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Central Aerological Observatory. FLASH-B FL uorescent A dvanced S tratospheric H ygrometer (for balloon and aircraft). Khaykin S., Yushkov V., Korshunov L., Lukyanov A. Instrument design. Observations and comparison. ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern.
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Central Aerological Observatory FLASH-BFLuorescentAdvanced Stratospheric Hygrometer(for balloon and aircraft) Khaykin S., Yushkov V., Korshunov L., Lukyanov A. Instrument design. Observations and comparison. ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern
ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern Balloon FLASH=B uses open optical cell Night time measurements Short balloon & long duration balloon Aircraft FLASH-B uses closed optical cell Day&night time mesurements
ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern FLASH-B instrument
at P > 7 hPa Н(2S) h =121,6 nm (Lyman-α) Source of VUV radiation Н2О PMT Н2О + h ОН (А2+) + Н(2S) 300 < λ < 330 nm ОН (А2+) ОН (Х2П ) Fluorescense ОН (А2+) ОН (Х2П) + h’ Quenching ОН (А2+) + N2, О2 products Ifl – fluorescense intensity J-photodissotiation rate φ= 0,05 - quantum efficiency for excited OH production А=1,26106s-1 – Einstein coefficient, kqair. = 2,310-11sm3s-1 – quenching coefficient of the excited OH in air [H2O] I fl = Scal-------- [ air]
Photomultiplier FLASH-B optical layout
Electronic block-layout of FLASH-B VUV lamp Lyman-alpha Lamp 1 KHz 121,6 nm OSC driver H O 2 OH* Interference 310 nm PMT filter power Photomultiplier VAISALA P, T, U RS-80 Synchrofilter microcontroller radiosonde Synchrodetector Data frame PC Receiver Modem ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern
Calibration facility layout homogenizer flow controller flow controller FLASH-B Reference dew point mirror hygrometer Pressure: 3 ..1100 hPa Temperature: -80 .. +20 0C WVMR: 1 .. 1000 ppmv dehumidifier H2O bubbler air out MBW 373L Vacuum chamber Vacuum pump Compressor
ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern FLASH-B characteristics
Measurement sites since winter 2004 Ny-Alesund Sodankylä Lindenberg
Intercomparison of FLASH-B and NOAA/CMDL hygrometers in the stratosphere Descent data only Mean difference in the 11,8 – 25,6 km range is: 2.6 ±3.1 % (1 σ) Large disagreement in the 8,8 – 11,8 km range is caused by the feedback gain change in the NOAA hygrometer
Comparison of in-situ balloon-borne and remote microwave water vapour measurements Comparison of MIAWARA (solid grey), NOAA(dashed black)/CU-CFH (dashed-dottedblack) and FLASH-B (solid black) (balloon descent) profiles for different days. The black dots are measurementsby NOAA/CU-CFH which were not considered due to remaining wet contamination from the ascent or instrumental failure. The balloon profiles were reduced to the microwave retrieval grid using the Curtis - Godson equation. The CU-CFH sonde was flown on Feb-15 and Feb-25, on the other flightsthe older NOAA version was used. B. Deuber et al., 2005, JGR
Simultaneous humidity measurements in the troposphere during LAUTLOS 11 February 2004
Simultaneous humidity measurements in the troposphere during LAUTLOS 23 February 2004
Water vapour profiles inside, otside and at the edge of polar vortex during LAUTLOS campaign (Sodankyla, Jan-Feb 2004).
SCOUT-AMMA balloon campaign. Local convection on 23 August 20 15 10 5 Hydration of LS by ice geysers C-band radar cloud tops height at 16:51 UT on 23 August, two hours before the sounding from Niamey
NASA TC4 campaign, Costa-Rica, 100 N, August 2007 (sonde programme): simulataneous measurements of water vapour and ozone by FLASH-B and CFH hygro-sondes.
NASA TC4 campaign, Costa-Rica, 100 N, August 2007 (sonde programme): simulataneous measurements of water vapour and ozone by FLASH-B and CFH hygro-sondes. Comparison between FLASH-B and CFH H2O descent profiles Mean relative difference in the 10% range
ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern Comparison between FLASH-B and ECMWF Arctic
ISSI”Atmospheric Water Vapour” 10-15 Febr.2008 Bern Comparison between FLASH-B and ECMWF Tropics
SCOUT-O3 Darwin, Australia, 120 S, November 2005 H2O and O3 measurements with FISH on board M55-Geophysica incl. convection Courtesy of C. Schiller tropopause (17 km): cold point and cold trap
SCOUT-O3 Darwin, Australia, 120 S, November 2005 H2O and O3 measurements with FLASH and FOZAN on board M55-Geophysica 16 November Well mixed dry air between LRT and CPT CPT No signs of hydration in LS above Hector LRT Warmer T and higher O3 in LS above Hector
SCOUT-O3 Darwin, Australia, 120 S, November 2005 H2O and O3 measurements with FLASH and FOZAN on board M55-Geophysica H2O, temperature and O3 profiles above Darwin No signs of hydration in LS above Hector Enhanced ozone inside Hector Dry and mixed TTL with H2O amounts controlled by saturation at CPT
Ice geyser hydration across the tropopause may be the dominant factor controlling water vapour at global scale in the stratosphere. Concluding remarks • WVMR observations above Darwin do not show strong signatures of LS hydration above Hector H2O, O3 and particles measurements above Africa during monsoon season strongly indicate that convective overshooting above continental region hydrates lower stratosphere • Ice geyser hydration across the tropopause may be the dominant factor controlling water vapour at global scale in the stratosphere.
FLASH-B on board long duration super pressure balloon CNES SPB mission in Esrange, Kiruna, Sweden (March 2007) 1st day of flight – contamination from the payload 5th day of flight – dry payload, no contamination
FLASH-B on board long duration super pressure balloon CNES SPB mission in Esrange, Kiruna, Sweden (March 2007) 12 m2 CNES SP balloon launched from Esrange on 05.03.2007 8 days flight around the pole inside vortex FLASH-B in the bottom of flight train 15 minutes measurements every 2 hours during night time Landing and recovery in Sweden
Simultaneous humidity measurements in the troposphere during Scout-AMMA
FLASH-B water vapour observations in the presence of PSCs Ny-Alesund (78,9 N, 11,9 E)6 January 2005 Temperature and PSCs thresholds FLASH-B water vapour
FLASH-B water vapour observations in the presence of PSCs Ny-Alesund (78,9 N, 11,9 E)26 January 2005 lidar water vapour