Alaska Satellite Facility - Distributed Active Archive Center

GISMO — Data Products

May 23, 2006, 150 MHz Data Products

Each flight line was segmented into approximately 25 km long sections with 20% overlap on each end. Each segment contains the following data in a zip file:

1. Thickness data 32 bit float binary, 10 m pixel resolution ‘seg#_thickness’
2. Thickness data GeoTIFF ‘seg#_thickness_geo.tif’
3. Thickness data graphic ‘seg#_thickness.gif’
4. Image data 32 bit float binary, 10 m pixel resolution ‘seg#_image’
5. Image data GeoTIFF ‘seg#_image_geo.tif’
6. Image data graphic ‘seg#_image.gif’
7. Header file with columns, rows, projection information, and corner map coordinates ‘seg#.hdr’
8. ASCII file with latitude, longitude, and aircraft altitude of corresponding segment ‘seg#_0_0.pos’ where the last two numbers represent waveform and channel. There are 4 waveforms and as many as 8 channels.

‘seg#’ refers to the segment number ie: 0_3, 3_7, 7_11 etc.

Products

Sept 10, 2007, 450 MHz Data Products

Each flight line was segmented into approximately 25 km long sections with 20% overlap on each end. Since there were only 4 channels for these data, good left-right separation was not possible, thus there is no image or thickness data available for 2007. The following is what is included in the product zip files:

1. ASCII file with latitude, longitude, and aircraft altitude of corresponding segment ‘seg#_0_0.pos’ where the last two numbers represent waveform and channel. There are 4 waveforms and as many as 8 channels.
2. 450 MHz (Sept 10) intensity data 32 bit float binary, 5X25 m (pixel x line) resolution which includes both the surface and base part. Slant range imagery can be used to get the nadir thickness information. ‘seg#_inten’
3. Azimuth compressed header file with column, row, resolution, wavelength, and # looks ‘seg#_0_0.azcom.par’
4. Azimuth compressed nadir file with latitude, longitude of first pixel of each azimuth line in the slant range image, aircraft altitude, and roll angle in degrees (last column) ‘seg#_0_0.azcom.nadir’
5. 450 MHz (Sept 10) Surface/Base profile gives an estimate (may not be exact in some areas) of the surface and the base profile. ‘seg#_surface_base.profile’ *note not all segments have this file*

Ice_elevation = (base_pixel – surface_pixel)*5.0/1.8 (m)

‘seg#’ refers to the segment number ie: 0_3, 3_7, 7_11, 100_110 etc.

GISMO – Schematic Labeling the Inbound and Outbound Flight Lines

Products

Sept 10, 2007, 450 MHz Outbound Flight Line A

Sept 10, 2007, 450 MHz Outbound Flight Line B

Sept 12, 2007, 150 MHz Data Products

Each flight line was segmented into approximately 25 km long sections with 20% overlap on each end. Since there were only 4 channels for these data, good left-right separation was not possible, thus there is no image or thickness data available. The following is what is included in the product zip files:

1. ASCII file with latitude, longitude, and aircraft altitude of corresponding segment ‘seg#_0_0.pos’
2. 150 MHz (Sept 12) Intensity data 32 bit float binary, 5X25 m (pixel x line) resolution which includes both the surface and base part. Slant range imagery can be used to get the nadir thickness information. ‘seg#_inten’
3. Azimuth compressed header file with column, row, resolution, wavelength, and # looks ‘seg#_0_0.azcom.par’
4. Azimuth compressed nadir file with latitude, longitude of first pixel of each azimuth line in the slant range image, aircraft altitude, and roll angle in degrees (last column) ‘seg#_0_0.azcom.nadir’
5. 150 MHz (Sept 10) Surface/Base profile gives an estimate (may not be exact in some areas) of the surface and the base profile. ‘seg#_surface_base.profile’

Ice_elevation = (base_pixel – surface_pixel)*5.0/1.8 (m)

6. Image, thickness, and header data for two segments 450_460 and 480_490 ‘seg#_image, seg#_thickness, and seg#.hdr’
7. Image and thickness GeoTIFF’s for segments 450_460 and 480_490 ‘seg#_image_geo.tif’ and ‘seg#_thickness_geo.tif’
8. Thickness data graphic for segments 450_460 and 480_490 ‘seg#.thickness.tiff’

‘seg#’ refers to the segment number ie: 0_3, 3_7, 7_11, 100_110 etc.

Products

Sept 12, 2007, 150 MHz Outbound Flight Line

Sept 12, 2007, 150 MHz Inbound Flight Line

2008 Low Aircraft Elevation Data Products

Each flight line was segmented into approximately 25 km long sections with 20% overlap on each end. Each segment contains the following data in a zip file:

1. Thickness data 32 bit float binary, 20 m pixel resolution ‘seg#_thickness’
2. Thickness data GeoTIFF, 20 m, ‘seg#_thickness_geo.tif’
3. Thickness data graphic ‘seg#.thickness.tiff’
4. Image data 32 bit float binary, 20 m pixel resolution ‘seg#_image’
5. Image data GeoTIFF, 20 m, ‘seg#_image_geo.tif’
6. Header file with columns, rows, projection information, and corner map coordinates ‘seg#.hdr’
7. ASCII file with latitude, longitude, and aircraft altitude of corresponding segment ‘seg#_0_0.pos’ where the last two numbers represent waveform and channel. There are 4 waveforms and as many as 8 channels.
8. Intensity graphic ‘seg#_inten.tif’ where the along track is in the vertical direction and the cross track (slant range) is in the horizontal direction from left to right. The brightest part on the left is the ice surface. There are discontinuities between the surface and the base resulting from different azimuth looks. Only two looks are used to create the surface portion (left) and 20 looks are used to create the base portion (right). The white line (right) represents the base and is an estimate of the nadir profile.

‘seg#’ refers to the segment number ie: 0_3, 3_7, 7_11 etc.

Example of intensity
 tif 310_320_inten.tif

Low aircraft elevation data and high elevation data overlap.
thick red line = high elevation
thin black dotted line = low aircraft elevation

Products

2008 High Aircraft Elevation Data Products

Each flight line was segmented into approximately 25km long sections with 20% overlap on each end. Each segment contains the following data in a zip file:

1. Elevation data 32 bit float binary, 20m pixel resolution ‘seg#_elevation’
2. Elevation data GEOtiff, 20m, ‘seg#_elevation_geo.tif’
3. Elevation data graphic ‘seg#.elevation.tiff’
4. Image data 32 bit float binary, 20m pixel resolution ‘seg#_image’
5. Image data GEOtiff, 20m, ‘seg#_image_geo.tif’
6. Header file with columns, rows, projection information, and corner map coordinates ‘seg#.hdr’
7. Base Intensity data 32 bit float binary, 5X25m (pixel x line) resolution which include both the surface and base part. This slant range image can be used to get the nadir elevation information and as a reference to the elevation maps. ‘seg#_base_inten’
8. Azimuth compressed header file with column, row, resolution, wavelength, and # looks ‘seg#_0_0.azcom.par’
9. Azimuth compressed nadir file with latitude, longitude of first pixel of each azimuth line in the slant range image and roll angle in degrees (last column) ‘seg#_0_0.azcom.nadir’
10. Surface/Base profile gives an estimate (may not be exact in some areas) of the surface and the base profile. ‘seg#_surface_base.profile’ *note: not all segments have this file*

Ice_thickness = (base_pixel – surface_pixel)*5.0/1.8(m)

‘seg#’ refers to the segment number ie: 0_3, 3_7, 7_11, 100_110 etc.

Low aircraft elevation data and high elevation data overlap.
thick red line = high elevation
thin black dotted line = low aircraft elevation

Products

2008 Southbound Flight Line

2008 Northbound Flight Line

products for segment 190_198 | 190_198.elevation.tiff
products for segment 198_205 | 198_205.elevation.tiff
products for segment 207_213 | 207_213.elevation.tiff
products for segment 271_281 | 271_281.elevation.tiff
products for segment 283_290 | 283_290.elevation.tiff

2008 Coastal Flight Line

products for segment 290_300 | 290_300.elevation.tiff
products for segment 300_310 | 300_310.elevation.tiff
no surface_base.profile file
products for segment 310_316 | 310_316.elevation.tiff
no surface_base.profile file