Release of CALIPSO V4-10 Level-1 and Level-2 Lidar products
November 2016
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 the French AERIS/ICARE Data and Services Center in Lille, France. The new data products consist of the following:

Version 4.10 Lidar Level-1 Products
  • CAL_LID_L1-Standard-V4-10
Version 4.10 Lidar Level-2 Products
  • CAL_LID_L2_01kmCLay-Standard-V4-10
  • CAL_LID_L2_333mMLay-Standard-V4-10
  • CAL_LID_L2_05kmMLay-Standard-V4-10
  • CAL_LID_L2_05kmALay-Standard-V4-10
  • CAL_LID_L2_05kmCLay-Standard-V4-10
  • CAL_LID_L2_05kmAPro-Standard-V4-10
  • CAL_LID_L2_05kmCPro-Standard-V4-10
  • CAL_LID_L2_VFM-Standard-V4-10

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 The GTOPO30 Digital Elevation Model (DEM) used in V4.00 has been replaced by a substantially more accurate DEM developed by the CloudSat project.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 each data center through the following links:



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