[MIS15-P02] Inflows of offshore-origin warm water toward Totten Ice Shelf region, East Antarctica
Keywords:offshore warm water, eddy transport , ice-ocean interaction, Totten Ice Shelf, East Antarctica
In this presentation, we show the characteristics of offshore-origin warm water distribution at the TIS ice front and continental slope regions, using the hydrographic data obtained by Icebreaker Shirase in March 2018 (59th Japanese Antarctic Research Expedition) and R/V Kaiyo-maru in February 2019 (multidisciplinary ecosystem survey in the eastern Indian sector of the Antarctic with a focus on Antarctic krill, Fisheries Agency). The offshore-origin modified Circumpolar Deep Water (mCDW, up to 0.3oC) is found in deep glacial troughs near the TIS ice front, which is ~0.7oC warmer than that observed at the almost same position in January 2015 (Rintoul et al., 2016). This suggests a seasonal or interannual variation in inflowing ocean heat flux into TIS cavity. Along the continental slope, warmer mCDW (>1oC) lies at subsurface layer (~300-500 dbar), and particularly warm cores (1.2-1.4oC) is found around the eastern limb of cyclonic eddies, indicating a possible role of cyclonic eddies on a poleward transport of offshore warm water. Various processes from offshore to ice front regions would consequently result in the variations in the ocean heat flux into TIS cavity (i.e., the magnitude of basal melting) with various time scales.