Development of an Airborne Sea Ice Thickness Measurement System and Field Test Results

• Main Authors: Kovacs, Austin, Holladay, J. S.
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
• Format: Text
• Language: English
• Published: 1989
• Subjects: Snow; Ice and Permafrost; Electricity and Magnetism; *SOUNDING; *SEA ICE; MEASUREMENT; THICKNESS; ELECTROMAGNETIC PROPERTIES; AIRBORNE; FIELD TESTS; STRENGTH(MECHANICS); DRIFT; ELECTROMAGNETIC INDUCTION; HELICOPTERS; PRESSURE; NOISE; ASSEMBLY; AIRCRAFT ANTENNAS; ELECTRICAL MEASUREMENT; ARCTIC REGIONS; RIDGES; TOWED BODIES; MATHEMATICAL MODELS; ALGORITHMS; ICE FLOES; PRESSURE RIDGE KEELS; Arctic; Ice; permafrost; Sea ice
• Online Access: http://www.dtic.mil/docs/citations/ADA224867; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA224867

Recent efforts to improve airborne electromagnetic induction- measurement technology and to downsize the related helicopter-towed antenna assembly from about 7.5 m long to about 3.5 m long for use in airborne measurement of sea ice thickness are discussed, as are the results from arctic field testing. Also outlined are the system noise and drift problems encountered during arctic field evaluation, problems that adversely affected the quality of the sounding data. The sea ice sounding results indicate that it should be possible to determine thickness to within 5% for ice floes with moderate relief but that, because of sounding footprint size and current model algorithm constraints, steepsided pressure ridge keels cannot be well defined. The findings also indicate that routine sea ice thickness profiling from an airborne platform is close at hand with further system improvement, as is the apparent capability to determine the conductivity of the sea ice, from which an assessment of sea ice strength can be made. Keywords: Airborne profiling; Electromagnetic induction measurement technology; Sea ice thickness.