Autosub Under Ice
Background
Exploring the least-accessible ecosystem on Earth
Autosub is a 7m long torpedo-shaped submersible robot that can venture under floating ice, the last great unexplored region on our planet. Ice plays a crucial role in our climate system. Researchers particularly want to know what might happen if polar ice melts.
A few kilometres out, Autosub loses contact with its mother ship, and is as remote and inaccessible as any spacecraft.
In 2005, Autosub explored 25km under an ice sheet, the Fimbulisen Glacier in Antarctica. This mission was the Autosub Under Ice programme's equivalent of a moon landing, and, in 27 hours, gathered data on ice thickness and shape that conventional drilling could have taken hundreds of thousands of years to collect.
Researchers need to know the shape and thickness of floating ice to understand its complex melting and refreezing. Before Autosub's mission under the Fimbulisen Glacier, there was no good information.
During the 5-year research programme, Autosub also explored under sea ice around Greenland, taking millions of thickness measurements, revealing new seabed features, and discovering a new ocean current.
Near the Kangerdlugssuaq Fjord system, in south east Greenland, researchers used Autosub to build up a three-dimensional map of the seabed, showing the distinctive tracks of icebergs grounding and dragging along the seabed.
Other researchers measured salinity levels and took water samples. Their work confirmed that glaciers were contributing massive amounts of freshwater to the fjord.
Unfortunately, Autosub didn't return from the last planned mission of the programme, in Antarctica. The programme had always recognised that the risk of losing Autosub under polar ice was about 50% for each mission. But a replacement was quickly built, and in summer 2005 it became part of the national marine equipment pool, available to scientists across the UK.
Engineers at the National Oceanography Centre, Southampton, are now building a deep-water version, Autosub 6000, which should be ready for trials in 2008.
The Autosub science missions programme
The Autosub Science Missions programme preceded the Autosub under ice programme, running from financial year 1997/8 to 2001/2. NERC invested £2.6m in the programme, which amongst other research, investigated how the bubbles in breaking waves can be used to understand turbulence, how fish respond to ship noise, how water is channelled from one ocean basin to another, and how chemicals such as manganese are distributed on the floor of sea lochs.
Design award
Autosub was awarded Millennium Product status by the UK Design Council.
Autosub and industry
In 2001 Autosub's design was licensed to Halliburton Subsea for use in the oil, gas and subsea cable markets.