Cloud-Aerosol Transport System

Level 0

Reconstructed, unprocessed instrument data at raw resolutions (i.e. the downlinked raw photon counts from the CATS instrument). Any and all communications artifacts (e.g. synchronization of packets, communications headers, duplicate or missing data) are removed in the L0 process.

Level 1A

L0 data that is time-referenced, geo-located, corrected for detector nonlinearity and instrument artifacts, normalized to laser energy, and annotated with ancillary information. The CATS L1A data (relative normalized backscatter) is an internal product only and is not disitributed.

Level 1B

L1A data that have been calibrated, annotated with ancillary meteorological data, and processed to sesor units. The CATS L1B data (attenuated total backscatter and depolarization ratio) is archived as Level 1 data.

Level 2

Operational Level 2

L1B files that are run through the new operational CATS L2 algorithm, which will include new capabilities. Geophysical parameters, such as the vertical feature mask, profiles of cloud and aerosol properties (i.e. extinction, particle backscatter), and layer-integrated parameters (i.e. lidar ratio, optical depth). The Operational L2 data files will be available on this site.

Heritage Level 2

Same parameters as above, but these are produced using the CALIPSO L2 algorithm. This L2 output will be available at the Langley DAAC.

Read more about data processing levels.

CATS Products and Data Ordering

CATS produces Level 1 and Level 2 science data products that are listed in detail in the CATS Data Products Catalog. These products are archived and distributed by the Atmospheric Science Data Center. For more information on CATS data products, please see the CATS Algorithm Theoretical Basis Document. Notes for the current data product release can be found here.

CATS Data Policy

Access to CATS data is not restricted. However, we do ask that data users respect the experiment PIs and others with rights to the data. An offer of co-authorship on any publications, presentation, etc., should be made to the PI and his/her team if images and/or data are used (even if they are freely accessed).