Retrieval of sea ice thickness distribution in the seasonal ice zone from air-borne L-band SAR

• Published in: International Journal of Remote Sensing
• Main Authors: Toyota, T., Nakamura, K., Uto, S., Ohshima, K. I., Ebuchi, N.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Taylor & Francis
• Subjects: Sea ice; Ice thickness; L-band synthetic aperture radar (SAR); Topography; Surface roughness; Seasonal ice zone; 452; Okhotsk; Icebreaker
• Online Access: http://hdl.handle.net/2115/43124; https://doi.org/10.1080/01431160802558790

Although it is known that satellite data are useful for obtaining ice thickness distribution for perennial sea ice or in stable thin sea ice areas, it is still an unresolved issue for the seasonal sea ice zone (SIZ). In this study, we approach the problem of ice thickness retrieval by using L-band Synthetic Aperture Radar (SAR). In the SIZ, ice thickness growth is closely related to the ridging activity and therefore surface roughness is expected to be correlated with ice thickness. L-band SAR is suitable for detecting such surface roughness, and therefore is expected to be a good tool for obtaining thickness distribution. To verify this idea, we conducted ship-borne electromagnetic (EM) inductive sounding and supersonic profiling observations with an icebreaker, coordinated with airborne L-band SAR observations in the southern Sea of Okhotsk in February 2005. The surface elevation was estimated by representing the ship's motion with a low-pass filter. Backscattering coefficients correlated well with ice thickness and surface roughness, defined by standard deviation of surface elevation. This result sheds light on the possibility of determining ice thickness distribution in the SIZ.