Upload
loren-parsons
View
217
Download
2
Embed Size (px)
Citation preview
SIRTASite Instrumentalde Recherche parTélédétection Atmosphérique
Martial HaeffelinSIRTA Coordinator
CLOUDNET Meeting, Paris May 2002
LIDAR Backscattering Lidar (532 w/ polar., 607, 1064 nm) Clouds, aerosols (100m-20km) 1993
Scanning Coherent Doppler Lidar (10.6m) 3D wind fields 1999
Backscattering Lidar (316 nm) Ozone, aerosols 1999
Raman Lidar (355 nm) Water vapor profile 2002
RADAR Doppler Radar (94 GHz), dev. of polarization 2002 Clouds 2001
Doppler Radar (5 GHz) Precipitation, 3D wind 1999
RADIO-METER
Pyranometer pyrgeometer dev. BSRN station 2002 Radiative fluxes 1993
AERONET Sun-Photometer (8 channels) Aerosol properties, water vapor content 1999
Infrared imager (ground version of CALIPSO) Brightness temperature 2002
Scanning micro-wave radiometer (23.8 + 31.7 GHz) Water content (liquid + vapor) 1999
IN-SITU Weather station Pressure, Temperature, Humidity (PTH) 1996
Radio-sondes from Météo-France (15km from site) PTH vertical profile 1999
Sonic anemometer Turbulent fluxes 2002
Spectro-pluviometer Drop radius + velocity 1999
SIRTA: dedicated to cloud observation
Lidar backscattering coefficient
SIRTA Cloud-Aerosol Lidar
• Nd-Yag laser ( 1064 nm, 2 532 nm) • 200 mJ (100 for 2) per pulse at 20 Hz• Detection :
• 532 nm // and • 607 nm N2 Raman• 1064 nm
• NFOV telescope: 3-20 km• WFOV telescope: 100m - 4 km
9 GHz radar for airplane detection
Aug-Dec 2001 Jan-May 2002
Days of operation / month 8.4 11.4Inclement weather/month (on days of operation)
2.2 1.6
Maintenance 2.0 2.0Rate of success for 2-day schedule (Mon, Thu)
>100% >100%
Rate of success for 4-day schedule (Mon-Thu)
60% 75%
Operations of Cloud-Aerosol Lidar
Goal: reach 100% on 4-day schedule starting Sept 2002
Radar reflectivity
RASTA Cloud Radar
• Transmitter: • Frequency: 95 GHz • Peak power: 1.8 kW
• Antenna: (vertically pointing)• 1.2 m diameter, 0.2o beamwidth • Sensitivity: -50 dBZ at 1 km• Range: 200-15 km
Operations of RASTA Cloud Radar
•Ground version ready in Sept 2001
• Failure after a few tests due to problems in the high-voltage components of the Klystron transmitter
• Transmitter sent back to manufacturer in Sept 2001
• Due back June 2002
• July-Aug 2002: tests + 2 days/week operational observations
• Goal: reach 100% on 4-day schedule starting Sept 2002
5 GHz Doppler Radar
C-band pulsed radar designed to study dynamic and microphysical properties of precipitating and non-precipitating
systems in the troposphere
•Transmitter:•Frequency : 5.5 GHz•Peak power : 250 kW
•Antenna:•Diameter : 4 m•Gain : 44 dBZ at 1 km•Azim. + Elev. scanning
•Dual polarization (emission/detection)•Range: 100 km; Resolution: 200 m
Goal: Operations during IOPs to provide multi-frequency data and cloud advection data
10.6m Doppler Lidar
IR Doppler Lidar designed to get 3-D wind profiles in the troposphere and to study turbulence in the boundary layer
• Pulsed TE-CO2 laser (10.59 m) • 150-300 mJ per pulse at 2 Hz• 2-mirror scanning system• Range : 10 km, Resolution: 450 m
Goal: Operations during IOPs to provide cloud advection data
DRAKKARMicro-wave Radiometer RESCOM Scanning
Micro-wave Radiometer
Microwave Radiometers
Column integrated measurements of water vapor and liquid vapor in the atmosphere
Frequencies: 23.8 and 31.7 GHzDRAKKAR: nadir pointing radiometerRESCOM: scanning radiometerBeam width : DRAK 11-13o; RESC 2o
RESC: Calibrated by tip-curve techniqueDRAK: Calibrated w/ resp. to RESC
Continuous observation
Data Archival, Visualisation and Dissemination
• Archived data are progressively converted into NetCDF format• Data sorted by instrument (or group) and data level• Automatic quick-look image production under development:
• real-time QL for current day• archived QL available for browsing and ordering
• Archived data available for ordering through web site:• Data users register with simple login name• Data ordering form allows users to select:
• Time range• Instrument data / QL• Data levels
• Ordered files are provided on ftp site• SIRTA general website is being redesigned