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TTO1c ( previous task team for wind profilers ) (Saïd-Campistron-Sokolov). Data processing and data providing to the data bank Scientific concerns : - water vapor content profiles (Saïd) - VHF network (Campistron) - Pianottoli UHF (Sokolov) - UHF network (Saïd).
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TTO1c (previoustask team for windprofilers) (Saïd-Campistron-Sokolov) • Data processing and data providing to the data bank • Scientificconcerns : • - water vapor content profiles (Saïd) • - VHF network (Campistron) • - Pianottoli UHF (Sokolov) • - UHF network (Saïd)
DATA PROCESSING • High mode, processed and sent to the data-bank for SOP1 + monthly and IOP’s quick-looks. • No bird-filtering: 5 French UHFs + 3 VHFs. ExceptOct 15-Nov 5 in Pianottoli. SpanishUHFs and miniVHFrequirespecific computation. Will not beprovidedthrough the DB. • High mode, bird-filtered. Provided for AROME assimilation. Will be sent to the DB in earlyJune (1 file/30 min/radar) • Low mode : some issues in Pianottoli: the (new) radar revealed not to bepowerfulenough (limited range : 1-1;5 km, outsiderainyepisods). • EOP data untildec 2013: not sent to the DB yet but most data sets have been recovered . 3 VHFs have been totallyprocessed (13 months), Marignane and Perpignan (on goingprocessing). • Expected end of processing : september
WATER VAPOR CONTENT Nothingdonesince Cassis (poster presentation) Needsfurtherwork to know whyitsometimesperfectlyworks and sometimes not. One Coreancolleague, presently in ourlab, tried the method on Coreanwindprofilers: same conclusions up to now. The methodis not autonomous: requiresadditionnalparameters . The aimis to improve the time resolutionretrieving of the humidity profiles, using for instance radiosounding profiles at a poor time resolution.
Analysis of the semidiurnal atmospheric tide based on the observations of a three VHF wind profiler synoptic network B. Campistron1, F. Saïd1, and K.E. Kim2 14th International Workshop on Technical and Scientific Aspects of MST Radar. May 25 - 31 , 2014 - INPE - São José dos Campos/SP – Brazil A network of VHF windprofilersisvery efficient to extractfrom the windfield and accuratelyretrieve the tiny signature of the thermal atmospherictidesfrom 2 km up to 15 km altitude. The oscillation in the lowstratosphere of upward and downward motions, each lasting six hours, canmodulate the generation or dissipation of upperclouds and socanmodify the radiative global atmospheric budget. Fig. 10. Time-height composite day for the semidiurnal tide at the network centroid of the horizontal pressure gradient
PIANOTTOLI UHF in CORSICA A. Sokolov is presently improving the statistical method he presented in Cassis. His multi-scale technique based on spatial and temporal correlations helps him to define regions and scales influenced or not by local meteorology. He would like a larger dataset at Pianottoli than had been initially provided, and is waiting for additional processed data. He expects to enlarge his studies using data at other locations (Candillargues, Levant, Marignane, Perpignan).
14th Workshop on Technical and Scientific Aspects of MST Radar (MST14/iMST1), Sao José dos Campos, May 25-31 2014 Wind field conditions in the north-western Mediterranean basin monitored by a network of wind profiler radars. F. Saïd* (1), B. Campistron (1), D. Lambert (1), H. Delbarre (2), M. Abadie (1), J.A. Aranda (3) , E. Bargain (1), F. Besson (4), Y. Bezombes (1), J.L. Boichard (5), J.L. Bourrian (6), O. Bousquet (7), G. Canut (7), G. Cherel (7), S. Derrien (1), A. Doerenbecher (7), J.M. Donier (7), T. Douffet (7), P. Durand (1), J.B. Estrampes (1), A. Ezcurra (8), A. Frappier (7), J.A. Garcia-Moya (9) , O. Garrouste (7), J.A. Guijarro (10), R. Guillot (7), C. Hervier (11), J.L. Jouve (4), J. Lovichi (12), M. Macaigne (1), M. M. Maruri (3)(8), B. Piguet(7), E. Pique (1), Y. Pointin (11), S. Prieur (1), E. Richard (1), C. Ruffin-Soler (2), A. Sokolov (2), D. Subra (7), J. Torres (3) and M. Turp (13)
Assumingthatspace and time variations are linear, at the scale of the networks, weretrieve U, V, and W components of the wind, at time ti and location (xi,yi,zi) using: • f(ti+dt; xi+dx; yi+dy; zi+dz) = f(ti; xi; yi; zi)+ ∂f/ ∂t dt + ∂f/ ∂x dx + ∂f/ ∂y dy + ∂f/ ∂z dz. • The choice of dT and dZisvery important sincetheseparameters control the time and spaceresolution and help filtering local disturbances or spurious data. • HeredT=3h and dZ=500m • Validation donewith • Aircraft data on horizontal, stabilized legs • Constant volume balloons for the lowlayers (trajectories or back trajectories)
More deceivingresultsatlowleveleven if the trajectories (or back trajectories) canbeconsidered as the strictest test sinceitaccumulates the discrepanciesduringhours (here : 11h for the 2nd fig.). Question: willitbe the sameduring IOP 2, when the winds are faster and are blowing offshore?
PRELIMINARY STUDY OF IOP13: 14-16 October 2012: HPE’s on Corsica and northernItaly On Oct. 14 a moderate cold front, associated with a trough, is extending from Algeria to Corsica and northern Italy, and shifts towards southeastern Italy. Warm, moist, unstable air is advected across the Golfe du Lion, impinges the Corsica island during the Oct. 15 night and northern Italy on Oct. 16 morning. Fig. 6 :. Geopotential at 500 hPa on a) Oct 14, 18:00UTC, b) Oct 15, 0.00UTC (with wind above 10m/s at 300hPa) and c) Oct 15, 12h from the ARPEGE (from the HYMEX website: http://sop.hymex.org).
0ct 14- 18.00UTC 0ct 14- 13.00UTC 0ct 14- 15.45UTC Southern pattern twists and lines up with the easternSpanishmountains Pattern slowly shifts to the East (cyclonic motion, not shownhere) Radar echoes on mountainridges 0ct 14- 19.00UTC 0ct 14- 20.15UTC 0ct 14- 22.00UTC … and slowly moves to the East, withsomecellsgrowingahead the front line, fed by the conditionnallyunstable and moistened air over the sea 0ct 15- 00.00UTC 0ct 15- 02.00UTC 0ct 15- 06.00UTC Violent storm in Corsica. The backside of the front line is no more in the radar range The eastenercellsreachCorsica
Comparison of the R2 network windfieldsat 3500m against the MesoNH- 2.5 km windfields: somedifferenciesbetweenbothwindfields but the shift of the cyclone to the East and the strengthening of the windvelocityisobvious on bothfields.
Meanbiasbetweenbothfieldsduring 24h hours: the MNH variability for U and V quantified by the RMS isshownwiththinlinesalongbiases for U, V and the windvelocity. The nearly constant phase shift between U and V denotesdiscrepancies in the vorticitywindfield, thatcouldbeeasilychecked .
Plenty of otherthings to do: • Better analyse the dynamicalevolution and try to explain the bias • Check with the other observations (radars, MSF images, surface rainfall …) • Analyse horizontal divergence and vertical vorticityevolutions in the mid-troposphere • Look at back trajectories • Check the conditions athigherlevelwith the VHF network (which shows some tropopause foldingduring the period) • Write a paper on the profiler network… 4.5 km 3.5 km 2.5 km