CloudNet: TARA status and database

1
CloudNetTARA status and database

• H. Russchenberg , O. Krasnov Delft University of
  Technology IRCTR, The Netherlands

2
TARA current status

• It is working
• Starting August 18, 2004

1 hour
1 hour
1 min
1 min
1 min
RAW data 1 ms sweeps
0.512 sec moments of Doppler spectrum Z, V,
WCalibrated, net CDF format
Range resolution 30 m Doppler velocity 22
m/sec
CLOUDNET product 30 sec averaged Z,V,W
dataafter application cloud mask
3
3D wind mode for TARA
B0 - Fullpolarimetrybeam
November - December 2004, first experimental
campaign
B1 - One polarizationbeam
15
5 x 1-msec sweeps sequence B0HH B0HV B0VV
B1 B2 repeats N times to formDoppler spectra
in all channels
15
B2 - One polarizationbeam

• Output
• Standard products as it is now
• 3D wind field
• Polarimetric information

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TARA database status
2002
2003
2004
2005
January
January
31
February
February
4...
March
March

April
April

May
May

June
June

July
July

August
August

September
25
September

October
3
October

November
27
November

December

Total
298
Total
34(?)
On KNMI CloudNet FTP server
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LWC retrievals using radar - lidar algorithm

• NetCDF
• YYYYMMDD_site_LWC_Radar_lidar_method.nc
• Common variables - time, height, latitude,
  longitude, altitude, radar frequency, global
  attributes.
• 2D arrays
• optical extinction,
• radar reflectivity to optical extinction ratio
• Time series of lidars optical depth
• Retrievals
• Used for retrieval Z/? and Z thresholds,
• 2D liquid water categorization map and LWC array,
• time series of retrieved LWP (for the different
  Z-LWC relations)

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• liquid_water_map_bits
• Bit 0 - Reading's categorization product
  recognized pixel as water ((small droplets OR
  water precipitation) AND Temperature gt 0C)
• Bit 1 - radar signal presented
• Bit 2 - lidar signal (extinction) presented
• Bit 3 - radar reflectivity to lidar extinction
  presented
• Bit 4 - atmospheric water, class 1 - "water cloud
  without drizzle"
• Bit 5 - atmospheric water, class 2 - "water cloud
  with light drizzle"
• Bit 6 - atmospheric water, class 3 - "water cloud
  with heavy drizzle"

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May 19, 2003, Cabauw
8
May 19, 2003, Cabauw
9
May 19, 2003, Cabauw
10
May 19, 2003, Cabauw