Airborne-deployed ocean sensors in the Southern Ocean, 2016-2018, Level 0 data

Brief description

Extracted Level 0 data are provided as audio files recorded in flight with a Sony PX470 voice recorder. These files were processed to generate the associated Level 2 products.

Project 4346 demonstrated the use of Airborne eXpendable Bathy-Thermograph (AXBT) and Airborne eXpendable Conductivity, Temperature, Depth (AXCTD) sensors from a BT-67 Basler aircraft in East Antarctica. The primary objective was to use AXBT and AXCTD sensors to infer seafloor depth where no previous measurements had been made by ship, often by deploying sensors into narrow gaps in sea ice. Inferring a snapshot of the ocean state by detecting major thermoclines was a secondary objective.

Although several sensors were purchased with external funds, the efforts to develop operational and subsequent data analysis approaches were unfunded as this was an add-on, target of opportunity. The effort is best described as a prototype demonstration project to test whether the seafloor depth could be inferred beneath narrow sea ice leads from a rapidly flying aircraft. All but eight AXBT sensors were donated to the University of Texas Institute for Geophysics (UTIG); AXCTDs were purchased by the Antarctic Gateway Partnership. Receiver and data processing equipment were loaned to UTIG.

Lineage

Progress Code: completed

Statement: The vast majority of AXBT and AXCTD sensors successfully transmitted signals to the aircraft; however, a handful of sensors either did not transmit or transmitted noisy and likely uninterpretable data.
An ongoing analysis effort attempts to increase confidence in the seafloor impact signal and the proper equations to use for depth, temperature, and salinity calculations. An update to this metadata record will be submitted when this analysis is completed.