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Backscatter from ice growing on shallow tundra lakes near barrow, alaska, winter 1991-1992
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Morris, K. Jeffries, M. O. Wakabayashi, H. Weeks, W. F. |
| Copyright Year | 1993 |
| Description | The timing of freeze-up and break-up of Arctic lake ice is a potentially useful environmental indicator that could be monitored using SAR. In order to do this, it is important to understand how the properties and structure of the ice during its growth and decay affect radar backscatter and thus lake ice SAR signatures. The availability of radiometrically and geometrically calibrated digital SAR data time series from the Alaska SAR Facility has made it possible for the first time to quantify lake ice backscatter intensity (sigma(sup o)) variations. This has been done for ice growing on shallow tundra lakes near Barrow, NW Alaska, from initial growth in September 1991 until thawing and decay in June 1992. Field and laboratory observations and measurements of the lake ice were made in late April 1992. The field investigations of the coastal lakes near Barrow confirmed previous findings that, (1) ice frozen to the lake bottom had a dark signature in SAR images, indicating weak backscatter, while, (2) ice that was floating had a bright signature, indicating strong backscatter. At all sites, regardless of whether the ice was grounded or floating, there was a layer of clear, inclusion-free ice overlaying a layer of ice with dense concentrations of vertically oriented tubular bubbles. At some sites, there was a third layer of porous, snow-ice overlaying the clear ice. |
| File Size | 240910 |
| Page Count | 4 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19960003125 |
| Archival Resource Key | ark:/13960/t6k120p37 |
| Language | English |
| Publisher Date | 1993-07-29 |
| Access Restriction | Open |
| Subject Keyword | Earth Resources And Remote Sensing Lake Ice Backscattering Alaska Radar Signatures Ers-1 Esa Satellite Signature Analysis Environmental Monitoring Freezing Radar Imagery Arctic Regions Synthetic Aperture Radar Digital Data Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
