NEW light鈥攁lmost certainly ultra-violet (UV)鈥攚as shed on
Antarctica by two award-winning presentations in the Fresh Science programme in
Melbourne last week. We learned that about 30 million years ago Antarctica was
splitting in two with potentially disastrous present-day consequences, and also
that the small but important marine creatures in southern waters called krill
may be able to resist the debilitating effects of extra UV light passing through
the ozone 鈥渉ole鈥�.
Fresh Science, which gathers together 16 of Australia鈥檚 best and brightest
young researchers to present new work that has had little or no publicity, is a
highlight of ScienceNOW! the national science forum. The man who cracked
Antarctica, Dietmar M眉ller of the University of Sydney, won a scientific
visit to the UK courtesy of the British Council when the judges decided his
presentation was the best of the series. His Antarctic colleague, Stuart Newman,
was highly commended.
M眉ller鈥檚 ground-breaking work involved mapping the floor of the Southern
Ocean and the underlying rock near Antarctica. North of the Ross Sea, he found a
small ocean basin about 200 kilometres wide, which formed when east and west
Antarctica split apart. Molten rock flowed out of a rift in the Earth鈥檚 crust,
cooling to form a new section of sea bed. The work has just been published in
the weekly UK science journal, Nature (vol 404, p 145).
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M眉ller鈥檚 findings are not just interesting facts, they back up the view
that the North Island of New Zealand is part of the Australian plate and the
South Island part of the Pacific plate, and that continuing movement between the
two plates is the underlying cause of the seismic instability of the Shaky
Isles. Around Antarctica, movement between the plates which are a legacy of the
split could cause tsunamis which threaten Tasmania.
The disaster warnings at least were balanced by some reassuring news from the
far south. Many biologists have been worried because the ozone 鈥渉ole鈥� would
expose krill to increased levels of UV light, which has the potential to kill
them. These small shrimp-like crustaceans are found in enormous numbers around
Antarctica, where they form the basis of the diet of larger creatures: fish,
penguins, seals and even whales. They are vital to the entire Antarctic food
chain. A krill kill would have widespread flow-on effects.
Newman, however, reported that his research shows krill can avoid the
dangerous UV through a combination of diet and exercise. A research student in
zoology at the University of Tasmania, he found that krill have a capacity to
detect UV and swim away from the danger. Even more interesting is the fact that
some of the algae the krill eat are rich in compounds that act as natural
sunscreens. And the greater the level of UV, the more the algae produce these
compounds. So their diet gives the krill some protection, although the research
鈥渄oes not prove that krill are totally safe,鈥� Newman says. It does provide some
comfort, however.
Small innovations can have a big impact, especially on the domestic front.
Take the humble mixer tap, for instance, which many homes now use instead of
separate hot and cold taps.
The standard design incorporates a lever to vary the blend of hot and cold
water. When the lever points to the user, the mix is 50:50. Since most hot water
systems are set to heat water to a temperature that is too hot for comfort, that
position makes sense. But many people simply leave the setting there. So every
time they use the tap to supply cold water, a small amount of hot water is drawn
from the tank and cools in the pipe. That is very wasteful of energy and money,
since the consumer has paid for that water to be heated needlessly.
Now there is a new mixer tap on the market which delivers cold water with the
lever in the middle. To add hot water, you have to turn the lever to the left.
Melbourne energy consultant Alan Pears told me of the new device because he is
excited about the potential for savings. For years he has been using the example
of the mixer tap to highlight the stupidity of some designs. 鈥淚t will be nice to
be able to point people to a solution,鈥� he says.