[IIOE-EP06] A coupled bio-physical, ecosystem-scale, examination of Australia's International Indian Ocean Expedition line (110°E)

Cruise No. EP06-1

Period of Cruise: 14 May, 2019 - 14 June, 2019

Chief Scientist: Professor Lynnath Beckley (Murdoch University)  


  • The 110°E voyage is Australia's main contribution to the IIOE-2 which currently has 30 countries involved with 16 voyages already completed
  • Voyage IN2019_V03 is a repeat of the 110°E meridional line last visited in 1963 when HMAS Diamantina visited oceanographic stations on voyages undertaken every six weeks for a year
  • Voyage IN2019_V03 will visit 20 stations, 90 nautical miles (167 km) apart along 110°E

Objectives of the voyage:
1) Quantification of multi-decadal, ecosystem-scale change from the 1960's benchmark in the physical, chemical and biological properties of the water column along 110oE;
2) Characterization of the physical and biological sources of nitrogen to the region and their impacts on regional biogeochemistry and ecology (microbes and genomics);
3) Determination of trophic relationships between nitrogen-fuelled primary production and zooplankton, including the larvae of mesopelagic fishes (food web);
4) Relating field information on phytoplankton community composition, primary production and carbon export to bio-optical quantities derivable from satellite ocean colour radiometry.

These objectives will be achieved via deployment of the instrumented CTD and rosette of 35 Niskin bottles, optics equipment, various profilers and a variety of different nets for plankton. Numerous onboard filtration activities as well as incubations and experiments will be conducted.

Additional Activities:

  • Acoustic surveys for CWR & Department of Defence
  • Towing of an IMOS Continuous Plankton Recorder
  • Deployment of 14 drifting weather buoys for Australian Bureau of Meteorology & USA National Oceanic & Atmospheric Administration
  • Deployment of one Argo profiling float for IMOS
  • Deployment of two Apex deep Argo floats for JAMSTEC
  • Towing of the Triaxus undulating profiler to examine oceanographic fronts on return journey