CALIPSO Status

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CALIPSO Status
Carl Weimer - Ball Aerospace Technologies Corp.
Mike Cisewski, Yongxiang Hu, Bill Hunt, Chip
Trepte, Dave Winker NASA LaRC Floyd Hovis -
Fibertek Corp.
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CALIPSO Introduction

• CALIPSO Satellite
• Proteus Spacecraft from (CNES/Alcatel)
• Payload (NASA/CNES/Ball Aerospace)
• CALIPSO Payload Instruments
• Wide Field Camera Cloud Camera matched to MODIS
  (645 nm, 125 m pixel)
• Infrared Imaging Radiometer Three band Thermal
  Images (8.65, 10.6, 12.05 µm)
• CALIOP Rayleigh-Mie Lidar (laser radar) for
  clouds and aerosols
• CALIOP
• Two Wavelengths (532 nm and 1064 nm)
• Polarization sensitive at 532 nm (Photomultiplier
  Detectors aligned Parallel and Perpendicular to
  laser linear polarization) Polarization
  Accuracy 0.5
• Polarization insensitive at 1064 nm (single
  Avalanche Photodiode detector)
• Sensitive to single photons at 532 nm, less
  sensitive at 1064 nm
• Dynamic range 8 million
• Vertical Resolution 30 m fixed by
  Analog-to-Converter clock (increases in steps to
  300 m in stratosphere)
• Data collected for altitudes -2 km to 40 km
• Laser Footprint on ground 70 m, geolocated to
  better than 60m
• Laser pulse emitted at 20 Hz repetition (330 m
  spacing between laser pulses)

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CALIPSO Satellite Payload
Lidar Receiver Telescope
Star Tracker Assembly
Wide Field Camera
Imaging Infrared Radiometer
Integrated Lidar Transmitter
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Lidar Core Transmitter and Receiver
Etalon Filter
Adjustable Boresight Mechanism
APD
PMTs
Laser Radiator
Optical Bench
Laser Optics Modules - Fibertek
Telescope 1 meter Beryllium
Beam Expander Optics
ILT (Integrated Lidar Transmitter)
ILR (Integrated Lidar Receiver)
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CALIPSO Laser StatusAlways the First Questioned
Asked

• Completed One Billion Laser Shots On-Orbit Feb
  3!
• Only have operated one laser, second laser held
  in reserve.

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CALIPSO Summary

• Satellite and Payload are healthy, data trends
  are all acceptable to meet full mission
  requirements
• Mission complete in May 2009, Mission extension
  will be applied for in January 2009
• Single String Satellite and many new
  technologies as part of this Pathfinder mission
  requires careful risk management throughout
  program life.
• Level 2 Science Data now being released (see
  http//www-calipso.larc.nasa.gov/products/)
• Includes extinction for the first time
• See Dave Winkers Working Group presentation from
  Feb 2007 for examples of aerosol and cloud
  science data.
• Validation and Calibration work is ongoing
• New Data Products and capabilities are being
  developed
• Now providing an Expedited Data set for Science
  Campaigns
• Working to decrease data latency to support
  weather and air quality users.
• New Products include ocean subsurface and
  altimetry demonstrations (Yong Hu)

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One New Application of CALIPSO - Ocean Windspeed

• The Cox-Munk Equation relates ocean wind speed to
  surface reflectivity
• Was applied previously to LITE space-based lidar
  data by Menzies, Tratt, and Hunt
• Yong has submitted a paper showing global
  comparison of passive microwave system AMSR-E on
  Aqua to CALIPSO measured Ocean Windspeed
• Preliminary results show agreement is better than
  1.3 m/s rms using single laser shots
• Trades
• Microwave systems give superior all-weather
  performance
• CALIPSO measures over much smaller footprint (70
  m vs. 20 km)
• CALIPSO is calibrated using reflectivity from
  upper atmosphere
• Working towards using ocean surface as an
  independent lidar calibration and also as
  independent check on column aerosol extinction.

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AMSR-E Winds vs CALIPSO Winds
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Global Comparison Between CALIPSO and AMSR-E
(AQUA) Wind speeds
Residual Windspeed Error for CALIPSO arises from
aerosol loss. Possible instrument effects being
studied.