******************************************************************************** * * * Readme file for the ATOST ER2 MAS Data Sets * * * ******************************************************************************** 1.0 Introduction This file contains information about the sample read software and data files for the NASA ER2 Moderate Resolution Imaging Spectroradiometer (MODIS) Airborne Simulator (MAS). This software will read the data set: Atlantic-THORPEX Observing System Test (ATOST_ER2_MAS) The ER2 MAS data files range in size from 8 Mbytes to 1.1 Gbytes. The data files are written in netCDF (Common Data Format). NCSA's (National Center for Supercomputing Applications) HDF (Hierarchical Data Format) libraries with the netCDF extensions are required to build the read software. These libraries can be obtained via anonymous ftp from ftp.ncsa.uiuc.edu (141.142.20.50) or via the World Wide Web at http://hdf.ncsa.uiuc.edu. This readme file includes the following sections: Section 2.0 - Data Set Description Section 3.0 - Format and Packaging Section 4.0 - Science Parameter Information Section 5.0 - Description of Sample Read Software Section 6.0 - Implementing Sample Read Software Section 7.0 - Sample Output If you have questions while using the ATOST_ER2_MAS sample read software, please contact the NASA 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 FAX: (757)864-8807 URL: http://eosweb.larc.nasa.gov 2.0 Data Set Description The MODIS Airborne Simulator (MAS) is an airborne scanning spectrometer that acquires high spatial resolution imagery of cloud and surface features from its vantage point on-board a NASA ER-2 high-altitude research aircraft. Data acquired by the MAS are helping to define, develop, and test algorithms for the Moderate Resolution Imaging Spectroradiometer (MODIS), a key sensor of NASA's Earth Observing System (EOS). The MODIS program will emphasize the use of remotely sensed data to monitor variation in environmental conditions for assessing both natural and human-induced global change. The MAS spectrometer acquires high spatial resolution imagery in the range of 0.55 to 14.3 microns. A total of 50 spectral bands are available in this range. Pre-1995 the digitizer was configured for each mission to record a pre-selected group of 12 bands during the flight. For most of these missions the digitizer was configured to record four 10-bit channels and seven 8-bit channels. A 50-channel digitizer which records all 50 spectral bands at 12 bit resolution became operational in January 1995. The MAS spectrometer is mated to a scanner sub-assembly which collects image data with an IFOV of 2.5 mrad, giving a ground resolution of 50 meters from 20000 meters altitude, and a cross track scan width of 85.92 degrees. For information about the ATOST mission see: http://www-angler.larc.nasa.gov/bangor/ and http://mas.arc.nasa.gov/data/deploy_html/atost2003_home.html 2.1 Instrumentation Description For a description of the MODIS Aircraft Simulator see: http://mas.arc.nasa.gov/ 2.2 Data Quality Note that spectral response curves used for processing raw MAS instrument counts to calibrated radiances were "atmospherically corrected" and smoothed. This atmospheric correction was done to the (approximate) 5 meter path between the source and the MAS instrument during the instrument's calibration. MAS calibrated radiances are not atmospherically corrected to account for atmospheric profiles, absorbing and emmitting gases, clouds, or aerosols in the sensor to Earth path. 2.3 Science Contact Questions pertaining to the data values contained within these files should be directed to: Michael Fitzgerald Airborne EOS Data Production Mgr. NASA Airborne Sensor Facility (SAIC) Ames Research Center Building 240, Room 219 Mail Stop 240-6 Moffett Field, CA 94035-1000 Office phone (650) 604 2872 Fax (650) 604 4987 E-mail mfitzgerald@mail.arc.nasa.gov 3.0 Format and Packaging The following files are defined for this distribution: Filename Format ---------------------- -------------------- atost_er2_mas_read.c C Source Code atost_er2_mas_read.f Fortan Source Code atost_er2_mas_read_idl.pro IDL Source Code atost_er2_mas_constant.i Fortran Include File readme_atost_er2_mas This readme file Note: Both C and Fortran source code use the HDF libraries. The naming convention used for the files is: atost_mas_FFFFF_TT_YYYYMMDD_SSSS_EEEE_ver.hdf where: FFFFF Flight Number TT Track Number YYYY Year 4-digit MM Month 2-digit DD Day 2-digit SSSS Start Time EEEE End Time ver Data Version For example: atost_mas_04613_01_20031106_1926_1928_v01.hdf This example is a Level 1B file on flight 04-613 track 01 on November 6, 2003 with a starting time of 19:26 and an ending time of 19:28 version 01 hdf format. Flight No. Date 04-613 06 November 2003 04-614 13 November 2003 04-615 14 November 2003 04-616 17 November 2003 04-617 19 November 2003 04-618 28 November 2003 04-619 02 December 2003 04-620 03 December 2003 04-621 04 December 2003 04-622 05 December 2003 04-623 08 December 2003 04-624 10 December 2003 04-625 11 December 2003 04-626 14 December 2003 04-627 17 December 2003 4.0 Science Parameters Information For information about the MAS science parameters see: http://ltpwww.gsfc.nasa.gov/MODIS/MAS/masdug.html 5.0 Description of Sample Read Software There are three sample read programs developed for the ATOST_ER2_MAS data set. One was written in the C programming language, another one was written in the Interactive Data Language (IDL) and the final one was written in Fortran. All programs have been tested on SGI under OS 6.5.11m. The IDL program was developed and tested using IDL 5.3 on an SGI system. Information about IDL can be obtained at the Research Systems, Inc. web site at: http://www.rsinc.com/ 5.1 The C Program The atost_er_mas_read.c program is meant to be an example program provided for the user's convenience. With minor modifications, the program can be compiled and executed on many different platforms. This read software is heavily based upon the NCSA distributed version of the netCDF utility "ncdump". In fact, the program should work for most, if not all, netCDF formatted files. Please see the program source code for copyright information. 5.2 The IDL Program The atost_er2_mas_read_idl.pro program will read data from the input file and write it out in ASCII format to a file with the same name but with .rpt as the extension. Under Unix the user must have X-Windows running in order for the user interface to work properly. The user selects which file to use based on the selection chosen from a file dialog box. The application then prompts the user for global attributes and then for the selection of which data item(s) to dump to file. Special Note: Selecting a 0 will dump everything which will create a huge ASCII file. 5.3 The Fortran Program For the Fortran program two files are used to generate the Fortran read software: atost_er2_mas_read.f and atost_er2_mas_constant.i. The Fortran read software is available at the Atmospheric Sciences Data Center or may be downloaded from the MAS URL at: http://ltpwww.gsfc.nasa.gov/MODIS/MAS/sw.html The atost_er2_mas_read.f program is interactive in nature and allows the user to cycle through portions of the data file. Section 7.3 shows a sample session using this application. Also, there is a viewer for MAS Imagery called SHARP that is available at the following URL: http://cimss.ssec.wisc.edu/~gumley/sharp/sharp.html 6.0 Implementing Sample Read Software The following sections detail how to compile and link the various applications. 6.1 How to Compile the Sample Read Software The user can build the sample read program from the C or Fortran source files. 6.1.1 To build the executable using the C source file at the UNIX commmand line prompt type: cc (or acc) -DNO_HAVE_PROTOTYPES -DNO_STDARG -I/usr/local/hdf/include -o atost_er2_read_netcdf_c atost_er2_read_netcdf.c -L/usr/local/hdf/lib -lmfhdf -ljpeg -ldf -lz /usr/lib/libm.a 6.1.2 To build the executable using the Fortran source files for the ER2_MAS data set, type: f77 -DNO_HAVE_PROTOTYPES -DNO_STDARG -I/usr/local/hdf/include -o atost_er2_mas_read_netcdf_f atost_er2_mas_read_netcdf.f atost_er2_mas_constant.i -L/usr/local/hdf/lib -lmfhdf -ljpeg -ldf -lz /usr/lib/libm.a NOTE 1: The -I (include) and -L (library) hdf directory paths may differ on your system. /usr/lib/libm.a should be the path to your system math libraries. Also the HDF libraries on your target machine may be 32 bit instead of 64 bit. NOTE 2: The include file atost_er2_mas_constant.i should be in the working directory. A warning is issued for line 55 of atost_er2_mas_constant.i for an unused variable. This does not effect the use of this program. 6.2 How to Run the Sample Read Software This section illustrates the invocation of the various applications. 6.2.1 Compiling 'C' program using HDF4.1r5 (tested on Sun 4) /usr/local/SUNWspro/bin/cc -w -DNO_HAVE_PROTOTYPES -DNO_STDARG -I/fs1/HDF4.1r5/solaris8_32/include \ -o atost_er2_mas_read_c atost_er2_mas_read_netcdf.c \ -L/fs1/HDF4.1r5/solaris8_32/lib -lmfhdf -ldf -lz -ljpeg \ -L/usr/lib -lnsl atost_er2_mas_read_c Currently, the executable atost_er2_mas_read_c program does not accept command line arguments. When the program is executed, it requests an input filename. The output file name is automatically created by appending ".rpt" to the input file name. This code assumes that the data and code are located in the working directory. The report file generated will also be written to the working directory. After entering the filename, the user is presented with a parameter selection list. The user can select some of the parameters or all of the parameters to be written into the output file. At this point, the program generates the report file and exits. To begin program execution for the 'C' executable at the UNIX command line prompt, type: % atost_er2_mas_read_c 6.2.2 Compile using IDL The idl read software can be compiled and run through the IDL development environment. The idl read software can also be started by compiling and then executing the program. At the UNIX command line prompt, type: % idl IDL> .compile atost_er2_mas_read_netcdf_idl.pro IDL> atost_er2_mas_read_netcdf_idl 6.2.3 Compiling Fortran program using HDF4.1r1 (for Sun 4) f77 -xarch=v9 -o atost_er2_mas_read_f atost_er2_mas_read_netcdf.f \ -I/fs1/HDF4.1r5/solaris8_64/include \ -L/fs1/HDF4.1r5/solaris8_64/lib -lmfhdf -ldf -lz -ljpeg \ -L/usr/lib -lnsl atost_er2_mas_read_f (for SGI) f77 -64 -mips4 -O -s -o atost_er2_mas_read_f atost_er2_mas_read_netcdf.f \ -I/fs1/HDF4.1r5/irix_64/include \ -L/fs1/HDF4.1r5/irix_64/lib -lmfhdf -ldf -lz -ljpeg atost_er2_mas_read_f (for HP) f77 -O -o read_mas_f atost_er2_mas_read_netcdf.f -I/usr/local/hdf/include /usr/local/hdf/lib/libmfhdf.a /usr/local/hdf/lib/libdf.a /usr/local/hdf/lib/libjpeg.a /usr/local/hdf/lib/libz.a /usr/lib/libm.a Currently, the executable atost_er2_mas_read_f program does not accept command line arguments. When the program is executed, it requests an input filename. An output filename is not automatically created. After entering the filename, the user must input a series of (carriage returns) or n - (no's) for a series of output requests. To begin program execution for the Fortran executable, at the UNIX command line prompt, type: % atost_er2_mas_read_f A sample of the interactive program execution is provided in Section 7.2. 7.0 Sample Output ------------------------------------------------------------------------------------- 7.1 Output demonstration of C sample read software. Complete list of parameters for mas_read_netcdf.c This program reads ER2 MAS netCDF data. Please enter Q to Quit or C to continue c Please enter netCDF file name to read: atost_mas_04626_10_20031214_1957_2024_v01.hdf Report file name is: atost_mas_04626_10_20031214_1957_2024_v01.hdf.rpt Item Data Type Label(dimension lengths) ==== ========= ======================== 1 float Left50%ResponseWavelength(50) 2 float Central100%ResponseWavelength(50) 3 float Right50%ResponseWavelength(50) 4 float EffectiveCentralWavelength_IR_bands(50) 5 float TemperatureCorrectionSlope(50) 6 float TemperatureCorrectionIntercept(50) 7 float SolarSpectralIrradiance(50) 8 char DataSetHeader(131 X 80) 9 long ScanLineCounter(9999) 10 long GreenwichMeanTime(9999) 11 long YearMonthDay(9999) 12 short AircraftRollCount(9999) 13 short BlackBody1Temperature(9999) 14 short BlackBody2Temperature(9999) 15 float ScanRate(9999) Please choose the numbers of the data items you wish to dump Enter -1 to display additional items or zero to end selection process . . Output continues in this manner until all items are shown. . NOTE: if you enter 0 as very first entry, all variables will be displayed 11 0 Would you like the global attributes included in the report? (Y/N)y *** THE OUTPUT FILE FOR THE SELECTION ABOVE**** This is the report file for the atost_mas_04626_10_20031214_1957_2024_v01.hdf.rpt file ****************** START GLOBAL ATTRIBUTE SECTION ****************** CreationDate = 18-Feb-2004 16:08:06 AircraftPlatform = NASA ER-2 (806) NavFormatCode = Format (A-2) LocationCode = Inertial (INU) AltitudeCode = Inertial (INU) NavDataSource = ER2 navigation recorder NavDataPath = /nav/2004/er2/04-626 CalibrationName = A-TOST_103003_011204 Reference = NCSA HDF Reference Manual, Version 4.1r4, 2000 title = MODIS Airborne Simulator (MAS) Level-1B Data ExperimentName = A-TOST FlightNumber = 04-626 FlightDate = 14 Dec 2003 SiteLineRun = void GeographicArea = Canada SRF_FTP = ftp://asapdata.arc.nasa.gov/mas/srf/Nov_03/ SRF_dataset = /rarray/calibrat/mas/srf/Nov_03/ FlightLineNumber = 10s TotalFlightLines = 13s DataUsersGuideSource = http://mas.arc.nasa.gov/ SoftwareVersion = Level-1b Version 10.2.3 UR CalibrationVersion = Version 1.0 Calibration data_set = MAS A-TOST day_night_flag = D granule_version = 1s metadata_version = 1.0.0 data_quality = Good Other_Aircraft_Sensors = NAST-I, NAST-M, in situ O3, S-HIS, VIS Principal_Investigator = Murray & Smith (LaRC) Navigational_Precision = Single lat_UL = 55.142601f lon_UL = -76.200500f lat_UR = 55.309643f lon_UR = -75.710876f lat_LL = 52.469826f lon_LL = -73.734299f lat_LR = 52.619484f lon_LR = -73.253120f begin_date = 20031214 195720 end_date = 20031214 202408 RunTime = 342,260 ms, or 34 ms/scanline CompletionDate = 18-Feb-2004 16:14:59 producer_granule_id = MASL1B_04626_10_20031214_1957_2024_V01.hdf granule_size = 898282638 ****************** END GLOBAL ATTRIBUTE SECTION ****************** YearMonthDay _FillValue = -999 comment = YYYYMMDD 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, 20031214, etc... ------------------------------------------------------------------------------------- 7.2 Output demonstration of Fortran sample read software. Sample read software for atost_er2_mas_read_f: WARNING: This version fixes a bug in HDF3.3r3 Enter HDF file name : atost_mas_04626_10_20031214_1957_2024_v01.hdf name= atost_mas_04626_10_20031214_1957_2024_v01.hdf HDF file id = 393216 # of Global Attributes = 44 # of Scientific Data Sets (SDS"s) = 37 Read Global Attributes ? ( or n ) : ******** GLOBAL ATTRIBUTE ********* Attribute_Name = CreationDate Attribute Index = 0 Number_Type = 4 Count = 20 - - - Attribute Value - - - 18-Feb-2004 16:08:06 ********************************** Continue ? ( or n ) : ******** GLOBAL ATTRIBUTE ********* Attribute_Name = AircraftPlatform Attribute Index = 1 Number_Type = 4 Count = 15 - - - Attribute Value - - - NASA ER-2 (806) ********************************** Continue ? ( or n ) : ******** GLOBAL ATTRIBUTE ********* Attribute_Name = NavFormatCode Attribute Index = 2 Number_Type = 4 Count = 12 - - - Attribute Value - - - Format (A-2) ********************************** Continue ? ( or n ) : etc... . . Output continues in this manner until all GLOBAL ATTRIBUTES are shown. . Read Scientific Data Set"s (SDS"s) ? ( or n) : ************* Scientific Data Set ************** SDS_Name = Left50%ResponseWavelength Index = 0 SDS_ID = 262144 # of Dims = 1 DimSizes = 50 0 0 0 0 Number_Type = 5 Number of Attributes = 1 - - - Sample Data Value - - - 0.531000018 - - - - - - - - - - - - - - - Read SDS attribute string ? ( or n ) : ************* Scientific Data Set ************** SDS_Name = Right50%ResponseWavelength Index = 2 SDS_ID = 262146 # of Dims = 1 DimSizes = 50 0 0 0 0 Number_Type = 5 Number of Attributes = 1 - - - Sample Data Value - - - 0.573000014 - - - - - - - - - - - - - - - Read SDS attribute string ? ( or n ) : . . Output continues in this manner until all Scientific Data Sets are shown. . -------- Local Attribute ----------- Attribute_Name = units Attribute Index = 1 Number_Type = 4 Count = 29 - - - Attribute Value - - - watts/meter2/steradian/micron -------- Local Attribute ----------- Attribute_Name = scale_factor Attribute Index = 2 Number_Type = 5 Count = 50 - - - Attribute Value - - - 0.10000 0.10000 0.10000 0.10000 0.10000 0.10000 0.10000 0.10000 0.10000 0.10000 0.01000 0.01000 0.01000 0.01000 0.01000 0.10000 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.00100 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 0.01000 Enter Pixel(1-716), Record(1- 9999), Channel(1-12) ? Last Updated: