The evolution of Antarctic bottom water since the Last Glacial Maximum using optimum multiparameter analysis (OMP)

• Grant number: 13/20977-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: December 01, 2013
• End date: November 30, 2014
• Field of knowledge: Physical Sciences and Mathematics - Oceanography - Physical Oceanography
• Principal Investigator: Ilana Elazari Klein Coaracy Wainer
• Grantee: Juliana Marini Marson
• Supervisor: Lawrence A. Mysak
• Host Institution: Instituto Oceanográfico (IO). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: McGill University, Montreal, Canada
• Associated to the scholarship: 11/02047-9 - Meltwater pulses in the Last Glacial Maximum transition: impacts on physical and dynamical structure of Southern Ocean, BP.DR

Abstract

The Antarctic Bottom Water (AABW) is an important component on the ocean's global circulation, which is responsible by the heat distribution from equator to the Poles. The variability of AABW formation and export is, therefore, intimately associated with climate changes. This water mass is formed around Antarctica, where the surface waters are at freezing point and receive the brine rejected during sea ice formation. These two factors contribute to make the water dense enough to sink. Since the Last Glacial Maximum, the Southern Ocean has received a large amount of fresh water resulting from the melting of Antarctic Ice Sheet. The input of meltwater in the AABW formation points affects its production. Using the first transient simulation of the last 21,000 years, this study aims to determine the thermohaline changes in AABW and the variability in its spatial distribution driven by the incoming meltwater. We expect to see a reduced formation of a fresher and warmer AABW, especially after a large meltwater pulse that took place at ~14,000 years ago. (AU)