BAMOS Vol 31 Special Issue October 2018 Bulletin Vol 31 Special Issue 01 2018 | Page 19

BAMOS
Special Issue
Influences from the Far South—
Antarctica and Australia
Tas van Ommen
Australian Antarctic Division
Antarctica and the Southern Ocean have a profound influence
on global weather and climate, and ice cores from Antarctica
tell the story of this influence on timescales up to hundreds of
millennia (Figure 1).
Of the many profound findings to emerge from Antarctic ice core
science, the most remarkable is the amazingly tight coupling
seen between Antarctic temperature and global atmospheric
carbon dioxide. This finding has shaped our thinking about
the workings of the climate system, the relationships between
climate forcing and glacial cycles. It has placed Antarctica and
particularly Southern Ocean processes at the centre of our focus
in understanding long-term climate evolution.
We are now in a very interesting time, as we face pressing issues
of understanding climate change, where the ice of Antarctica
is delivering much needed information that the early pioneers
could not have envisioned. Ice core studies have given us
insights into the drivers of Australian climate and drought that
extend our knowledge from the short instrumental period to
now covering thousands of years. In fact, Australia is now a part
of a major international push to take the ice core record back to
its limit in Antarctica to recover a core over a million years old.
This will provide critical information on drivers of glacial cycles
that current records cannot reach.
Of course, such issues were not at the front of mind for early
Antarctic explorers, although they were aware that influences
from the far south play an important role in Australian weather
and climate. Indeed statements about Antarctica and Australian
weather were made by early explorers such as Sir Edgeworth
David and Australian politicians including Lord Richard Casey.
Figure 1. Temperature and CO 2 concentrations over the past 800 thousand years from ice core studies.
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