K043: Antarctic Sea Ice, Algal Productivity and Global Climate Change

Ken Ryan

Victoria University of Wellington

What we do: We aim to provide ground truth data of total primary productivity and biodiversity in Antarctic sea ice, and study the relationship between the extent of ice cover and total primary production along an extensive north-south transect of the western coast of the Ross Sea.

 

Why we do it: This study will be the first to assess the effect of global climate change on primary productivity in ice covered coastal ecosystems in the Ross Sea and will be used to predict future scenarios of reduced ice at southerly sites.

 

Some things we've found out so far: Several experiments on live algae and bacteria were carried out to determine their responses to the changes in salinity, temperature and light that they will encounter during the processes of ice formation at the start of winter and ice melting in summer.  Comparisons between bottom ice algae and those growing in brine within 30cm of the surface, showed distinctly different patterns of response to these treatments. Together, this information will enable us to describe the distribution and biodiversity of these organisms and to predict of the effect of future global warming on southern ocean ecosystems. This research contributes to the Latitudinal Gradient Project (LGP) and is an International Polar Year project.

Metadata and website links

The biomass, productivity and biodiversity of algae in the Cape Hallett region

The bacterial biomass of sea ice from Seabee Hook, Cape Hallett region

The biomass, productivity and biodiversity of algae and bacteria in Terra Nova Bay and the physical parameters of their environment

Algal response to transplantation with a ice core flipping experiment, Terra Nova Bay, Ross Sea

The role of grazing on sea ice algae and sea ice bacteria by ciliates and flagellated (zooplankton) in Terra Nova Bay

The response of sea ice and brine water algae and bacteria to changes in salinity, temperature, light and UVB in Terra Nova Bay

The distribution, taxonomy, physiology and feeding habits of pelagic amphipods in Terra Nova Bay

The biomass, productivity, physiology and grazing pressures of phytoplankton during the polar winter in the Ross Sea region

A mathematical model of population dynamics to explain changes in biodiversity of microorganisms in ice covered marine environments

The biomass, productivity and biodiversity of algae and bacteria in Granite Harbour and the physical parameters of their environment

The response of sea ice and brine water algae and bacteria to changes in salinity, temperature, light and UVB in Granite Harbour

The distribution, taxonomy,  physiology and feeding  habits of pelagic amphipods in the Ross Sea

Community composition survey at Terra Nova Bay with similar samples collected at Cape Evans and Cape Armitage

Trace metal analysis of sea ice at Granite Harbour

Ken's webpage