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Record Search Query: ServiceParameters>DATA MANAGEMENT/DATA HANDLING>CATALOGING

CALIPSO Data Read Software
Entry ID: LARC_calipso_read_software_routines
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Summary
Abstract: Introduction:

The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite will provide new insight into the role that clouds and atmospheric aerosols play in regulating Earth’s weather, climate and air quality. In order to do this, a wide variety of scientific data products will be available to the science community. These products will be derived from the data acquired from three on-board instruments; the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), the Wide Field Camera (WFC) and the Imaging Infrared Radiometer (IIR). These data products are described in the CALIPSO Data Products Catalog (DPC) currently available on the CALIPSO public web site at URL: http://www-calipso.larc.nasa.gov/resources/project_documentation.php. The Langley Research Center (LaRC) Atmospheric Science Data Center (ASDC) processes, archives, and disseminates the CALIPSO data products. The web site address for the ASDC is: http://eosweb.larc.nasa.gov/. These data products are output using the Hierarchical Data Format (HDF).

Readers

A set of basic CALIPSO data product readers has been developed to aid users in their ability to read the HDF formatted files. This set of readers is written using the Interactive Data Language (IDL) available through ITT Visual Information Systems at URL: http://www.ittvis.com/ and go hand in hand with either the CALIPSO Data Products Catalog (DPC) Release 3.4 or the CALIPSO DPC Release 2.4. A list of the major data products, their associated readers, commons, check programs, and the corresponding DPC Table numbers are contained in the tables below.

Due to the nature of the HDF formatting and the need to assign each parameter to the appropriately named variable, there must be an exact match between variable names stored in the file and the command parameter used to retrieve that variable. These readers are written to provide users with the greatest flexibility to select only those parameters that are necessary for their applications. They were not written for efficiency as much as simplicity. There is a one-line call for each parameter, that can be commented out by placing a ‘;’ at the beginning of the line. Already commented out in each program, but left available for the users, are print statements that will provide more detailed information about each parameter contained in the HDF file. Each reader takes as input two quoted string parameters, PATH and FILE NAME. The PATH name contains the directory path to the folder that contains the data, and the FILE NAME contains the full name of the file to be read.

The commons associated with each data product reader contain abbreviated names for each parameter. If the user chooses not to read every data product, these variables will not be filled, but will not present any problems if left in the common. Of course, the user may change these names to match the desired names for their application, but care should be taken to ensure that names are changed in the IDL code as well as the associated common. In some cases, single dimension arrays are read as two dimensional with the initial dimension being set to 1. This does not affect the data in any way, but may need to be considered later when working with the arrays. In order to correct this issue, a simple call to the IDL REFORM function will adjust the array to a single dimension. For example, ArrayA is created with dimensions of (1,50). Issuing the command ArrayA = REFORM(ArrayA, /OVERWRITE) returns ArrayA with a single dimension of (50), and the actual data remains unchanged.

Simple check programs are also provided for each of the readers. These check programs are called at the end of each reader program, and are a double check to ensure that all variables are filled. The calls to the check programs can be commented out once the user is certain that all parameters of interest are read correctly. The check programs issue a ‘HELP, Variable’ for each of the common variables. The HELP command provides common, format, dimension and static value information for all variables. The output from the HELP command is sent to STDOUT, unless otherwise redirected.

[Summary provided by the Langley Research Center Distributed Active Archive Center.]

Related URL
Link: GET SERVICE > GET SOFTWARE PACKAGE
Link: GET SERVICE > GET SOFTWARE PACKAGE
Description: Download CALIPSO Data Read Software.

Link: VIEW RELATED INFORMATION
Description: CALIPSO Data Read Software documentation.
Service Citation
Title: CALIPSO Data Read Software
Provider: NASA Langley ASDC
URL: http://eosweb.larc.nasa.gov/PRODOCS/calipso/Tools/read_software_rou...
Access Constraints
None
Service Provider
Atmospheric Science Data Center, Science Directorate, Langley Research Center, NASA

Service Provider Personnel
Name: ASDC USER SERVICES
Phone: 757-864-8656
Email: support-asdc at earthdata.nasa.gov
Contact Address:
NASA Langley Atmospheric Science Data Center
User and Data Services
NASA Langley Research Center
Mail Stop 157D
City: Hampton
Province or State: VA
Postal Code: 23681-2199
Country: USA
Distribution Media
Distribution_Media: Online
Distribution_Size: 410 KB
Fees: No fees

Distribution_Media: Online
Distribution_Size: 169 KB
Fees: No fees
Personnel
ASDC USER SERVICES
Role: TECHNICAL CONTACT
Phone: 757-864-8656
Email: support-asdc at earthdata.nasa.gov
Contact Address:
NASA Langley Atmospheric Science Data Center
User and Data Services
NASA Langley Research Center
Mail Stop 157D
City: Hampton
Province or State: VA
Postal Code: 23681-2199
Country: USA

TYLER B. STEVENS
Role: SERF AUTHOR
Phone: (301) 614-6898
Fax: 301-614-5268
Email: Tyler.B.Stevens at nasa.gov
Contact Address:
NASA Goddard Space Flight Center
Global Change Master Directory
City: Greenbelt
Province or State: MD
Postal Code: 20771
Country: USA
Creation and Review Dates
SERF Creation Date: 2012-06-14
SERF Last Revision Date: 2012-06-15
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