CERES EBAF Readme File 1.0 Introduction This readme file document provides information on the following Clouds and Earth's Radiant Energy System (CERES) EBAF data set: CERES_EBAF_Edition4.1 This document includes the following sections: Section 2.0 - Data Set Description Section 3.0 - Format and Packaging Section 4.0 - Science Parameters Information Section 5.0 - Description of Sample Read Software Section 6.0 - Implementing Sample Read Software Section 7.0 - Sample Output Section 8.0 - Additional Data Information (This section is optional) If users have questions, please contact the Langley ASDC User and Data Services Office at: Atmospheric Science Data Center User and Data Services Office Mail Stop 157D NASA Langley Research Center Hampton, Virginia 23681-2199 U.S.A. E-mail: support-asdc@earthdata.nasa.gov Phone: (757)864-8656 URL: https://eosweb.larc.nasa.gov 2.0 Data Set Description 2.1 Instrumentation Description For a complete description of the CERES experiment and instruments, please refer to the documentation provided at the URL http://ceres.larc.nasa.gov. 2.2 Data Quality For a discussion regarding the quality of the EBAF data set, please refer to the corresponding Quality Summary Document available from the URL https://eosweb.larc.nasa.gov/project/ceres/quality_summaries/CERES_EBAF_Ed4.1_DQS.pdf 2.3 Science Representatives *NOTE TO USER: If you have any questions concerning the sample code or the data, please contact the Atmospheric Sciences Data Center User Services Office. The contact information is provided above in Section 1.0. 1. Dr. Norman G. Loeb, CERES Interdisciplinary Principal Investigator NASA Langley Research Center Mail Stop 420 Hampton, VA 23681-2199 E-mail: Norman.G.Loeb@nasa.gov FAX: (757)864-7996 Phone: (757)864-5688 3.0 Format and Packaging This package includes a program, written in Fortran, which will read the EBAF netCDF file. There is example output code provided in the main (read_ceres_ebaf.f90) program. This read program is provided as a template to the user who will need to modify it to output or otherwise handle various EBAF parameters. Information on the structure of the EBAF file can be found by executing a dump of the netCDF file (see Section 3.3 below). 3.1 Sample Read Package Contents This package consists of the following files: 1) read_ceres_ebaf.f90 2) sample_output_ebaf.txt Descriptions for each file is as follows: 1)'read_ceres_ebaf.f90' is the main program which provides information about all of the parameters in the CERES EBAF netCDF file. At the end of the program, the user must make modifications in order to either print out or process the parameters they would like to use. 2)'sample_output_ebaf.txt' is an ASCII output file obtained from running the read_ceres_ebaf read program with the 'CERES_EBAF_Edition4.1_200003-201902.nc' file as input. This is provided so that the user can compile, run, and verify output of the read_ceres_ebaf program before making any modifications. 3.2 Zip Information To read the files, first unzip them with Info-Zip software. Information about downloading and using this freeware is available at the URL: http://www.info-zip.org/pub/infozip/Info-ZIP.html 3.3 Unix commands for netCDF Some Unix commands for handling netCDF at the command line are: ncdump -h - lists the header information for the file ncdump -v '' - lists the values for the variable name 3.4 netCDF library netCDF information, documentation, tutorials, libraries, etc. can be found on-line at the URL http://www.unidata.ucar.edu/software/netcdf/ 3.5 Data Format The EBAF data file is written in netCDF. 4.0 Science Parameters Information Execute the first ncdump command listed in Section 3.3 (Unix commands for netCDF) to get header information that includes the following for each parameter: Type (int, float, etc...) Name Dimensions long_name Units Ranges (minimum and maximum values) 5.0 Description of Sample Read Software The sample read software in this package is intended as a base that is to be modified. The sample software does read in all parameters in the file. A user may make modifications near the bottom of the code where the output is written. A note to the user: It is recommended that before modifying the EBAF read program, the user should first compile and run the EBAF read program and compare the results that are created by the read program with the list of values in the sample output file,'sample_output_ebaf.txt'. If this test is successful, then the user should modify the the EBAF read program or create their own software to handle the parameters in which they are interested. 6.0 Implementing Sample Read Software 6.1 Compiling the Sample Read Software 1. Place the 'read_ceres_ebaf.f90' read code and the EBAF data set in the same directory. 2. Compile the code with the following command: If you have the nc-config command available as part of your netcdf installation, use: gfortran `nc-config --fflags` read_ceres_ebaf.f90 `nc-config --flibs` -ldl -o read_ebaf OR if you would like to specify your netCDF include and library directories yourself, use: gfortran -I/your_include_dir read_ceres_ebaf.f90 -L/your_lib_dir -lyour_lib1 -lyour_lib2 -ldl -o read_ebaf Example: gfortran -g -O2 -I/usr/local/include read_ceres_ebaf.f90 -L/usr/local/lib -lnetcdf -lnetcdff -ldl -o read_ebaf 6.2 How to Run the Sample Read Software 1. Execute read_ebaf by typing at the command line: > read_ebaf 7.0 Sample Output The program runs and currently is coded to print out 24 lines (one for each of the first 24 months) in the file with the global means for surface net SW, net LW, and net total fluxes as a sample. Compare this output to the values in sample_output_ebaf.txt, which is also included below. Global Mean Surface SW Net Surface LW Net Surface Total Net All-sky 166.771530 -53.1385307 113.632996 163.418503 -53.6574631 109.761040 158.240143 -53.9027443 104.337402 156.478882 -53.8089523 102.669930 158.187408 -53.0656128 105.121796 161.375366 -53.8903961 107.484970 164.176849 -53.5839615 110.592880 163.574799 -52.7410469 110.833755 164.843063 -52.6243057 112.218758 165.987473 -53.2754784 112.711990 169.274460 -53.5544815 115.719978 167.454010 -52.4152565 115.038757 166.879013 -53.1226578 113.756355 162.296005 -53.5352020 108.760803 158.493393 -54.7359657 103.757431 156.721985 -53.1415825 103.580399 158.332535 -52.5940781 105.738464 160.625610 -52.3889008 108.236702 164.343292 -53.0330162 111.310280 163.334625 -52.2220383 111.112579 164.885696 -52.9631233 111.922569 164.449844 -52.3473091 112.102531 166.675308 -52.9505310 113.724785 167.682358 -52.9631805 114.719170 Last Updated: July 10, 2019 -----------------------------------------------------------------------------