A comparison of sea-ice thickness measurements made using ship-mounted and airborne electromagnetic induction devices

Metadata record for data from ASAC Project 1342See the link below for public details on this project.---- Public Summary from Project ----This project involves field trialling of software written as part of ASAC project 1212 (2000-2001) to determine sea-ice thickness in real-time from ship-borne electromagnetic induction measurements. Computer simulation of ship- and helicopter-borne electromagnetic induction measurements over realistic sea-ice structures will also be performed in order to assess the suitability and cost-effectiveness of helicopter-mounted systems for future Antarctic sea-ice thickness measurements.Equipment used in this study were the IBEO PS100 infrared laser altimeter and the Geonics EM31 geophysical electromagnetic induction device.The fields in this dataset are:DAY is Julian dayTIME is in seconds after midnight (UTC).LASER is the laser altitude above the snow/ice (metres). A zero readingindicates no return (open water).PITCH is pitch of the system in degrees.ROLL is roll of the system in degrees.COND-A is analogue conductivity from the EM31 (not used).PHASE-A is analogue in-phase response from the EM31 (not used).COND is the estimated depth to seawater (metres) from the EM31-ICE processing module.PHASE is the EM31 in-phase response (expressed as parts per thousand of the primary field). A value of 9.99 indicates the magnetic field was too large to be recorded.SITELATITUDELONGITUDESNOW THICKNESSICE THICKNESSFREEBOARDa is the electrode spacing.R is the measured resistance.Rho is the apparent conductivity (not true conductivity) = 2 aR.CONDUCTIVITY = 1/Rho.