An Introduction to CALIPSO with thanks to Stuart Young of CMAR

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An Introduction to CALIPSO(with thanks to Stuart
Young of CMAR)

• CALIPSO (Cloud-Aerosol Lidar and Infrared
  Pathfinder Satellite Observation) flies in tandem
  with CloudSat and three other satellites (the
  A-train) launched April 2006
• CALIPSO combines an active lidar instrument with
  passive infrared and visible imagers to probe the
  vertical structure and properties of thin clouds
  and aerosols over the globe.
• Advantages compared to CloudSat CALIPSO is more
  sensitive, has finer vertical resolution, has a
  smaller footprint leading to less confusion and
  cloud contamination, detects both clouds and
  aerosols right down to the surface (if not
  attenuated) while CloudSat has issues below about
  1000m.
• But CloudSat is better in dense and deep water
  clouds where the stronger scattering at optical
  wavelengths leads to complete attenuation of the
  CALIPSO signal before the cloud base is reached.

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Some potential projects using CALIPSO data in the
Australian region

• Comparison with NWP Model Clouds
• Save NWP outputs of cloud type and location along
  CALIPSO orbit tracks for comparison with CALIPSO
  Vertical Feature Mask (VFM) clouds.
• Comparison with AAQFS Model Aerosols
• Save AAQFS outputs of aerosol type and location
  along CALIPSO orbit tracks for comparison with
  CALIPSO Vertical Feature Mask aerosols (in
  progress)
• Comparison with Climate Model Cloud Statistics
• Compare cloud climatology of type height
  distribution from model with analyses of CALIPSO
  VFM data for year. (Have already analysed June 06
  May 07)
• Development of Australian Aerosol Climatology
  for inclusion in Climate Model
• Seasonal variation of type, location, AOT,
  mixing depth etc.

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CALIPSO 16-day orbit tracks
kathleen.a.powell_at_nasa.gov
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532-nm attenuated backscatter
CALIPSO augments MODIS - aerosol profiles
- identifies heterogeneous columns -
aerosols beneath thin cirrus, in
broken cloud fields, in sunglint - and at
night!
Depolarization ratio
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1064-nm attenuated backscatter
Ratio of backscatters at 1064 and 532 nm
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AAQFS Validation Project Results (in progress)
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July 2006
Detection Frequency of Opaque Clouds
Detection Frequency of Clear Profiles
Number of passes
High Cloud Frequency
Low Cloud Frequency
Mid-level Cloud Frequency
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Cloud Top Heights
Dec 06 Feb 07
June August 06
Magenta tropical clouds Blue temperate clouds
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Level 2 data products for clouds (on the way)
Data Product Resolution Horizontal Vertical