Langley DAAC Version Number: LD_008_004_006_00_00_0_19990526 ERBE S-4N Readme 1.0 Introduction This file contains information about the Earth Radiation Budget Experiment (ERBE) Regional, Zonal, and Global Averages Output Product (S-4N) Data Set sample read software and data files. This document provides the user with the necessary information to use the ERBE data for scientific research studies. The S-4N data set consists of nonscanner data processed without scene identification information from the scanner. This "readme" files includes the following five other sections: * Section 2.0 - describes the "C" program (source file) * Section 3.0 - describes how to create the executable from the "C" program. * Section 4.0 - demonstrates how to invoke the run-time executable. * Section 5.0 - provides general information on the data sets. * Section 6.0 - provides more detailed implementation notes. If users have questions while using the ERBE S-4N sample read software, please contact the Langley DAAC Science, Users and Data Services office at: EOSDIS Langley DAAC Science, Users and Data Services Office NASA Langley Research Center Mail Code 157D 2 South Wright Street Hampton, Virginia 23681-2199 U.S.A. E-mail: support-asdc@earthdata.nasa.gov Phone: (757)864-8656 FAX: (757)864-8807 NOTE: All files are in the Native / Binary format. Please note that all files are "zipped" and will expand to approximately 3 times their original size when "unzipped." Once the files are "unzipped," the user will notice in the current working area that a directory has been created. The directory will appear in the format of s4n_yymm_s where yy represents the year, mm represents the month, and s represents the satellite code number. In this directory, 26 files will be listed. The instructions that follow will explain the file structure. 2.0 Read Software Files The read program was developed in the "C" language. This program has been tested on the "Sun4", and the "HP" UNIX based workstations. There are no library routines that need to be loaded or linked. The file and its purpose is listed as follows: s4n_read.c - reads the ERBE S-4N data. 3.0 Creating C Executable Files To use the command line to compile the S-4N read software type: %cc -w -o read_s4n s4n_read.c 4.0 Invoking Read Software This section illustrates the invocation of the executable file. Section 4.1 describes how to run the read program for the ERBE S-4N data set. 4.1 Running the Read Program for the ERBE S-4N Data Set When this program is executed, it requires a filename with all the input files on it with only one file name per line. The following example will explain this: example of what would be on file (input file): s4n01_prokey_89047 s4n03_nscalf_89047 s4n04_sc2.5_89047 s4n05_sc5.0_89047 s4n06_sc10.0_89047 s4n07_sc2.5z_89047 s4n08_sc5.0z_89047 s4n09_sc10z_89047 s4n10_scglb_89047 s4n11_mnf5.0_89047 s4n12_mnf10_89047 s4n13_mnf5z_89047 s4n14_mnf10z_89047 s4n15_mnfglb_89047 s4n16_wnf5.0_89047 s4n17_wnf10_89047 s4n18_wnf5z_89047 s4n19_wnf10z_89047 s4n20_wnfglb_89047 s4n21_msf10_89047 s4n22_msf10z_89047 s4n23_msfglb_89047 s4n24_wsf10_89047 s4n25_wsf10z_89047 s4n26_wsfglb_89047 The program will first prompt the user to enter the filename which contains the twenty six data files to be read. The program then will prompt the user to enter an output filename to write the output from the program to. After all filenames have been entered the program begins prompting for the processing options that define which data files out of the twenty six files are to be processed. The following list will explain these option combinations: Nonscanner Processing Options Variable/definition Allowed values Definition ------------------ ------------- ---------- instrument 2 2=nonscanner resolution 2,3 2=5.0 3=10.0 field-of-view 2 2=wide type of coverage 1,2,3 1=regional 2=zonal 3=global irecf - first region to read 1-10368 irecl - last region to read 1-10368 iray[0]- dgma data values 0,1 0=no, 1=yes iray[1]- hgma data values 0,1 0=no, 1=yes iray[2]- daily data values 0,1 0=no, 1=yes iray[3]- hourly data values 0,1 0=no, 1=yes idata[0]- longwave values 0,1 0=no, 1=yes idata[1]- shortwave values 0,1 0=no, 1=yes idata[2]- net values 0,1 0=no, 1=yes idata[3]- solar incidence 0,1 0=no, 1=yes idata[4]- albedo values 0,1 0=no, 1=yes idata[5]- no. days of sw 0,1 0=no, 1=yes idata[6]- no. days of lw 0,1 0=no, 1=yes idata[7]- no. of hrs. of sw 0,1 0=no, 1=yes idata[8]- no. of hrs. of lw 0,1 0=no, 1=yes By modifying the variable inputs, the user can select the type of instrument, the resolution, the field-of-view, and the type of radiant flux values or statistics they wish. After all the processing options have been selected the program begins processing and writes all the output to the output file that was selected beforehand. 5.0 Data Set Information The S-4N data set contains averages of flux and albedo on regional, zonal, and global scales for nonscanner data. It is available as a combination of all operational spacecraft (ERBS, NOAA-9, and NOAA-10) for the wide field-of-view (WFOV) data. It is available as a combination of the ERBS, and NOAA-9 spacecraft for medium field-of-view data. The S-4N contains five files of WFOV numerical filter data and three files of WFOV shape factor data. Monthly (day), monthly (hour), daily, and monthly hourly averages are determined for each region. The data are represented in 8-, 16-, and 32-bit integers. The values contained are as follows: * Geographic scene type * Monthly mean shortwave flux * Monthly mean longwave flux * Monthly mean albedo * Monthly mean net flux * Monthly total integrated solar incidence * Statistics such as the number of days that contain shortwave/ longwave measurements for a given hour 5.1 Notes On Data FIRST RECORD OF DATA FROM FIRST DATA GRANULE: -------------------------------------------- PHYSICAL HEADER CONTENTS: (0) subsystem indicator : 2 (1) product code : 7 (2) spacecraft indicator : 244 (3) whole julian date - high : 7617 (4) whole julian date - low : 5000 (5) fractional julian date : 1 (6) processed version counter : 95 (7) year processed : 5 (8) month processed : 31 (9) day processed : 15 (10) hour processed : 12 (11) minute processed : 38 (12) second processed : 0 ERBE Product : S-4N Spacecraft : ERBS, NOAA-9, & NOAA-10 Processing date : 5/31/1995 Data Date : 89/04/01 Processing version: 1 NONSCANNER SCALE FACTORS 1 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 1 1 1 10 10 1000 10 10 1000 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 DATA DATE = 8904.000 SATELLITE= 7.000 FILE ID 14.000 REGION NUMBER 1.000 NONSCANNER GEOGRAPHIC SCENE TYPE 0.000 DEAD SCANNER FLAGS 1.000 1.000 1.000 LW-MONTHLY(DAY) 189.900 SW-MONTHLY(DAY) 119.600 TSOLRD-MONTHLY(DAY) 162139.875 ALBEDO-MONTHLY(DAY) 0.531 LW-MONTHLY(HR) 188.800 SW-MONTHLY(HR) 119.600 TSOLRH-MONTHLY(HR) 162139.875 ALBEDO-MONTHLY(HR) 0.531 LW-DAILY 198.100 188.400 177.100 178.600 178.500 180.000 181.700 183.500 186.300 184.400 187.300 193.200 198.000 202.100 201.700 200.600 198.500 191.700 190.600 190.600 190.600 190.600 190.600 190.600 190.600 190.600 190.600 190.600 190.600 190.600 32767.000 SW-DAILY 70.100 69.500 71.000 59.400 88.600 32767.000 91.800 88.400 89.600 82.000 103.200 32767.000 114.800 52.200 32767.000 32767.000 128.400 142.600 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 32767.000 SOLARD-DAILY 2791.300 2942.400 3097.200 3255.870 3418.660 3585.920 3758.180 3936.370 4122.430 4323.170 4527.780 4730.730 4931.950 5131.390 5329.000 5524.740 5718.540 5910.360 6100.160 6287.890 6473.490 6656.930 6838.170 7017.150 7193.830 7368.180 7540.150 7709.710 7876.810 8041.420 327.670 ALBEDO-DAILY 0.603 0.567 0.550 0.219 0.311 0.000 0.293 0.269 0.522 0.228 0.547 0.000 0.279 0.122 0.000 0.000 0.269 0.579 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 32767.000 NDSW-DAILY 2.000 2.000 4.000 1.000 1.000 0.000 1.000 2.000 2.000 1.000 2.000 0.000 1.000 1.000 0.000 0.000 1.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 32767.000 NDLW-DAILY 2.000 2.000 4.000 1.000 1.000 0.000 1.000 2.000 2.000 1.000 2.000 0.000 1.000 1.000 0.000 0.000 1.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 32767.000 LW-MONTHLY HOURLY 189.400 189.300 189.100 188.900 188.800 188.600 188.400 188.300 188.100 188.000 188.200 188.800 189.300 189.200 189.500 189.500 189.400 189.200 189.000 188.900 188.700 188.500 188.400 188.200 SW-MONTHLY HOURLY 8.400 11.300 18.300 30.400 51.600 75.600 100.500 124.400 145.600 162.600 175.400 182.100 181.400 173.700 159.800 142.500 121.800 98.500 74.200 50.700 30.100 18.100 11.300 8.400 SOLARH-MONTHLY HOURLY 160.240 216.240 348.980 579.460 970.320 1414.850 1875.070 2319.610 2718.170 3043.590 3273.700 3392.820 3392.820 3273.700 3043.590 2718.170 2319.610 1875.070 1414.850 970.320 579.460 348.980 216.240 160.240 ALBEDO-MONTHLY HOURLY 0.527 0.524 0.523 0.525 0.531 0.535 0.536 0.536 0.536 0.534 0.536 0.537 0.535 0.530 0.525 0.524 0.525 0.525 0.525 0.523 0.520 0.519 0.522 0.526 NHSW-MONTHLY HOURLY 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 1.000 2.000 5.000 3.000 1.000 2.000 2.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 NHLW-MONTHLY HOURLY 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 1.000 2.000 5.000 3.000 1.000 2.000 2.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 CONTACTS FOR DATA PRODUCTION INFORMATION: Dr. Bruce R. Barkstrom ERBE Experiment Scientist and Science Team Leader NASA Langley Research Center 6.0 Implementation Notes This interactive read program first expects to read information from an input data file. The program reads in a filename from the input file one at a time. The program will open the file and call the necessary function routines to decode the data records from this file. The program continues to read and open and process files until it reaches the end of the input file. After reaching the end of information contained on the input file the program continues and begins to process the data and writes the output to the output file.