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