Radar Interferometric Possibilities for Determining Sea Ice Thickness

Tuesday, 16 December 2014
Scott Hensley1, Benjamin Holt1, Sermsak Jaruwatanadilok2, Jeff Steward2, Shadi Oveisgharan2, Delwyn Moller3, Andrew R Mahoney4 and Jim Reis5, (1)NASA Jet Propulsion Laboratory, Pasadena, CA, United States, (2)Jet Propulsion Laboratory, Pasadena, CA, United States, (3)Remote Sensing Solutions, Inc., Sierra Madre, CA, United States, (4)University of Alaska Fairbanks, Fairbanks, AK, United States, (5)Fugro Earthdata International, Frederic, MD, United States
Sea ice thickness is a primary indicator of climate change in the polar oceans, as the thickness is a time-integrated result of both thermodynamic and dynamic processes. The large-scale ocean and atmospheric forcing acts on the fine-scale (a few to 10s of meters) opening and closing of the sea ice cover along fractures. The mean thickness and variance of sea thickness at km scales (50 cm uncertainty) are derived from recent spaceborne observations from the ICESat lidar and in the Arctic from sporadic upward looking sonar measurements. However, accurate measurements of sea ice thickness at the fine-scales at which the forcing is occurring are virtually non-existent.

In this paper we explore two potential radar interferometric means of obtaining sea ice thickness. One method uses high frequency Ka-band (8.5 mm wavelength) to infer sea ice thickness by measuring elevations to the surface of the ice and to the ocean surface in nearby open leads. Data from the NASA Glistin radar is used to illustrate this methodology. Alternatively, we consider the use of dual frequency X-band and P-band (3 cm and 85 cm wavelengths) to exploit the differential penetration of longer versus shorter wavelength to estimate sea ice thickness. This technique is illustrated with data collected by the Furgo Earthdata GeoSAR system.

Portions of this research were conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.