Oral Presentation AMOS Annual Meeting and International Conference on Tropical Meteorology and Oceanography

New, high resolution ice core records of the southern Indian Ocean (#200)

Tessa R Vance 1 , Nerilie J Abram 2 , Alison Criscitiello 3 , Mark A.J. Curran 4 , Vincent Favier 5 , Ailie J. E. Gallant 6 , Lenneke Jong 4 , Andrew Moy 4 , Joel Pedro 1 , Chris Plummer 1 , Jason L Roberts 4 , Paul Vallelonga 7 , Tas D van Ommen 4 , Danielle G Udy 1
  1. University of Tasmania, Battery Point, TAS, Australia
  2. Australian National University, Canberra, ACT, Australia
  3. University of Alberta, Edmonton, Alberta, Canada
  4. Australian Antarctic Division, Hobart, TAS, Australia
  5. University of Grenoble, Grenoble, France
  6. Monash University, Melbourne, Victoria
  7. Nihls Bohr Institute, Copenhagen, Denmark

Atmospheric circulation variability at decadal to centennial scales in the Southern Hemisphere mid- to high-latitudes is poorly understood. This is largely due to this region having very little in the way of habitable landmass, and as a result, understanding of how this region changes through time is primarily limited to the satellite era (1979-) and limited station data from sub-Antarctic islands and Antarctic research bases since 1958. This study details initial chemical and isotopic signatures at annual resolution over the observational era (1958-2017) from a new 295 m ice core drilled over the 2017-18 austral summer at a site called Mount Brown South in Wilhelm II land, East Antarctica. The site was chosen to fulfil a range of criteria, including to produce highly resolved (sub-annual) chemical and isotopic records spanning 1000-2000 years. The site is expected to be strongly teleconnected to the mid-latitude circulation of the southern Indian Ocean and to be complementary (ie, adds new rather than duplicating existing information) to the small existing East Antarctic ice core array covering the last 2000 years. Initial findings will be presented, including data that show clear annual cyclicity of chemical and isotopic signatures over 1958-2017, as well as volcanic sulphate signals (Agung, 1963 and Pinatubo, 1991).