Example for Section 2, Data Characteristics Remote Sensing Data This example is from highly structured BOREAS Data Set Documentation. This is one of several possible ways to describe the characteristics of your data. The numerous subsections could be variously collapsed and the variable descriptions could be could be presented in a different format. The data file being described is actually an inventory of the data that were collected. Complete documentation can be accessed at http://www.daac.ornl.gov/BOREAS/guides/RSS14_GOES7_L2.html. From... BOREAS RSS-14 Level-2 GOES-7 Shortwave and Longwave Radiation Images The BOREAS RSS-14 team collected and processed several GOES-7 and GOES-8 image data sets that covered the BOREAS study region. This data set contains images of shortwave and longwave radiation at the surface and top of the atmosphere derived from collected GOES-7 data. The data cover the time period of 05-Feb- 1994 to 20-Sep-1994. The images missing from the temporal series were zero- filled to create a consistent sequence of files. The data are stored in binary image format files. Note that the level-2 GOES-7 data are not contained on the BOREAS CD-ROM set. An inventory listing file is supplied on the CD-ROM to inform users of the data that were collected. See Sections 15 and 16 for information about how to acquire the data. 7. Data Description 7.1 Spatial Characteristics 7.1.1 Spatial Coverage The scanning system consists of a mirror that is stepped mechanically to provide north to south viewing, while the rotation of the GOES satellite provides west to east scanning. The mirror is stepped following each west to east scan. A sequence of 1,821 scans over 18.21 minutes is performed to provide a "full disk" view from just beyond the northern Earth horizon to just beyond the southern Earth horizon. Based on the level-1 GOES-7 images, the level-2 SW/LW product covers the entire 1,000-km by 1,000-km BOREAS region. This contains the Southern Study Area (SSA), the Northern Study Area (NSA), the transect region between the SSA and NSA, and some surrounding area. Based on information contained in the reference latitude and longitude files for the visible band (see Section 8.2), the following North American Datum of 1983 (NAD83) coordinates represent the nominal coverage of the level-2 SW/LW product: Latitude Longitude ---------- ----------- Northwest 64.757 N 107.037 W Northeast 65.911 N 87.120 W Southwest 47.646 N 109.210 W Southeast 47.916 N 98.087 W The NAD83 corner coordinates of the BOREAS region are: Latitude Longitude ---------- ----------- Northwest 59.97907 N 111.00000 W Northeast 58.84379 N 93.50224 W Southwest 51.00000 N 111.00000 W Southeast 50.08913 N 96.96951 W 7.1.2 Spatial Coverage Map Not available at this time. 7.1.3 Spatial Resolution The GOES-7 SW/LW images have a nominal pixel resolution of 8 x 8 km (approximately 14.2 x 6.6 km at BOREAS latitudes). For details, see Kelly, 1989. 7.1.4 Projection The BOREAS level-2 SW/LW data are stored in the same GOES 'perfect' projection as the level-1 images. The 'perfect' projection indicates that the satellite movement between temporal acquisitions has been removed so the images are aligned spatially. Detailed information about the projection is not currently available. 7.1.5 Grid Description Not available at this revision. 7.2 Temporal Characteristics 7.2.1 Temporal Coverage The SW images provide continuous coverage for the period of 05-Feb to 20-Sep- 1994. The LW images cover only the snow-free period from 23-May to 20-Sep-1994. 7.2.2 Temporal Coverage Map The times when images were acquired varied over the year. The following table gives the times when data are available: Dates Times --------------- ----------------- 05-Feb - 14-Feb 16:00 - 21:00 UTC 15-Feb - 14-Mar 15:30 - 22:00 UTC 14-Mar - 11-Apr 14:00 - 23:30 UTC 12-Apr - 02-May 13:00 - 00:30 UTC 03-May - 08-Aug 13:00 - 01:30 UTC 09-Aug - 28-Aug 13:00 - 00:30 UTC 29-Aug - 20-Sep 14:00 - 00:30 UTC 7.2.3 Temporal Resolution The images were acquired every 30 minutes during the specified time periods of each day. 7.3 Data Characteristics 7.3.1 Parameter/Variable The parameters contained in the inventory listing file are: Column Name ------------------------------ SPATIAL_COVERAGE DATE_OBS START_TIME END_TIME PLATFORM NW_LATITUDE NW_LONGITUDE NE_LATITUDE NE_LONGITUDE SW_LATITUDE SW_LONGITUDE SE_LATITUDE SE_LONGITUDE NUM_TIME_PERIODS NUM_NB_ALBEDO_TOA NUM_COLUMN_WATER_VAPOR NUM_DOWN_TOTAL_SW_TOA NUM_BB_ALBEDO_TOA NUM_NB_CLOUD_ALBEDO NUM_MIN_NB_ALBEDO_TOA NUM_DOWN_TOTAL_SW_SURF NUM_UP_TOTAL_SW_SURF NUM_BB_ALBEDO_SURF NUM_DOWN_PAR_SURF NUM_UP_PAR_SURF NUM_PAR_ALBEDO_SURF NUM_NET_LW_SURF CRTFCN_CODE 7.3.2 Variable Description/Definition The descriptions of the parameters contained in the inventory listing file are: Column Name Description ------------------------------ ------------------------------------------------ SPATIAL_COVERAGE The general term used to denote the spatial area over which the data were collected. DATE_OBS The date on which the data were collected. START_TIME The starting Greenwich Mean Time (GMT) for the data collected. END_TIME The ending Greenwich Mean Time (GMT) for the data collected. PLATFORM The object (e.g., satellite, aircraft, tower, person) that supported the instrument. NW_LATITUDE The NAD83 based latitude coordinate of the north west corner of the minimum bounding rectangle for the data. NW_LONGITUDE The NAD83 based longitude coordinate of the northwest corner of the minimum bounding rectangle for the data. NE_LATITUDE The NAD83 based latitude coordinate of the north east corner of the minimum bounding rectangle for the data. NE_LONGITUDE The NAD83 based longitude coordinate of the northeast corner of the minimum bounding rectangle for the data. SW_LATITUDE The NAD83 based latitude coordinate of the south west corner of the minimum bounding rectangle for the data. SW_LONGITUDE The NAD83 based longitude coordinate of the southwest corner of the minimum bounding rectangle for the data. SE_LATITUDE The NAD83 based latitude coordinate of the south east corner of the minimum bounding rectangle for the data. SE_LONGITUDE The NAD83 based longitude coordinate of the southeast corner of the minimum bounding rectangle for the data. NUM_TIME_PERIODS The number of 30-minute time periods of data available for the day. NUM_NB_ALBEDO_TOA The number of 30-minute time periods during the day when the narrow band (0.5 to 0.7 micrometers) albedo data at the top of the atmosphere are present. NUM_COLUMN_WATER_VAPOR The number of 30-minute time periods during the day when the column water vapor data are present. NUM_DOWN_TOTAL_SW_TOA The number of 30-minute time periods during the day when the downward total shortwave radiance data at the top of the atmosphere are present. NUM_BB_ALBEDO_TOA The number of 30-minute time periods during the day when the broad band (0.3 to 3.0 micrometers) albedo data at the top of the atmosphere are present. NUM_NB_CLOUD_ALBEDO The number of 30-minute time periods during the day when the narrow band (0.5 to 0.7 micrometers) cloud albedo data are present. NUM_MIN_NB_ALBEDO_TOA The number of 30-minute time periods during the day when the minimum narrow band (0.5 to 0.7 micrometers) albedo data at the top of atmosphere are present. NUM_DOWN_TOTAL_SW_SURF The number of 30-minute time periods during the day when the downward total shortwave radiance data at the surface are present. NUM_UP_TOTAL_SW_SURF The number of 30-minute time periods during the day when the upward total shortwave radiance data at the surface are present. NUM_BB_ALBEDO_SURF The number of 30-minute time periods during the day when the broad band (0.3 to 3.0 micrometers) albedo data at the surface are present. NUM_DOWN_PAR_SURF The number of 30-minute time periods during the day when the downward PAR (0.4 to 0.7 micrometers) data at the surface are present. NUM_UP_PAR_SURF The number of 30-minute time periods during the day when the upward PAR (0.4 to 0.7 micrometers) data at the surface are present. NUM_PAR_ALBEDO_SURF The number of 30-minute time periods during the day when the PAR (0.4 to 0.7 micrometers) albedo data at the surface are present. NUM_NET_LW_SURF The number of 30-minute time periods during the day when the net longwave radiance data (4.0 to 100.0 micrometers) data at the surface are present. CRTFCN_CODE The BOREAS certification level of the data. Examples are CPI (Checked by PI), CGR (Certified by Group), PRE (Preliminary), and CPI-??? (CPI but questionable). 7.3.3 Unit of Measurement The measurement units for the parameters contained in the inventory listing file on the CD-ROM are: Column Name Units ------------------------------ ------------------------------------------------ SPATIAL_COVERAGE [none] DATE_OBS [DD-MON-YYYY] START_TIME [HHMM GMT] END_TIME [HHMM GMT] PLATFORM [none] NW_LATITUDE [degrees] NW_LONGITUDE [degrees] NE_LATITUDE [degrees] NE_LONGITUDE [degrees] SW_LATITUDE [degrees] SW_LONGITUDE [degrees] SE_LATITUDE [degrees] SE_LONGITUDE [degrees] NUM_TIME_PERIODS [counts] NUM_NB_ALBEDO_TOA [counts] NUM_COLUMN_WATER_VAPOR [counts] NUM_DOWN_TOTAL_SW_TOA [counts] NUM_BB_ALBEDO_TOA [counts] NUM_NB_CLOUD_ALBEDO [counts] NUM_MIN_NB_ALBEDO_TOA [counts] NUM_DOWN_TOTAL_SW_SURF [counts] NUM_UP_TOTAL_SW_SURF [counts] NUM_BB_ALBEDO_SURF [counts] NUM_DOWN_PAR_SURF [counts] NUM_UP_PAR_SURF [counts] NUM_PAR_ALBEDO_SURF [counts] NUM_NET_LW_SURF [counts] CRTFCN_CODE [none] 7.3.4 Data Source The sources of the parameter values contained in the inventory listing file are: Column Name Data Source ------------------------------ ------------------------------------------------ SPATIAL_COVERAGE [Assigned by BORIS Staff] DATE_OBS [RSS14 image header] START_TIME [RSS14 image header] END_TIME [RSS14 image header] PLATFORM [RSS14 image header] NW_LATITUDE [RSS14 documentation] NW_LONGITUDE [RSS14 documentation] NE_LATITUDE [RSS14 documentation] NE_LONGITUDE [RSS14 documentation] SW_LATITUDE [RSS14 documentation] SW_LONGITUDE [RSS14 documentation] SE_LATITUDE [RSS14 documentation] SE_LONGITUDE [RSS14 documentation] NUM_TIME_PERIODS [RSS14 image header] NUM_NB_ALBEDO_TOA [RSS14 image header] NUM_COLUMN_WATER_VAPOR [RSS14 image header] NUM_DOWN_TOTAL_SW_TOA [RSS14 image header] NUM_BB_ALBEDO_TOA [RSS14 image header] NUM_NB_CLOUD_ALBEDO [RSS14 image header] NUM_MIN_NB_ALBEDO_TOA [RSS14 image header] NUM_DOWN_TOTAL_SW_SURF [RSS14 image header] NUM_UP_TOTAL_SW_SURF [RSS14 image header] NUM_BB_ALBEDO_SURF [RSS14 image header] NUM_DOWN_PAR_SURF [RSS14 image header] NUM_UP_PAR_SURF [RSS14 image header] NUM_PAR_ALBEDO_SURF [RSS14 image header] NUM_NET_LW_SURF [RSS14 image header] CRTFCN_CODE [Assigned by BORIS Staff] 7.3.5 Data Range The following table gives information about the parameter values found in the inventory table. Minimum Maximum Missng Unrel Below Data Data Data Data Data Detect Not Column Name Value Value Value Value Limit Cllctd -------------------------------------------------------------------------------- SPATIAL_COVERAGE N/A N/A None None None None DATE_OBS 05-FEB-1994 20-SEP-1994 None None None None START_TIME 0 0 None None None None END_TIME 2330 2330 None None None None PLATFORM GOES-7 GOES-7 None None None None NW_LATITUDE 64.757 64.757 None None None None NW_LONGITUDE -107.037 -107.037 None None None None NE_LATITUDE 65.911 65.911 None None None None NE_LONGITUDE -87.12 -87.12 None None None None SW_LATITUDE 47.646 47.646 None None None None SW_LONGITUDE -109.21 -109.21 None None None None SE_LATITUDE 47.916 47.916 None None None None SE_LONGITUDE -98.087 -98.087 None None None None NUM_TIME_PERIODS 1 26 None None None None NUM_NB_ALBEDO_TOA 0 26 None None None None NUM_COLUMN_WATER_ 0 26 None None None None VAPOR NUM_DOWN_TOTAL_SW_ 0 26 None None None None TOA NUM_BB_ALBEDO_TOA 0 26 None None None None NUM_NB_CLOUD_ALBEDO 0 26 None None None None NUM_MIN_NB_ALBEDO_ 0 26 None None None None TOA NUM_DOWN_TOTAL_SW_ 0 26 None None None None SURF NUM_UP_TOTAL_SW_SURF 0 26 None None None None NUM_BB_ALBEDO_SURF 0 26 None None None None NUM_DOWN_PAR_SURF 0 26 None None None None NUM_UP_PAR_SURF 0 26 None None None None NUM_PAR_ALBEDO_SURF 0 26 None None None None NUM_NET_LW_SURF 0 26 None None None None CRTFCN_CODE CPI CPI None None None None -------------------------------------------------------------------------------- Minimum Data Value -- The minimum value found in the column. Maximum Data Value -- The maximum value found in the column. Missng Data Value -- The value that indicates missing data. This is used to indicate that an attempt was made to determine the parameter value, but the attempt was unsuccessful. Unrel Data Value -- The value that indicates unreliable data. This is used to indicate an attempt was made to determine the parameter value, but the value was deemed to be unreliable by the analysis personnel. Below Detect Limit -- The value that indicates parameter values below the instruments detection limits. This is used to indicate that an attempt was made to determine the parameter value, but the analysis personnel determined that the parameter value was below the detection limit of the instrumentation. Data Not Cllctd -- This value indicates that no attempt was made to determine the parameter value. This usually indicates that BORIS combined several similar but not identical data sets into the same data base table but this particular science team did not measure that parameter. Blank -- Indicates that blank spaces are used to denote that type of value. N/A -- Indicates that the value is not applicable to the respective column. None -- Indicates that no values of that sort were found in the column. -------------------------------------------------------------------------------- 7.4 Sample Data Record SPATIAL_COVERAGE,DATE_OBS,START_TIME,END_TIME,PLATFORM,NW_LATITUDE, NW_LONGITUDE,NE_LATITUDE,NE_LONGITUDE,SW_LATITUDE,SW_LONGITUDE,SE_LATITUDE, SE_LONGITUDE,NUM_TIME_PERIODS,NUM_NB_ALBEDO_TOA,NUM_COLUMN_WATER_VAPOR, NUM_DOWN_TOTAL_SW_TOA,NUM_BB_ALBEDO_TOA,NUM_NB_CLOUD_ALBEDO, NUM_MIN_NB_ALBEDO_TOA,NUM_DOWN_TOTAL_SW_SURF,NUM_UP_TOTAL_SW_SURF, NUM_BB_ALBEDO_SURF,NUM_DOWN_PAR_SURF,NUM_UP_PAR_SURF,NUM_PAR_ALBEDO_SURF, NUM_NET_LW_SURF,CRTFCN_CODE 'REGION',05-FEB-94,0,2330,'GOES-7',64.757,-107.037,65.911,-87.12,47.646, -109.21,47.916,-98.087,10,10,10,10,10,10,10,10,10,10,10,10,10,0,'CPI' 'REGION',06-FEB-94,0,2330,'GOES-7',64.757,-107.037,65.911,-87.12,47.646, -109.21,47.916,-98.087,11,11,11,11,11,11,11,11,11,11,11,11,11,0,'CPI' 8. Data Organization 8.1 Data Granularity The smallest unit of data for the level-2 GOES-7 SW/LW imagery is a series of SW or LW images for a given day. 8.2 Data Format(s) The data file contain numerical and character fields of varying length separated by commas. The character fields are enclosed with single apostrophe marks. There are no spaces between the fields. A complete day of SW and LW data is contained in several SW files and one LW file. The storage format/arrangement of the data is due to the manner in which the SW and LW components were derived and delivered by FSU. Each SW file contains all the SW parameter images for one 30-minute period. The SW file contains 49 records of 8192 bytes. Each SW parameter image contains 128 2-byte pixel values in each of the 128 lines and is stored in four data file records (i.e., 128 * 2 * 128 = 32,768 and 32,768/4 = 8,192). The series of records in the SW file is: Record Number Content Storage format ------------- -------------------------- --------------------------- 01 Header Record (128 ASCII Characters/Line) 02-05 Scaled Visible Reflectance (16 bit integers) 06-09 Scaled Water Vapor (16 bit integers) 10-13 Scaled TOA Down (16 bit integers) 14-17 Scaled NB TOA Albedo (16 bit integers) 18-21 Scaled NB Cloud Albedo (16 bit integers) 22-25 Scaled NB Minimum Albedo (16 bit integers) 26-29 Scaled SW Down (16 bit integers) 30-33 Scaled SW Up (16 bit integers) 34-37 Scaled Surface Albedo (16 bit integers) 38-41 Scaled PAR Down (16 bit integers) 42-45 Scaled PAR Up (16 bit integers) 46-49 Scaled PAR Albedo (16 bit integers) Each LW file contains all the LW parameter images delivered for a given day. The LW files contain 105 records of 8,192 bytes each (105 * 8,192 = 860,160 bytes per file), one record (8,192 bytes) for the header, and four records for each of 26 images, equaling a total of 104 records of image data. Each LW parameter image contains 128 2-byte pixel values in each of the 128 lines, stored in four 8,192-byte records (128 samples * 2 bytes * 128 lines = 32,768 bytes, and 32,768/4 = 8192). The series of records in the LW file are: Record Number Content Storage format ------------- -------------------------- --------------------------- 01 Header Record (128 ASCII Characters/Line) 002-005 Image for 1300 UTC (16 bit integers) 006-009 Image for 1330 UTC (16 bit integers) 010-013 Image for 1400 UTC (16 bit integers) 014-017 Image for 1430 UTC (16 bit integers) 018-021 Image for 1500 UTC (16 bit integers) 022-025 Image for 1530 UTC (16 bit integers) 026-029 Image for 1600 UTC (16 bit integers) 030-033 Image for 1630 UTC (16 bit integers) 034-037 Image for 1700 UTC (16 bit integers) 038-041 Image for 1730 UTC (16 bit integers) 042-045 Image for 1800 UTC (16 bit integers) 046-049 Image for 1830 UTC (16 bit integers) 050-053 Image for 1900 UTC (16 bit integers) 054-057 Image for 1930 UTC (16 bit integers) 058-061 Image for 2000 UTC (16 bit integers) 062-065 Image for 2030 UTC (16 bit integers) 066-069 Image for 2100 UTC (16 bit integers) 070-073 Image for 2130 UTC (16 bit integers) 074-077 Image for 2200 UTC (16 bit integers) 078-081 Image for 2230 UTC (16 bit integers) 082-085 Image for 2300 UTC (16 bit integers) 086-089 Image for 2330 UTC (16 bit integers) 090-093 Image for 0000 UTC (next day) (16 bit integers) 094-097 Image for 0030 UTC (next day) (16 bit integers) 098-101 Image for 0100 UTC (next day) (16 bit integers) 102-105 Image for 0130 UTC (next day) (16 bit integers)