The RAN Australian Hydrographic Service conducted an airborne hydrographic survey LADSII at Macquarie Island, February to March 1999. The areas surveyed included the northern coast between Handspike Point and Garden Bay and an area in the vicinity of Judge and Clerk Islets north of Macquarie Island. The survey dataset, which includes metadata, was provided to the Australian Antarctic Data Centre by the Australian Hydrographic Office and is available for download from a Related URL in this metadata record. The survey was lead by M.J.Sinclair. These data are not suitable for navigation.

Metadata record for data from ASAC Project 1342 See 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 day TIME is in seconds after midnight (UTC). LASER is the laser altitude above the snow/ice (metres). A zero reading indicates 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. SITE LATITUDE LONGITUDE SNOW THICKNESS ICE THICKNESS FREEBOARD a is the electrode spacing. R is the measured resistance. Rho is the apparent conductivity (not true conductivity) = 2 aR. CONDUCTIVITY = 1/Rho.