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The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO)

CALIPSO, a joint mission between NASA and the French space agency, CNES, provides new insight into the role that clouds and atmospheric aerosols (airborne particles) play in regulating Earth's weather, climate, and air quality.

CALIPSO - Lidar Levels 1 and 2 Version 4.10 Data Available

The CALIPSO mission announces the release of new versions of its standard Level 1 and Level 2 lidar data products. These products are available through the Atmospheric Science Data Center (ASDC) at NASA Langley Research Center and include the following:
Version 4.10 Lidar Level 1 Products

Version 4.10 Lidar Level 2 Products

The V4.10 CALIOP Level 2 data products are the first major revision to the Level 2 product suite since May 2010. The extensive improvements made in this new release correct numerous artifacts and significantly enhance the content and quality of the science data. In addition to the substantial updates made to all existing Level 2 products, V4.10 introduces a new merged layer product that reports the spatial and optical properties of cloud and aerosol layers in a single file.

The data processing algorithms and code used to generate the updated V4.10 CALIOP Level 1 data product are unchanged from V4.00. The only differences between the two versions are the essential ancillary data sets. The GTOPO30 Digital Elevation Model (DEM) used in V4.00 has been replaced by a substantially more accurate DEM developed by the CloudSat project. Likewise, the Global Modeling and Assimilation Office (GMAO) Forward Processing for Instrument Team (FP-IT) meteorological forecast product has been replaced with the higher quality Modern Era Retrospective-Analysis for Research (MERRA-2) reanalysis product. Use of the MERRA-2 data has been shown to yield more accurate and reliable CALIOP calibration coefficients.

The version 3.x (3.01, 3.02 and 3.30) CALIOP Level 1 and Level 2 data products will continue to be generated and made publically available, with version 4.10 running in parallel. Unlike version 3.x, which is released continuously following 2-3 day latency from downlink, new releases of the version 4.10 Level 1 and Level 2 product will have a latency of several weeks. This change in latency is a direct response to now using the MERRA-2 meteorological data. Generation and distribution of the standard version 3.x will continue until release of an updated version of the IIR Level 2 product, at which point the standard will no longer be supported. Expedited and quick-look datasets, which continue to rely on the GMAO FP-IT, will remain at version 3.x.

The product is available beginning with data from June 13, 2006 (following CALIOP first light), and as of this announcement, through December 31, 2008. Remaining data will be available as it is produced.

Information about the data products including data availability, user documentation and quality statements, relevant links, sample read software, and tools for working with the data, etc. can be found at the following ASDC links:

In-depth overviews for the products can be found in the following CALIPSO link to the data quality summaries:


The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite provides new insight into the role that clouds and atmospheric aerosols (airborne particles) play in regulating Earth's weather, climate, and air quality.

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. CALIPSO was launched on April 28, 2006 with the cloud profiling radar system on the CloudSat satellite.

CALIPSO and CloudSat are highly complementary and together provide new, never-before-seen 3-D perspectives of how clouds and aerosols form, evolve, and affect weather and climate. CALIPSO and CloudSat fly in formation with three other satellites in the A-train constellation to enable an even greater understanding of our climate system from the broad array of sensors on these other spacecraft.

CALIPSO is a joint U.S. (NASA) and French (Centre National d'Etudes Spatiales/CNES) satellite mission that has been in operation for four years.  » Read more …


» CALIPSO’s Data Availability Tool
» CALIPSO’s Search and Subsetting Web Application

Last Updated: June 29, 2016
Curator: Charles R. Trepte
NASA Official: Charles R. Trepte

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