APRIL 2003 EDITORIAL
I
love a sunburnt country,
A land of sweeping plains,
Of ragged mountain ranges,
Of droughts and flooding rains...
So goes the poem by Dorothea Mackellar. But do we really love
those droughts, which inevitably give way to flooding rains?
Australia is the driest continent on Earth, yet the first European
settlers and those who followed them succeeded in building a vast
agricultural infrastructure that fed not only Australia’s
growing population but the rest of the world as well.
Our engineers turned the rivers inland, developing national icons
like the Snowy Mountains Scheme that enabled vast irrigation networks
to bring water to places where rainfall was never reliable enough.
Yet drought still threatens our farmers on a regular basis, and
the past year has seen the worst on record. In Victoria’s
Goulburn Valley, for instance, tomato farmers are finding that
it is more profitable to sell the water in their dams than to
sow the next crop.
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In this issue of Australasian Science, a team of meteorologists
reports that global warming is a factor in the current drought,
as well as those to come (see pp.14-17). While low rainfall is
the hallmark of any drought - and last year the Murray-Darling
Basin received only 45% of normal levels - last year Australia
“recorded its highest-ever average annual daytime maximum
temperatures, following a warming trend that has intensified over
the past two decades.
Temperature is a significant factor in drought. When the weather
is hot, any moisture in the soil evaporates so what little rain
falls during a drought does not make it to the root zone. Indeed
rainfall and temperature charts over the past 50 years clearly
show our country being sunburnt during years of drought.
Unfortunately the long-term trend is looking dismal for our farmers.
Australia’s average temperature has increased by 0.7°C
over the past 50 years, and that trend is expected to continue
due to global warming brought about by greenhouse gas emissions.
The irony here is that Australia is one of the worst greenhouse
polluters in the world, and has even rejected the most favourable
terms offered to any country under the Kyoto Protocol.
Government and industry groups may well baulk at the cost of compliance
with the Kyoto Protocol, but one wonders how much the economists
have factored in the cost of non-compliance.
Guy Nolch
Editor
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