Activities of the training vessel Umitaka-maru (KARE16 ; UM-12-08) of the Tokyo University of Marine Science and Technology during the 54th Japanese Antarctic Research Expedition in 2012/2013

Abstract

A marine science cruise was undertaken in the Indian sector of the Southern Ocean during the 2012/2013 austral summer on the training vessel Umitaka-maru (KARE16; UM-12-08) of the Tokyo University of Marine Science and Technology (TUMSAT). A primary aim of the cruise was to carry out a TUMSAT and National Institute of Polar Research (NIPR) collaborative project commissioned by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), entitled“Japanese Antarctic Research Expedition (JARE) Routine Observation: Physical and Chemical Oceanography”. In addition to the MEXT-commissioned project, two TUMSAT-NIPR collaborative projects were conducted: 1)“Studies on Plankton Community Structure and Environment Parameters in the Southern Ocean”, which is one of the original research projects of the JARE phase VIII (JAREs-52 to -57) projects; and 2)“Environment and Ecosystem Changes in the Southern Ocean”. The Umitaka-maru departed from Fremantle, Australia, on 31 December 2012, sailed to the study area situated along 110°E in the marginal sea ice zone, and returned to Hobart, Australia, on 24 January 2013. Detailed properties of the Antarctic bottom water were revealed from physical and chemical oceanographic observations collected using a conductivity-temperature-depth profiler deployed to near the seafloor in the marginal ice zone. In addition, participants performed various net castings to qualitatively evaluate the vertical distribution of plankton communities, and deployed two year-round mooring arrays to assess the dynamics of Antarctic bottom water.