Imaging Radar Observations of Frozen Arctic Lakes
1976; Elsevier BV; Volume: 5; Linguagem: Inglês
10.1016/0034-4257(76)90047-x
ISSN1879-0704
AutoresC. Elachi, Mark L. Bryan, W. F. Weeks,
Tópico(s)Cryospheric studies and observations
ResumoL-band radar images of a number of ice-covered lakes located approximately 48 km northwest of Bethel, Alaska show large differences-in radar backscatter with lakes showing homogeneous low-returns, homogeneous high-returns and/or low-returns around the lake borders and high-returns from the central areas. The patterns of the returns suggest that a low-return indicates that the lake is frozen completly to its bottom while a high-return indicates the presence of fresh-water between the ice cover and the lake bed. This interpretation is in good agreement with the limited information available on lake depths in the study area, and recent X-band radar observations of North Slope lakes by Sellman, Weeks and Campbell who suggested such an interpretation. These effects are, however, more striking in the L-band than in the X-band imagery. This can be explained by the fact that volume inhomogeneities, such as air bubbles, will cause more scattering and conductivity losses and thus more attenuation at the shorter wavelengths (X-band, 3 cm).
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