Possibility of AABW source originating from meddle size polynyas along the coast of Australian-Antarctic Basin
Abstract
Antarctic Bottom Water (AABW) is the densest water in the ocean and globally significant; its production at the Antarctic margin is a key component of the global overturning circulation [eg. Marshall and Speer, 2012]. AABW originating from a middle size polynya called Vincennes Bay Polynya (VBP) was discovered recently [Kitade et al., 2014]. The fact that a middle size polynya can be a formation site of AABW suggests the possibility that the unknown formation area further exists along the coast of Australian-Antarctic Basin. A deep profiling float, called "Deep NINJA" which is able to observe temperature and salinity at depths up to 4,000 m, was developed by Japan Agency for Marine-Earth Science and Technology and Tsurumi-Seiki Co. [Kobayashi et al., 2015]. Five deep floats were deployed along 110oE in Jan. 2014. One of them drifted west almost along the continental rise and has been observing 40 profiles within two years. However, no signal of newly formed AABW has been observed except in the region off VBP, which is consistent with the BROKE results [eg. Bindoff et al., 2000) and our analysis result of BROKE data. Although these observations do not completely negate the additional formation of AABW originating from middle size polynyas located west of VBP, their formation volume of AABW is suggested to be much smaller than that from VBP.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFMOS31A1999K
- Keywords:
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- 4894 Instruments;
- sensors;
- and techniques;
- OCEANOGRAPHY: BIOLOGICAL AND CHEMICALDE: 4215 Climate and interannual variability;
- OCEANOGRAPHY: GENERALDE: 4262 Ocean observing systems;
- OCEANOGRAPHY: GENERALDE: 4273 Physical and biogeochemical interactions;
- OCEANOGRAPHY: GENERAL