University of Tasmania
Browse

File(s) under permanent embargo

Modelling dispersal of juvenile krill released from the Antarctic ice edge: ecosystem implications of ocean movement

Sea ice retreat is a key event affecting Southern Ocean ecosystems during spring and summer. The impacts of this change can be seen in these ecosystems from primary producers to top predators, through biological, chemical and physical systems. We apply a Lagrangian particle tracking method to investigate transport processes from the retreating sea ice edge in the Southern Ocean during spring and summer. The resulting distribution of surface krill patches is used as an case study for our modelling approach. Antarctic krill (Euphausia superba), a secondary producer, plays a key role in the Southern Ocean ecosystems. Antarctic krill are highly abundant in the Southern Ocean with a complex distribution pattern both in the horizontal and vertical dimensions. Observations dating back to the 1930s show that juvenile krill often form surface patches – high density clusters of krill at the ocean surface – throughout the Southern Ocean during the spring and summer seasons.

We develop a hypothesis, based on historical observations, that surface krill patches composed of juvenile krill move passively with ocean currents after their release from the sea ice edge zone in spring. Applying this hypothesis and method to the Southern Hemisphere spring/summer, leads to results that indicate that the observed changes in distribution of krill patches from historical to contemporary records could be related to the southward shift of the sea ice edge over the last century.

Funding

Australian Research Council

History

Publication title

Journal of Marine Systems

Volume

189

Pagination

50-61

ISSN

0924-7963

Department/School

Institute for Marine and Antarctic Studies

Publisher

Elsevier Science Bv

Place of publication

Po Box 211, Amsterdam, Netherlands, 1000 Ae

Rights statement

Crown Copyright © 2018 Published by Elsevier B.V.

Repository Status

  • Restricted

Socio-economic Objectives

Understanding climate change not elsewhere classified

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC