K-Axis voyage of the Aurora Australis, 2015-16 season - Kerguelen Axis Marine Science parent metadata record

Brief description

The Kerguelen Axis voyage was planned to collect data to enhance the realism of end-to-end ecosystem models being developed in the Antarctic Climate and Ecosystems Cooperative Research Centre, to investigate the effects of climate change and ocean acidification on Southern Ocean ecosystems in the Indian Sector (particularly in relation to factors affecting the northern distribution of Antarctic krill) and to contribute to assessment of the spatial relationship of mesopelagic mid-trophic level species, in particular zooplanktivores, to foraging strategies by marine mammals and birds on the Kerguelen Plateau.

Nine projects were undertaken aboard the Aurora Australis. Each project had individual objectives and outputs, and there are metadata records for each data set collected. They were designed to be complementary in order that the whole data set and project analyses could be used to address the objectives of the Kerguelen Axis program. Observations will be contributed to the Southern Ocean Observing System (SOOS) and will facilitate the design of future ecosystem observing in the region.

Lineage

Progress Code: onGoing

Statement: See the child records for further information

Generally, the K-Axis marine science voyage met science goals. Some on-board experiments were terminated early due to the grounding of the vessel at Mawson Station in late February 2016 and scientific sampling was also halted at this time.

Notes

Purpose
Complimentary studies were designed to investigate: i) the key physical and biological drivers of Antarctic krill distribution, including factors that determine its northern limits, that can be used in ecosystem models aimed at investigating the dynamics of the krill-based food web and how this may be impacted by climate change and ocean acidification on Southern Ocean ecosystem; ii) the relative importance of different sources of iron to primary production on the Kerguelen Axis, notably the difference between supply from the shallow plateau with and without islands compared to areas of open ocean, and how this affects the composition of phytoplankton assemblages and production and the consequent effects on zooplankton. This will provide for correct representation and parameterisation in ecosystem models of many key lower trophic species in the Indian Sector; iii) change in the oceanography of the Indian Sector of the Southern Ocean based on repeat measurements of Antarctic Bottom Water (AABW); iv) the relationship between myctophid fish, zooplankton and oceanographic features of the region of BANZARE Bank and the northern Kerguelen Plateau; ii) the potential for the spatial distribution of mesopelagic fish to determine the foraging hotspots of marine mammals and birds in the region; iii) implementation and evaluation of size-structured fish-based food web models for the northern Kerguelen Plateau as well as of a regional application of the mesopelagic fish model within the ecosystem model, SEAPODYM.