HR: 09:45h
AN: C41A-08    [PDF]
TI: The sea ice Thickness Distribution and Iceberg Size Distribution From AUV Measurements in the Northern Weddell and Eastern Amundsen Seas
AU: * Brandon, M A
EM: m.a.brandon@open.ac.uk
AF: The Open University, Department of Earth Sciences Walton Hall, Milton Keynes, MK7 6AA United Kingdom
AU: Brierley, A S
AF: Gatty Marine Laboratory, University of St Andrews, Fife, KY16 8LB United Kingdom
AU: Fernandes, P G
AF: FRS Marine Laboratory Aberdeen, PO Box 101 Victoria Road, Aberdeen, AB11 9DB United Kingdom
AU: Banks, C J
AF: The Open University, Department of Earth Sciences Walton Hall, Milton Keynes, MK7 6AA United Kingdom
AU: Jenkins, A
AF: British Antarctic Survey, High Cross Madingley Road, Cambridge, CB3 0ET United Kingdom
AU: Hayes, D
AF: British Antarctic Survey, High Cross Madingley Road, Cambridge, CB3 0ET United Kingdom
AU: Autosub Engineering Team, .
AF: Southampton Oceanography Centre, Empress Dock, Southampton, SO14 3ZH United Kingdom
AB: The AUV AUTOSUB 2 has been used on two campaigns in Antarctica. The first was in February 2000 at the northern edge of the Weddell Sea (~63S, 50W), the second in March 2003 at the shelf break region of Pine Island Bay (~71S, 102W). The aim in both cases for this project was to determine the sea ice thickness distribution on scales of 10's of km. In the first campaign the AUV was sent on missions of up to 80 km length at depths in the range 150-250 m. It was equipped with an upward looking scientific echo sounder operating at two frequencies as well as a full suite of oceanographic sensors including 2 CTD's, and both upward and downward looking ADCP's. The data allow derivation of the sea ice distribution and iceberg size distribution as well as recording under ice hydrographic data at very high spatial scales. We will show examples of the thickness data and give an example of the hydrographic data from a close approach to a small iceberg. In the second campaign the vehicle was substantially different and thickness data were obtained from upward looking ADCP data with shorter missions (~30 km) but at shallower depths. In total the AUV has collected over 500 km of data for this project and is part of the Autosub Under Ice programme. The AUV will be sent to the Greenland Sea in 2003 and then back to Antarctica in 2004/5 for missions beneath the Filchner Ronne ice shelf.
DE: 1635 Oceans (4203)
DE: 4207 Arctic and Antarctic oceanography
DE: 4536 Hydrography
DE: 4540 Ice mechanics and air/sea/ice exchange processes
DE: 4572 Upper ocean processes
SC: Cryosphere [C]
MN: 2003 Fall Meeting