Join NASA’s Students’ Cloud Observations On-Line (S’COOL) Project in the CALIPSO Intensive Observation Campaign

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NASA Scientist on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) Mission are turning to S’COOL participants for help! The CALIPSO Team would like to compare CALIPSO satellite data and ground cloud observations to better understand the roles clouds and aerosols play in regulating Earth’s weather (depending on their properties some aerosols reflect sunlight, cooling the atmosphere, while others absorb sunlight, warming the atmosphere), but they need more ground observations that match to CALIPSO data.


CALIPSO in the A-Train,  “curtain” of data collected


CALIPSO’s Green Laser, pulsing 20 times per second








CALIPSO uses a lidar and imaging system to collect data, pulsing a laser through the atmosphere, measuring the reflected light, or backscatter, off of the particles in the atmosphere.  This process returns a “curtain” of data or information on a slice of the atmosphere, covering a narrow footprint on the Earth’s surface, but collecting data 30km high into the atmosphere. CALIPSO travels in line with a team of satellites called the A-Train.  This allows near-simultaneous observations of a wide variety of parameters to aid the scientific community in advancing our knowledge of Earth-system science and applying this knowledge for the benefit of society.

For accuracy and validation purposes each satellite aims to stay within a certain range of a designated orbit path, this range is called the Control Box.  For CALIPSO, the control box is 10km on either side of the designated orbit path (20km wide swath). Due to the effects of drag and maneuvers to keep CLAIPSO at the optimal flying altitude, the satellite drifts from side to side of this 20km swath or Control Box. To incorporate CALIPSO into the S’COOL project the S’COOL team narrows the overpass path even more, to schools within 10km on either side of the CALIPSO overpass, to improve ground observation matching possibilities.  Based on these facts, ground observers/sites at locations within the larger Control Box , or predicted overpass, may not always get an overpass in reality due to the movement of the satellite, and/or the narrowed S’COOL overpass area.

CALIPSO3Based on the predicted orbit of CALIPSO, the S’COOL team is asking participants located under it’s path to make S’COOL observations when the satellite passes over, as often as possible, even during night time overpasses.  To participate in the CALIPSO Intensive Observation Campaign, observers will follow the same S’COOL process, matching to the CALIPSO Satellite:

  1. Obtain satellite overpass times for CLAIPSO, remember not all observation locations in the predicted path will have a CALIPSO overpass close enough to make a match.
  2. Observe the sky within 15 minutes of your CALIPSO overpass time.
  3. Report your observation data to the NASA Team.

Sample match email, orange circle indicates CALIPSO tutorial link

If CALIPSO data matches a ground report, the participant will receive a “match” email with their ground observation aligned with the satellite data.  A thumbnail image will be available to review the CALIPSO match. A CALIPSO tutorial is also available directly under the thumbnail image for tips and tricks on interpreting the data (Feature Mask). Participants can provide comparison comments and analysis of their match to help NASA scientist, contributing to satellite validation!

If you are not currently a S’COOL Observer and would like to join the CALIPSO Intensive Observation Campaign register your classroom: or start observing immediately:  Scientists are counting on your observations!

Thank you for contributing to a better understanding of the World around us! Keep an eye out; as we move through the CALIPSO Intensive Observation Campaign we will be sharing what NASA Scientists discover.

The S’COOL Team

 NASA Langley Research Center, Science Directorate

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