NEWS
campusreview.com.au
Better than the BOM
ANU researchers develop
temperature record that eclipses
Bureau of Meteorology efforts.
By Wade Zaglas
Researchers at the Australian National
University have tracked back to
1838 to chart daily temperatures,
identifying more heatwaves since the
pre‐industrial period and a decrease in
cold snaps.
Dr Joelle Gergis, a lead researcher from
ANU, said the study focused on daily
records from Adelaide.
“We’ve been able to place recently
observed daily temperature extremes in a
longer context by using historical weather
records from the Adelaide region,” she said.
“Our analysis shows that snow was once
a regular feature of the southern Australian
climate. As Australia continues to warm, we
have seen a clear decrease in cold extremes
and an increase in heatwaves.”
This historical study of temperature
is considered unique, as most other
investigations have had to rely on monthly
or annual data.
“This is important, as the impact of global
temperature increases on human health,
agriculture and the environment are most
keenly felt through extreme events like
heatwaves,” Gergis said.
To reconstruct the daily weather patterns
from nearly 200 years ago, researchers
examined “hundreds of historical
newspapers and documents” to calculate
the temperature extremes of the past.
Another aspect of the study is that it now
provides information about the pre‐1910
period, which will help to extend the
Bureau of Meteorology’s official record.
Through their painstaking research work,
the academics have been able to identify
specific weather events that impacted
whole communities.
For instance, on 22 June 1908, a cold
snap delivered widespread snow across the
hills surrounding Adelaide. The Express and
Telegraph reported it at the time:
“Many people made a special journey
from Adelaide by train, carriage or motor to
revel in the unwonted delight of gazing on
such a wide expanse of real snow, and all
who did so felt that their trouble was amply
rewarded by the panorama of loveliness
spread out before their enraptured eyes.”
On the other end of the spectrum,
Adelaide sweltered in a heatwave that
included five days over 40°C, from 26 to
30 December 1897. The heatwave was so
severe that newspapers reported heatrelated
deaths, agricultural destruction,
animals perishing in the zoo, bushfires, and
even “burning hot pavements scorching the
soles of people’s shoes”.
Heatwaves such as this provoked
The South Australian Register to write what
would later be prescient remarks for the
future: “May Heaven preserve us from being
here when the ‘scorchers’ try and add a few
degrees to the total.”
“Historical documentary records provide
an understanding of the societal impacts
extreme events had on people during
pre‐industrial times,” Gergis said.
“South Australia is the nation’s driest state,
and Adelaide is the most heatwave-prone
city in Australia. Heatwaves are the most
lethal weather extreme.”
There have been more than 5300 deaths
in Australia between 1844 and 2010 that
have been directly related to extreme heat,
according to the researchers.
Further, South Australia has the
unenviable title of having the “highest
historical heat-related death rate of any
state or territory from 1907 to 2010”.
The University of Melbourne’s Dr Linden
Ashcroft says historical weather records can
be used to discover what Australia’s climate
was like before official meteorological
records began in the early 1900s.
“And there are tomes of old, decaying
journals that haven’t been recovered
and analysed by climate scientists yet,”
Ashcroft adds.
Both Gergis and Ashcroft were even
able to “dust off even more forgotten old
weather journals recently”. Next, they plan
to transcribe new discoveries to go back
even further in time, with the help of citizen
scientists.
Their daily temperature record will be
the longest continuous one in Australia,
and one of the longest in the Southern
Hemisphere.
Their research has recently been
published in Climate Dynamics.
For more on the study and citizen
science programs, visit the Climate History
Australia site at climatehistory.com.au. ■
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