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  • This dataset contains time-series of current profiles from beneath the Amery Ice Shelf obtained from an Acoustic Doppler Current Profiler (ADCP) (RDI 300 kHz broadband Workhorse) on the AM06 mooring string. The ADCP was positioned ~108 m below the base of the ice shelf and oriented to look upwards (i.e. toward the base of the shelf) to examine the water cavity boundary layer and the range (distance) from the instrument to the ice-ocean interface. Accounting for instrument displacement by ocean currents, changes in range are expected to be indicative of basal melting. The dataset contains ~1 year of velocity data from 07/01/2010 sampled at 30 minute intervals. In the vertical, the ADCP sampled 27 bins, with a measurement every 4m. Key variables in the dataset include ocean velocity (u, v, w), instrument orientation (pitch, roll, heading) and distance from the instrument to the ice shelf base (btdistance), as well as quality control parameters such as beam correlation (avbeamcor), strength of the return/echo amplitude (ampav) and velocity error (errv). Two data files are archived here, the raw data "adcp_am06_1noqc.nc" and the quality-controlled data "adcp_am06_1qc.nc". Descriptions of the quality control and post-processing are found in "readme.rtf" and notes and preliminary plots are found in "borehole2010_11.pdf".

  • This dataset contains ice motion observations made under the Australian Antarctic Program, Projects 4593 and 4506. Measurements of ice motion where made on (land)fast ice on the eastern rim of the Amery Ice Shelf, Antarctica (69.2 degr. S, 76.3 degr. E) and on landfast ice in Gronfjorden, Svalbard (78.0 degr. N, 14.2 degr. E). Data was obtained using Spotter wave buoys (Sofar Ocean Technologies), hereafter wave buoys, and open-source ice motion loggers, hereafter ice buoys. Instrumentation was deployed on top of the sea ice with the main motivation to measure its vertical motion due to ocean waves. The wave buoys 3-axis measure motion at 2.5 Hz through GPS and have an accuracy of approximately 2 cm for the significant wave height. The ice buoys measure motion in 9-degrees-of-freedom at 10Hz using a VectorNAV VN-100 IMU, accuracy is O(mm) for short waves and O(cm) for long waves. Both instruments also record their geographical location through GPS. Full time series of their motion is processed on board and summaries are send through Iridium. For the wave buoy, this occurred at an interval of 30 minutes. For the ice buoy this occurred every 3 hours. In the dataset, WB and IB are abbreviations for wave buoy and ice buoy, respectively. This dataset covers 2-8 January 2020 for the Antarctic campaign (WB1, WB2, IB1, IB2) and 14-28 March for the Arctic campaign (IB3, IB4, IB5) and includes significant wave height, peak period and the geographical coordinates of the instrumentation. ‘Hs’ refers to significant wave height (in meters). ‘Tp’ refers to peak period (in seconds). Time is in UTC, and in Matlab’s datenum format (i.e. the number of days since year 0000). The geographical coordinates ‘lat’ and ‘lon’ (latitude and longitude, respectively) are in degrees. Note, as the ice buoys transmit the GPS coordinates and wave data in separate data messages, for the ice buoys ‘time’ refers to the reference time of the wave properties Hs and Tp, whereas ‘time_latlon’ refers to the reference time of the geographical coordinates. For the wave buoy, all data is transmitted in one message.

  • Oceanographic measurements were conducted in the vicinity of the Amery Ice Shelf on two cruises, during the southern summers of 2000/2001 and 2001/2002. A CTD transect parallel to the front of the Amery Ice Shelf was occupied on both cruises, including repeat occupations on each cruise. A total of 100 CTD vertical profile stations were taken near the ice shelf, most to within 20 m of the bottom, and over 1150 Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients, helium, tritium, oxygen 18 and biological parameters, using a 12 bottle rosette sampler mounted on either a 24 or 12 bottle frame. On the first cruise, an additional 39 CTD stations were occupied around an experimental krill survey area in the vicinity of Mawson. Additional CTD stations were taken at the end of each cruise for calibration of CTD instrumentation from borehole sites on the Amery Ice Shelf. Near surface current data were collected on both cruises using a ship mounted ADCP. An array of 9 moorings comprising current meters, thermosalinographs and upward looking sonars were deployed along the ice shelf front in February 2001 during the first cruise, and retrieved on the second cruise in February 2002. A summary of all data and data quality is presented in the data report.