ISCCP D2 Native Data Set Readme File 1.0 Introduction This file contains information about the International Satellite Cloud Climatology Project (ISCCP) D2 native (NAT) data set. (ISCCP_D2_NAT) The data files are in native format. The home page for ISCCP is located at http://isccp.giss.nasa.gov/ This readme file also includes the following sections: Section 2.0 - provides general information about the data set. Section 3.0 - describes the format of the data. Section 4.0 - provides the user with science parameter information Section 5.0 - describes the sample read software. Section 6.0 - discusses how to invoke the run-time executable. Section 7.0 - provides an example of an actual run of the sample read software. If users have questions while using the ISCCP_D2_NAT sample read software, please contact the Langley Data Center User and Data Services office at: Langley Atmospheric Science Data Center User and Data Services Office NASA Langley Research Center Mail Stop 157D 2 South Wright Street Hampton, VA 23681-2199 U.S.A. Email: support-asdc@earthdata.nasa.gov Phone: (757) 864-8656 FAX: (757) 864-8807 URL: http://eosweb.larc.nasa.gov 2.0 Data Set Description Documentation on the ISCCP_D2_NAT data set can be obtained from the following URL: http://isccp.giss.nasa.gov/doc/documents.html Contact for scientific inquiries: Dr. William B. Rossow NASA Goddard Institute for Space Studies 2880 Broadway New York, NY 10025 email: clwbr@giss.nasa.gov Phone: 212-678-5567 FAX: 212-678-5662 Contact for technical assistance: Violeta Golea NASA Goddard Institute for Space Studies 2880 Broadway, Rm 322A New York, NY 10025 email: vgolea@giss.nasa.gov 3.0 Format and Packaging There are 2 naming conventions for these files. The first convention is as follows: d2.YYYYMMHH where YYYY is the year, MM is the month, HH is the hour in GMT (00, 03, 06, 09, 12, 15, 18 or 21) There are 4 files that would go with an ISCCP_D2_NAT data file. They are a volume identification file (volid), a table of contents (toc1) file, ancillary data file (ancil) and a Calibration Correction Factors/Meteosat RS Correction Factors (calmetcor) file. Each file is followed with a .YYYY . The ancillary files are complete for the year. For example: d2ancil.1993 d2calmetcor.1993 d2toc1.1993 d2volid1.1993 The second file naming convention is as follows: ISCCP.TTTTTT.V.SATID.YYYY.MM.DD.HH.MM.DCN TTTTTT - data type D2 - ISCCP D2 data file D2READ - ISCCP D2 Read software V - version number SATID - GLOBAL - used if multiple or no satellites apply YYYY - year = 1981...2005 (always 4 numbers, fill = 9999) MM - month number = 1...12 (always 2 numbers, fill = 99) DD - day of month = 1...31 (always 2 numbers, fill = 99) HHMM - hour-minute GMT = 0000...2100 (always 4 characters, fill = 9999) DCN - data center name where data originated. For non-data files, the date and time fields may be fill values. Example: ISCCP.D2.0.GLOBAL.1995.10.01.0300.GPC (data file) ISCCP.D2TOC.0.GLOBAL.1995.10.99.9999.GPC (table of contents) 4.0 Science Parameters Information The ISCCP_D2_NAT data set contains 3-hourly, 280 KM equal-area grid data from various polar and geostationary satellites. More information on the ancillary and data files can be obtained from the International Satellite Cloud Climatology Project (ISCCP) Documentation of New Cloud Datasets documentation available at URL http://isccp.giss.nasa.gov/doc/documents.html 5.0 Description of Sample Read Software The FORTRAN program isccp_d2_nat_read.f has been provided by the data producer as a sample program. It is up to the user to modify the program to output the data of interest. The code was developed using a f77 compiler, it has not been approved for use with f90 or f95 compilers. 6.0 Implementing Sample Read Software The program can be compiled with a simple f77 command line argument. A sample of the compilation output a user can expect to see follows: - For SunOS f77 -o rd_d2 d2read.f d2read.f: MAIN sample: d2open: d2read: d2rec: eq2sq: d2phys: midprs: rdanc: printi: printr: center: cldhgt: BLOCK DATA: - For SGI's f77 -o rd_d2 -bytereclen d2read.f Prior to running the program, the data file must be linked to fort.10 and the ancillary file must be linked to fort.9 These files are what the program will open and read. There are several ways to create this file: We recommend the unix "ln" command: ln -s fort.9 ln -s fort.10 In addition the program writes output to a file called fort.90. 7.0 A sample run After the program has been successfully compiled and the file fort.10 has been created, the read program can be executed. A sample of the output follows: D2 PREFIX INFORMATION: YEAR 93 MONTH 12 DAY 31 UTC 3 D1PHYS: LAT BAND 1 CONVERTED TO PHYSICAL VALUES D1PHYS: LAT BAND 2 CONVERTED TO PHYSICAL VALUES D1PHYS: LAT BAND 3 CONVERTED TO PHYSICAL VALUES D1PHYS: LAT BAND 4 CONVERTED TO PHYSICAL VALUES . . . . D1PHYS: LAT BAND 35 CONVERTED TO PHYSICAL VALUES D1PHYS: LAT BAND 36 CONVERTED TO PHYSICAL VALUES *************************************************************************************** ************* PROCESSING EQUAL-AREA LON/LAT 1 36 PRINTI: COUNT VALUES FOR ALL VARIABLES 1 2 3 4 5 6 7 8 9 10 VARIABLE (001-010) 36 1 1 1 1 31 0 151 26 0 VARIABLE (011-020) 6 6 19 26 13 26 26 26 52 133 . . . VARIABLE (121-130) 146 117 85 64 20 11 18 128 41 130 PRINTR: PHYSICAL VALUES FOR ALL VARIABLES 1 2 3 4 5 6 7 8 9 10 VARIABLE (001-010) 36.00 1.00 1.00 1.00 1.00 31.00 0.00 75.50 1 3.00 0.00 VARIABLE (011-020) 3.00 3.00 9.50 13.00 6.50 13.00 13.00 13.00 2 6.00 660.00 . . . VARIABLE (111-120)-1000.00-1000.00-1000.00-1000.00-1000.00 298.70 1.50-1000.00 0.00 1000.00 VARIABLE (121-130) 299.20 285.20 267.20 253.10 95.00 192.00 204.50 3.81 1.20 258.00 CENTER: CENTER LON/LAT 1.25 -1.25 MIDPRS: ACTUAL PRESSURE LAYER MID-POINTS (MB) 900.00 740.00 620.00 500.00 375.00 245.00 137.50 CLDHGT: CLOUD TOP HEIGHT (M) 3385. *************************************************************************************** . . . D1PHYS: LAT BAND 71 CONVERTED TO PHYSICAL VALUES D1PHYS: LAT BAND 72 CONVERTED TO PHYSICAL VALUES NUMBER OF FULL BOXES: 6417 NORMAL END OF PROGRAM Last updated: July 31, 2001 April 30, 2009