry air in stratosphere. Relatively long-lived in stratosphere: distribution governed by global circulation. Seasonal variations due to variations of T tropopause : tape recorder effect. Chemical production in stratosphere: methane oxydation. Sinks in middle atmosphere: photodissociation, reaction with O( 1 D), OH. Radiative balance of climate system: most important greenhouse gas, indirect processes through cloud formation Middle atmospheric chemistry: source gas of HO x -family, controlling O 3 - destruction in upper stratosphere and mesosphere

16. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Stratospheric Water Vapour Sinks: H 2 O + h  H + OH H 2 O + h  H 2 + O( 1 D) H 2 O + O( 1 D)  OH + OH Tropospheric Air CH 4 +OH  H 2 O + CH 3 CH 4 + O( 1 D)  …  H 2 O Sources: Increase of ~1% / year in the stratosphere over the last decades (Oltmans et al. 2000, Rosenlof et al. 2001, Nedoluha et al. 2003) Possible effects on ozone and climate (Kirk-Davidoff et al. 1999, Shindell 2001, MacKenzie and Harwood 2004)

17. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR water isotope mode Spectra + fit for H 2 16 O, H 2 18 O, and O 3 – band 488.35-489.35 GHz H2OH2O H 2 18 O O3O3

18. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Spectra + fit for HDO and 18 O 3 – band 489.95-490.75 GHz HDO 18 O 3 Odin/SMR water isotope mode

19. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR water isotope mode Retrieved profiles of H 2 16 O @ 488.9 GHz and HDO @ 490.4 GHz Simultaneous retrieval of H 2 16 O, O 3, H 2 18 O / HDO, 18 O 3 -asym, 18 O 3 -sym, scan-bias, linear baseline (offset), temperature, and continuum HDOH 2 16 O

20. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR water vapour – 15 Dec 2001 Retrieval of water vapour H 2 16 O - band 488.35-489.35 GHz zonal mean and global distribution 24 hours = 14 orbits x 50 scans / orbit zonal mean H 2 16 OH 2 16 O at 30km

21. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR water isotope mode: H 2 O, HDO, Odin/SMR water isotope mode: H 2 O, HDO, δD 29-30 April 2002 26-27 October 2002 H 2 O @ 488.9 GHz HDO @ 490.4 GHz δD (HDO) Zonal mean of water vapour H 2 16 O and its isotope HDO

22. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR mesospheric modes

23. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Strato-mesospheric carbon monoxide  Sources: CO 2 photolysis (mesosphere + thermosphere), minor chemical source: CH 4 oxidation (stratosphere).  Chemical sinks:  Chemical sinks: CO + OH → CO 2 + H  Lifetime: comparable or longer than typical transport timescales, e.g. ~ 1 week around 50 km   transport processes dominate the CO distribution in most of the middle atmosphere  tracer for global meridional circulation, coupling of troposphere-stratosphere- mesosphere, …  Global observations: 4.6 μm IR emission: UARS/ISAMS (~6 month in 1991-92), Envisat/MIPAS (6/2002-3/04), mm/sub-mm emission: Odin/SMR (several days since Aug 2001), AURA/MLS (?/2004-).

24. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) CO data analysis  Global measurements: CO (J=5→4) @ 576.268 GHz –Strat-meso scan (7-110 km)→ 7 Aug + 18 Nov 2001, 18 Nov 02, ~1-3 day/month since Oct 03; –Summer-meso scan (55-110 km) → 2-14 July 2002, -04).  LO-failure of 572 GHz radiometer  correction for frequency shift!  Profile retrieval: altitude range ~20-110 km, resolution ~3 km, single-profile precision 10-25 %. 7 Aug 2001 – 3N/120W [Dupuy et al., GRL 2004, accepted]

25. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Global CO data: seasonal variation CO 7-8 Aug 2001 CO 18-19 Nov 2001 N 2 O 24-25 Nov 2001 N 2 O 5 Aug 2001

26. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Simulation of limb-scan between 0 and 90 km H 2 O line at 556.9 GHz (most intense line between 0 and 1 THz) Mesospheric water vapour H2OH2O O3O3 H2OH2O H2OH2OH2OH2O O3O3 O3O3 39 km 82 km 60 km 49 km

27. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Odin/SMR H2O @ 556.9 GHz Non-linear retrieval based on OEM Altitude range: ~33 to 90 km Simultaneous Retrieval of (x=): H 2 O profile other lines present in the bandwidth (O 3, HNO 3 ) temperature continuum instrumental baseline pointing bias 45 132 123 45

28. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Present and future missions  STEAM – Stratosphere-Troposphere Exchange And climate Monitor (proposed)  Aura / MLS – Microwave Limb Sounder on Aura (launched 15 July 2004)  ISS: JEM / SMILES – Japanese Experiment Module / Sub-Millimeter Limb Emission Sounder (planned for launch in 2008)

29. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Scientific Objectives  Climate Evolution –Detailed measurements of upper tropospheric H 2 O –IPCC identified lack of knowledge of the water vapour cycle particularly in the upper and middle troposphere as a major uncertainty in climate models –Water feedback provides a doubling of the CO 2 temperature increase in current climate models  Stratosphere-Troposphere Exchange –Highly spatially resolved measurements of O 3, H 2 O and CO  Ozone Changes –Continued surveillance of ozone and ClO in post Odin and EOS-Aura era STEAM – Stratosphere-Troposphere Exchange And climate Monitor

30. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Preliminaries  Swedish-Canadian-French concept  Odin heritage in hardware [microwave (SMR) and UV/VIS-IR (OSIRIS)], human and science  Microwave instrument: 2 channels: –320 GHz: H 2 O, O 3, CO and N 2 O  UT/LS –500 GHz: O 3, ClO, H 2 O and isotopes  stratosphere  Optical / near infrared instrument: –to complement the microwave instrument and improve the microwave measurement analysis in the presence of clouds –8 channels: 450 nm-1.3 µm –O 3, H 2 O, aerosol and cloud property (UT/LS) –Stratospheric O 3  Limb imaging (multi-beam) observation scheme and 2-d tomographic retrieval concept for high vertical and horizontal resolution  SWIFT - Stratospheric Wind Interferometer For Transport studies (?) STEAM – Stratosphere-Troposphere Exchange And climate Monitor

31. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) mm-Channel (UT/LS) STEAM – Stratosphere-Troposphere Exchange And climate Monitor

32. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) STEAM retrievals: mm-channel  cloud-free atmosphere  1-D retrievals (as for Odin)  tropopause: 12 km STEAM – Stratosphere-Troposphere Exchange And climate Monitor

33. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Sub-mm Channel (Stratosphere) Odin Windows STEAM – Stratosphere-Troposphere Exchange And climate Monitor

34. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Microwave Limb Sounder on EOS Aura EOS Aura Satellite launched on 15 July 2004. Latitude coverage from 82 o S-82 o N. 3495 profiles per day 6 year lifetime W. Read - JPL

35. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) EOS/MLS Spectral Coverage OH 190 GHz 240 GHz 640 GHz 2.5 THz 119 GHz ClO N2ON2O HCl OH CO H2OH2O N2ON2O O2O2 W. Read - JPL

36. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Y. Kasai, NICT, Tokyo

37. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) JEM/SMILES - frequency bands Y. Kasai, NICT, Tokyo

38. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Summary / Conclusions / Perspectives Limb-sounding at sub-mm wavelengths well established tool for middle atmospheric research:  Odin carrying SMR (Sub-Millimetre Radiometer) launched in February 2001. –frequency range: ~485-580 GHz (4 tuneable sub-mm SSB radiometer), 119 GHz –now: ~3 years of observations starting from Nov 2001 (quasi-global coverage). –50% astronomy, 50% aeronomy, –aeronomy mode: stratospheric and mesospheric research objectives.  Microwave Limb Sounder (MLS) launched on 15 July 2004 (EOS/AURA satellite). –Radiometers at 119, 190, 240, 640, and 2500 GHz (DSB), –Research focus on UT/LS and stratosphere.  JEM/SMILES (Sub-millimeter Limb Emission Sounder) on Int. Space Station. –to be launched in 2007 (?), –SIS receiver (SSB), 2 bands around 625 and 649 GHz, stratospheric target species.  Proposed sub-mm instruments for UT/LS research: –STEAM – Stratosphere-Troposphere Exchange And climate Monitor –MASTER (+ Marschals, airborne demonstrator) Wideband (8-12 GHz) channels in ~320-360 GHz range for UT/LS sounding, stratospheric channels around ~488-505 GHz.

39. Workshop on Active Protection of Passive Radio Services 28-29 October 2004 – Cagliari (Italy) Acknowledgments  Odin/SMR retrieval group : E. Le Flochmoën, J. De La Noë, E. Dupuy, L. El Amraoui, F. Jégou, P. Ricaud Observatoire Aquitain des Sciences de l’Univers, L3AB, Floirac, France J. Urban, N. Lautié, C. Jiménez, P. Eriksson, D. Murtagh, M. Olberg Chalmers University of Technology, Göteborg, Sweden U. Frisk Swedish Space Corporation, Solna, Sweden Odin is a Swedish-led satellite project funded jointly by the Swedish National Space Board (SNSB), the Canadian Space Agency (CSA), the National Technology Agency of Finland (Tekes) and the French Centre National d’Études Spatiales (CNES). … also thanks to Y. Kasai, Communications Research Laboratory (Tokyo, Japan) W. Read, Jet Propulsion Laboratory (Pasadena, USA)