Prsentation PowerPoint

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SIRTASite Instrumentalde Recherche
parTélédétection Atmosphérique
Martial Haeffelin SIRTA Coordinator CLOUDNET
Meeting, Paris May 2002
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SIRTA dedicated to cloud observation
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SIRTA Cloud-Aerosol Lidar

• Nd-Yag laser (w 1064 nm, 2w 532 nm)
• 200 mJ (100 for 2w) 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
Lidar backscattering coefficient
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Operations of Cloud-Aerosol Lidar
Goal reach 100 on 4-day schedule starting Sept
2002
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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

Radar reflectivity
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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

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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
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10.6mm 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 mm)
• 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
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Microwave Radiometers
Column integrated measurements of water vapor and
liquid vapor in the atmosphere
Frequencies 23.8 and 31.7 GHz DRAKKAR nadir
pointing radiometer RESCOM scanning
radiometer Beam width DRAK 11-13o RESC 2o
RESC Calibrated by tip-curve technique DRAK
Calibrated w/ resp. to RESC
Continuous observation
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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