1. SISS seminar, Roma 19 Nov 2007 La ricerca aerea nella Alta Troposfera e Bassa Stratosfera Tropicale Una sintesi dell'attivita' dell'aereo Geophysica Francesco Cairo

2. SISS seminar, Roma 19 Nov 2007 The M-55 Geophysica is the only high altitude aircraft available for research for the European Scientific Community. It is a dual turbofan aircraft with a ceiling of 21 km; it can transport a payload up to 2300Kg, has an endurance, with a nominal payload of 1500 Kg and a cruise altitude of 17.5 km, of 5.5 hours, 60 KVA are available for instrument operations.

3. SISS seminar, Roma 19 Nov 2007 List of scientific instruments which can be hosted on the M-55 Geophysica #Instrument nameInstrument typeSpecies detectedInstitute 1CIPCloud Particle ImagerCloud particles 4-2000 umUniversity of Mainz 2GASCOD-AUV-Vis spectrometerO3, NO2, OClO, BrOISAC-CNR 3MASMulti-wavelength Aerosol Scatterometer backscatter coefficientISAC-CNR 4FSSP-300100optical aerosol counterAerosol size distributionUni. Mainz 5MuLidMicrojoule Lidarbackscatter coefficientObservatoire Neuchatel 6TDL-TIRISTDL to measure isotopes of H2OH2O isotopesUniv. Groeningen 7ECOCElectroChemical Ozone CellO 3 in situ measurementsCAO 8FLASHFluorescent hygrometerstratospheric water vapourCAO 9ACHCondensation hygrometertropospheric water vapourCAO 10WASH2O isotopes samplerH2O isotopesUniversity of Utecht Microjoule Lidr Microjoule Lidr

4. SISS seminar, Roma 19 Nov 2007 11FISHFluorescent hygrometerstratospheric water vapourFZJ 12COPASCOndensation PArticle detection System counts particles between 10 nm and 10 micrometers Uni. Mainz 13HAGAR Gas ChromatographN2O, SF6, CFC-12, CFC-11, CH 4 Uni. Frankfurt 14HALOX-AChemical-Conversion Resonance-Fluorescence In Situ ClO and BrOFZJ 15SIOUXNO/NOyNO and NOy in situDLR 16FOXUV O 3 sensorO 3 concentrationDLR 17COLDTDLCO in situINOA 18ALTOTDLCH 4 in situINOA 19RosemountPressure, TemperatureP, T in situCAO 20MIPASFFTMIRS O 3, CFCs, CCl4, H2O, CH4, OCS, HNO3, NO, N2O5, ClONO2 FZK 21MARSCHALSMillimetre spectrometerO 3, H 2 O, CO, HNO 3, N 2 OCCLRC-RAL 22CRISTAFar Infrared SpectrometerO 3, H 2 O, CO, HNO 3, N 2 OFZJ

5. SISS seminar, Roma 19 Nov 2007 Water vapour circulation in the UT-LS Adapted from Haynes, 2004 Stratosphere Lowermoststratosphere Troposphere Upper Troposphere Lower Stratosphere 6-22 km height CH4 Source via photolysis - “Trap Mechanism” - Cold Point… - Fast localised ascent or TTL transport ? - Cirrus condensation…

6. SISS seminar, Roma 19 Nov 2007 H 2 O UTLS Trends Randell, JAS 2004 - Positive trend measured by Frost-Point soundings in Boulder (SPARC, 2000) - Recent assessment of HALOE –UARS H2O data show a negative trend during last 5 years (Randell, 2004) - H 2 O anomalies are correlated with decrease in tropical tropopause temperature - CPL variability is correlated with QBO and is also driven by ENSO (i.e 1997)

7. SISS seminar, Roma 19 Nov 2007 Climatic role of water vapor in the stratosphere - Radiative effect (net cooling) ( + H2O  - T ) - Main source for HOx (OH+HO2) - HOx is also the principal family which destroys O3 in the lower stratosphere ( + H2O  + O3 loss  - T ) - H2O is a key component of Polar Stratospheric Clouds ( + H2O  + PSC  + O3 loss  - T) - H2O PSC dehydrate the Antarctic (Arctic ?) polar stratosphere (+ H2O PSC  + Dehydration  - O3 loss  + T )

8. SISS seminar, Roma 19 Nov 2007 H 2 O Measurements in the UTLS - Radiosoundings have a bias above 5 km due to low temperatures - Accurate ground-based and in-situ measurements (Lyman, Frost point, Lidars) are not operated routinely - Microwave profilers are not sensitives below 25 km - Nadir Satellite measurements are masked by high lower tropospheric H2O - Satellite Profilers are difficult to operate and retrievals in the UTLS are tricky Tropopause Ground Lower Strat RSLy-FPLidarMu-wSAT

9. SISS seminar, Roma 19 Nov 2007 Processes in the Tropical Tropopause Region Secondary TP ~345K max. avg. conv. outflow TTL Stratospheric Subtropical barrier Troposphere Cold Point TP ~380K Subtropics latitude Isolated tropical stratosphere clear-sky heating = 0 ~360-370K

10. SISS seminar, Roma 19 Nov 2007 Menu’ Tropical Cirrus Clouds Overshooting Cbs Water balance UTLS horizontal transport What will be missing: NOy, lightning NOx, aerosol production and fate, ozone chemistry

11. SISS seminar, Roma 19 Nov 2007 M55 Geophysica Observations in the Tropical UTLS MissionTimeRegionCharacteristics tropical flights APE-THESEO2-3/ 1999 Indian Ocean non-convective7 APE-GAIA Transfer 9&10/ 1999 Atlantic non-convective4 TroCCiNOx + Transfer 1-2/2005 S Brasil Atlantic continental convection, mostly subtropical 8484 SCOUT-O3 + Transfer 11-12/ 2005 Maritime Continent maritime convection, Hector 9898 AMMA-SCOUT + Transfer 8/2006 West Africa continental convection 6262

12. SISS seminar, Roma 19 Nov 2007 The Seychelles: we went for Cbs and got cirrus instead… Santacesaria et al., JGR 2003 Stefanutti et al. JAC 2004

13. SISS seminar, Roma 19 Nov 2007 Santacesaria et al., JGR 2003 Cirrus formation mechanisms: a case study 24 hrs backtrajectories

14. SISS seminar, Roma 19 Nov 2007 Peter et al. ACP 2003 The “less than subvisible” cirrus clouds

15. SISS seminar, Roma 19 Nov 2007 Luo et al., GRL 2003 Thomas et al. JGR 2002

16. SISS seminar, Roma 19 Nov 2007 Luo et al. ACP 2003

17. SISS seminar, Roma 19 Nov 2007 Brasil and Darwin: overshootings above CP! (Cairo F., CNR)

18. SISS seminar, Roma 19 Nov 2007 STEP-Tropical Ice water content derived from two Ly-  hygrometers Ice water content derived from FISH and FLASH 7 flights in Brazil and Australia STEP-Tropical 1987 8 flights Kelly et al., JGR, 1993

19. SISS seminar, Roma 19 Nov 2007 In situ formation? Assume 130 % RH over ice. Supersaturation required / subsaturation observed Particles would have to nucleate above 22 km and grow for 1 h to reach the observed 100 μm. (Th. Peter, ETHZ) (S. Borrmann, UniMainz)

20. SISS seminar, Roma 19 Nov 2007 Contrail sampling? wake vortices UCSE / ECMWF wind 1)Contrail tracking using UCSE winds and from ECMWF operational data. 2)Contrail spreading using wake vortex model. About 3 % of the ice particle observations might have originated from contrail sampling and are excluded. (Th. Peter, ETHZ)

21. SISS seminar, Roma 19 Nov 2007 Convective transport? Background profile Ascending air parcel Mixing Ascent of an air parcel in deep convection (moist adiabatic) assuming no friction. Overshooting to ~20 km LNB 170 190 210 230 250 270 290 T [K] (Th. Peter, ETHZ)

22. SISS seminar, Roma 19 Nov 2007

23. Modelling sedimentation / evaporation of observed ice particles Typical: r < 15 μm  evaporation in the stratosphere r > 40 μm  sedimentation into the troposphere 380 K 10  m20  m 50  m Flight level RHI = 50-75 % as measured (Th. Peter, ETHZ)

24. SISS seminar, Roma 19 Nov 2007 observed strat. particulate H 2 O expected to evaporate above 380 K  0.5–2 ppmv depending on case  on average 1 ppm H 2 O 32103210 3 5 10 20 50 100 Initial particle radius [μm] Particulate water [ppmv per bin] evaporating in strat sedimenting back to trop How much of the particulate H 2 O stays actually in the stratosphere? (Th. Peter, ETHZ)

25. SISS seminar, Roma 19 Nov 2007 (Corti et al., ETHZ, Manuscript in preparation) FISH data, filtered: No particles, i.e. CIP & FSSP = 0, MAS < 1.25), FISH and FLASH agree within  10 % No evidence for convectively induced dehydration

26. SISS seminar, Roma 19 Nov 2007 (Chaboureau et al., ACP 2007)

27. SISS seminar, Roma 19 Nov 2007 Mixing of overshooting air in the TTL: AMMA Mixing ? Ulanowsky, CAO; Ravegnani, CNR; Volk, UNI-Frankfurt; Viciani, CNR

28. SISS seminar, Roma 19 Nov 2007 Water and particles during AMMA- SCOUT (west Africa) Schiller, FZJ Cairo, CNR Enhanced backscattering but no depolarization hydrated layers

29. SISS seminar, Roma 19 Nov 2007 Conclusions Cirrus clouds: potential to dehydrate airmass as it is uplifted to the stratosphere. Potentially important for radiative heating, to “speed up” the air uplift in the TTL. Convection: Max. average outflow level @ 360 K or 14-15 km, but signature of vertical mixing following convective overshooting Hydration by overshooting ice particles over land convective systems Dehydration by condensation at low temperature along airmass trajectory (colder in NH winter than NH summer) Upscaling and balance of these two processes, under debate.

30. SISS seminar, Roma 19 Nov 2007 Horizontal mixing into tropical LS: Vertical N 2 O distribution APE-THESEO: mostly inside tropical pipe C. M. Volk, Uni-Frankfurt

31. SISS seminar, Roma 19 Nov 2007 TROCCINOX: outside tropical pipe, mixing region Horizontal mixing into tropical LS: Vertical N 2 O distribution C. M. Volk, Uni-Frankfurt

32. SISS seminar, Roma 19 Nov 2007 SCOUT-O3: somewhere in between Horizontal mixing into tropical LS: Vertical N 2 O distribution C. M. Volk, Uni-Frankfurt

33. SISS seminar, Roma 19 Nov 2007 Comparison with previous tropical campaigns: Stratosphere AMMA/SCOUT-O3: 060813 flight inside tropical pipe C. M. Volk, Uni-Frankfurt

34. SISS seminar, Roma 19 Nov 2007 APE-THESEO: mostly inside tropical pipe Horizontal mixing into tropical LS: O 3 -N 2 O correlation C. M. Volk, Uni-Frankfurt

35. SISS seminar, Roma 19 Nov 2007 TROCCINOX: outside tropical pipe, mixing region Horizontal mixing into tropical LS: O 3 -N 2 O correlation C. M. Volk, Uni-Frankfurt

36. SISS seminar, Roma 19 Nov 2007 SCOUT-O3: somewhere in between Horizontal mixing into tropical LS: O 3 -N 2 O correlation C. M. Volk, Uni-Frankfurt

37. SISS seminar, Roma 19 Nov 2007 Comparison with previous tropical campaigns: Stratosphere AMMA/SCOUT-O3: 060813 flight inside tropical pipe C. M. Volk, Uni-Frankfurt

38. SISS seminar, Roma 19 Nov 2007 TROC. SCOUT THESEO APE-THESEO Climatological Context of campaigns: Tropical Pipe (@ 500K) Meridional PV gradient is a measure for inhibition of isentropic mixing AMMA C. M. Volk, Uni-Frankfurt

39. SISS seminar, Roma 19 Nov 2007 Konoptka et al., ACP 2007 Close to the STJ: stratospheric intrusion into the TTL

40. SISS seminar, Roma 19 Nov 2007 Close to the STJ: Troposphere to Stratosphere Transport Konoptka et al., ACP 2007

41. SISS seminar, Roma 19 Nov 2007 Transport across the STJ: In addition to advective isentropic mixing, an upward transport of trace species across the TTL may be achieved by diffusive irreversible mixing induced by enhanced shears/strains close to the STJ

42. SISS seminar, Roma 19 Nov 2007 SCOUT-O3 „background TTL“ O3 Profiles Ulanowsky, CAO; Ravegnani, CNR; Volk, UNI-Frankfurt;

43. SISS seminar, Roma 19 Nov 2007 SCOUT-O3 background and „mixed“ O3 profiles Elevated TTL O3 due to vertical mixing Ulanowsky, CAO; Ravegnani, CNR; Volk, UNI-Frankfurt;

44. SISS seminar, Roma 19 Nov 2007 SCOUT-O3 and AMMA-SCOUT O3 profiles Elevated TTL O3 due to -Vertical mixing along STJ ? -O3 production ? Ulanowsky, CAO; Ravegnani, CNR; Volk, UNI-Frankfurt;

45. SISS seminar, Roma 19 Nov 2007 Conclusions Tropical Stratospheric transport: Brasil as a region of active mixing, Darwin and West Africa more isolated, Seychelles well within. Stratosphere active and inactive in terms of isentropic mixing across the subtropics, according to time and geographical location. Tropical Pipe generally “leaky”. TTL: Diffusive fluxes across the STJ may contribute to the transport across the TTL and the tropopause. O3 throughout TTL a factor 2 higher in Africa than in other places, still to be investigated.

46. SISS seminar, Roma 19 Nov 2007 An aknowledgement to The heroes of the story: Oleg… …and Oleg.