1. 8-years of global observations of water isotopologues in the stratosphere and mesosphere by the Odin satellite J. Urban, D.P. Murtagh, P. Eriksson,... Chalmers University of Technology, Göteborg, Sweden E. Dupuy, Y. Kasai, K. Walker, P. Bernath, G. Stiller, J. Steinwagner,... NICT Koganei, Tokyo, Japan; University of Toronto, Canada; KIT Karlaruhe; University of Utrecht

2. Motivation / Background Water vapour Water vapour Important greenhouse gas in UT/LS Important greenhouse gas in UT/LS Middle atmospheric chemistry (source of HOx) Middle atmospheric chemistry (source of HOx) Main water isotopologues: Main water isotopologues: H2O-16, H2O-18, H2O-17, HDO,... VMSOW: 0.997, 0.00199, 0.00037, 0.0003,... VMSOW: 0.997, 0.00199, 0.00037, 0.0003,... Changes of isotope ratio in the atmosphere: Changes of isotope ratio in the atmosphere: Condensation/evaporation processes (clouds, rain, vertical/horizontal transport) Condensation/evaporation processes (clouds, rain, vertical/horizontal transport) Atmospheric chemistry (e.g. methane oxidation, ozone chemistry) Atmospheric chemistry (e.g. methane oxidation, ozone chemistry)

3. Measurements

4. Microwave limb sounding: major water lines Aura/MLS 183GHz Odin/SMR 489+557GHz UARS/MLS 183GHz MAS/ATLAS (Space Shuttle) JEM/SMILES 1991 200420012009 MLS 183GHz 489GHz557GHz O2 H2O SMR SMILES

5. The Odin satellite Odin - Swedish led mini-satellite, cooperation with Canada, Finland, France. SMR (Sub-Millimetre Radiometer) OSIRIS (Optical Spectrograph and InfraRed Imaging System) Launched in February 2001. 50% astronomy, 50% aeronomy. Limb-sounding in aeronomy mode, Polar sun-synchronous orbit: near global daily coverage.

6. Odin/SMR spectral range H2O, HDO, H2O-18, O3-18 490GHz H2O-17, O3, NO 551GHz ClO, O3, N2O, UTH 501GHz O3, HNO3, H2O, UTH, T 544GHz H2O, O3, T 557GHz CO, O3, T 576GHz Receiver A2 Receiver A1 Receiver B1 Receiver B2

7. Odin/SMR Water Isotope Mode: H 2 O, HDO, H 2 O-18 Chalmers-v2.1 490.4 GHz band 488.9 GHz band ~ 20 km ~ 35 km ~ 50 km H 2 O-16 H 2 O-18 O 3 -16 HDO O 3 -18-sym O 3 -18-asym O 3 -17-asym tropics - 2002-10-26 O 3 -img

8. 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 tropics - 2002-10-26 HDO (4.2S/129.9E) H 2 16 O (0.3S/106.5E) Chalmers-v2.1

9. H 2 O-17 @ 551.7 GHz 21 km 36 km 50 km

10. Odin/SMR 544.6 GHz water vapour tropics: altitude range ~16-25km Lower stratospheric water vapour retrieved from H2O continuum

11. Global distribution

12. Odin water isotope mode 2008 - Sep - 13 2008 - Sep - 5 H2O-16 H2O-18 H2O-17 HDO Maps at 35km!

13. Strato-mesospheric H 2 O-17 / 2007 Chalmers-v2.1 H 2 O-17 @ 551.7 GHz Jul Oct Apr Jan Jul Oct Apr

14. Water isotopes: seasonal averages 2001-2006 15-85 km v2.1 H 2 O HDO H 2 18 O DJF MAM JJA SON 90S EQ 90N 90S EQ 90N 90S EQ 90N

15. Intercomparison with MIPAS and ACE/FTS H2O

16. H2O: comparison Odin, HALOE, ACE - tropics -

17. H2O: comparison Odin, HALOE, MIPAS - tropics -

18. H2O: comparison Odin, HALOE, MIPAS, ACE - tropics -

19. Intercomparison with MIPAS and ACE/FTS HDO

20. HDO zonal mean: ACE/FTS vs Odin/SMR 20ºS-20ºN30ºN-60ºN 70ºN-90ºN [courtesy: Eric Dupuy, K. Walker]

21. HDO: MIPAS - Odin - ACE [comparison: J. Steinwagner] 20km 26km 23km26km 29km32km 35km September - October - November

22. Tape-recorder

23. Odin tropical H2O & HDO "tape-recorder" Chalmers-v2.1 data HDO@490.4GHz daily zonal means Chalmers-v2.0 data H2O@544.6GHz daily zonal means- 10day moving average H2O@488.9GHz Chalmers-v2.1 data daily zonal means - 10day moving average

24. Odin/SMR water isotopologues: 2001-2010

25. Equivalent latitude time-series @ 655K H2O-16H2O-18H2O-17HDO Odin/SMR water isotopologues Chalmers-v2.1 data ~25km

26. Equivalent latitude time-series @ 960K H2O-16H2O-18H2O-17HDO Odin/SMR water isotopologues Chalmers-v2.1 data ~32km

27. Equivalent latitude time-series @ 520K H2O-16H2O-18H2O-17HDO Odin/SMR water isotopologues Chalmers-v2.1 data ~21km

28. Odin/SMR H2O-16 @ 655K H2O@488.9GHz / Chalmers v2.1

29. Odin/SMR H2O-18 @ 655K H2O-18@488.9GHz / Chalmers v2.1

30. Odin/SMR H2O-17 @ 655K H2O@551.7GHz / Chalmers v2.1

31. Odin/SMR HDO @ 655K HDO@490.4GHz / Chalmers v2.1

32. Polar winter descent Polar winter descent

33. H2O-18 @ 488.9GHz time-series: high latitudes Water isotope mode IM_AC2ab, IM_AC2c target species: H2O, H2O-18, HDO 2001-2008 ~1 observation day per week smoothed over 30 days zonal averages 70-90S, 70-90N SH NHH2O-18 anomaly VMR

34. Odin/SMR H2O-18 at high eqv. latitudes 1200K 840K 655K 520K

35. Time-series

36. Odin water isotopes: 2001-2010 tropics, zonal mean Evolution of Odin/SMR water isotopes H2O 475-825K ( ~20-30km) HALOE H2O Odin H2O 544.6GHz Odin H2O 488.9GHz Odin HDO Odin H2O-17 Odin H2O-18 ACE H2O ACE HDO MIPAS H2O H2O 825-1400K ( ~30-40km) H2O 375-425K ( ~16.5-18.5km) H2O 425-475K ( ~18.5-20.5km)

37. Evolution of Odin/SMR water isotopes H2O 375-425K ( ~16.5-18.5km) H2O 475-825K ( ~20-30km) HALOE H2O Odin H2O 544.6GHz Odin H2O 488.9GHz Odin HDO Odin H2O-17 Odin H2O-18 ACE H2O ACE HDO MIPAS H2O Odin water isotopes: 2001-2010 tropics, zonal mean H2O 825-1400K ( ~30-40km)

38. Odin water isotopes: 2001-2010 tropics, zonal mean Evolution of Odin/SMR water isotopes H2O 475-825K ( ~20-30km) HALOE H2O Odin H2O 544.6GHz Odin H2O 488.9GHz Odin HDO Odin H2O-17 Odin H2O-18 ACE H2O ACE HDO MIPAS H2O H2O 825-1400K ( ~30-40km) H2O 375-425K ( ~16.5-18.5km)

39. H2O evolution / tropics

40. Water vapour / 30°S to 30°N / 25-35 km SAGE Odin/SMR HALOE Aura/MLS H2O anomaly [%] Year [Jones et al., ACP-2009] 1984-2008 - deseasonalized and combined data sets green: all instrument weighted mean

41. Odin carrying SMR (Sub-Millimetre Radiometer) launched in February 2001 now: ~9 years of observations starting from Nov 2001 (quasi-global coverage). now: ~9 years of observations starting from Nov 2001 (quasi-global coverage). Continued operation through 2010 (ESA third party mission, 100% aeronomy). Strato-mesospheric water vapour isotopologues: Strato-mesospheric water vapour isotopologues: H 2 O, HDO, H 2 O-18, O 3 -isotopes around 490GHz: H 2 O, HDO, H 2 O-18, O 3 -isotopes around 490GHz: ~4 days / month, Nov 2001 -, strat-mesosphere (~18/20-75km), now ~8 days / month H 2 O-17, NO, O 3, T at 551GHz: H 2 O-17, NO, O 3, T at 551GHz: ~1 day / month, Oct 2003 -, strat-mesosphere (~20-75km), now ~4 days / month Odin/SMR operational level-2 data: Chalmers-v2.1. Quality assessment ongoing, e.g. MIPAS and ACE (H2O, HDO) intercomparisonSummary

42. Summary: Odin H2O assessment (strat.) Odin stratospheric water vapour products: Odin stratospheric water vapour products: 1. Lower stratospheric H2O at ~16-20km: 544.6GHz (v2.0) H2O@544.6GHz agrees well with HALOE in 375-425K (~16-19km) range, but biased low at 425-500K (and not useful above). 2.Strato-mesospheric H2O, ~20-75km: 488.9GHz (v2.1) H2O@488.9GHz agrees with HALOE in 500-1000K (~21-30km) range, but generally lower than ACE and CFH sondes. Low biased in middle and upper stratosphere and mesosphere. 3.Strato-mesospheric HDO, ~18-70km: 490.4GHz (v2.1) HDO@490.4GHz shows negative bias compared to MIPAS and ACE in the (18-35km) range covered by the IR measurements. 4.Strato-mesospheric H2O-18, ~20-70km: 488.9GHz (v2.1) 5.Strato-mesospheric H2O-17, ~20-80km: 551.7GHz (v2.1) no correlative data no correlative data H2O-16: Similar (seasonal, QBO) variability as HALOE, MIPAS, ACE in the relevant layers 375-425K (544.6GHz) and 500-1000K (488.9GHz). H2O-16: Similar (seasonal, QBO) variability as HALOE, MIPAS, ACE in the relevant layers 375-425K (544.6GHz) and 500-1000K (488.9GHz).

43. Thank you!