The Newscorp line.
Time for a reality check on the causes of bushfire risk
Oceanic cycles
The best
evidence so
far is that
weather
patterns, not
climate
change,
increase the
danger of
catastrophic
fires.
● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
Robert Hadler
Thenational outpouringof griefandanger
at the consequences of the recent drought
andhorrendousbushfires acrossmuchof
Australia is understandable, but it is not the
best platform to assess corporate risk or
makepolicy decisions.
WhenRussellCroweandothermovie
stars at the GoldenGlobes reinforce the
popular perception thathuman-induced
climatechangeis the cause of the drought
andbushfires, it is time for a reality check.
Companieswith a big regional footprint
suchasCommonwealthBank, Coles,
TelstraandAustralia Postandleading
agribusinessessuchas Elders,BegaCheese
andGrainCorprequire sophisticated riskmanagementstrategies
for weather events.
Tobeeffective, theserisk-management
strategies require forward-looking
indicators that allow companiesto position
their operationsahead of weather events
rather than simply react to them.
Thesameriskmanagementstrategies
shouldbein place forourstateandnational
parks,emergencyservices, thearmed
services,anddecisionmakersat the state
andfederal level.
Fortunately,wehave the data. Scientific
analysisshowsthat the primary drivers of
rainfall,andtherefore droughtandbushfire
risk, in Australia are four separate but
sometimeslinked weather patterns in the
Pacific, IndianandAntarctic oceans.
Theseweather patterns are: the ElNin˜o
Southern Oscillation (ENSO); the longertermInterdecadal
Pacific Oscillation (IPO),
whichaffectsENSOevents; the Indian
OceanDipole (IOD);andthe Southern
AnnularMode(SAM).
In simple terms, sea temperatures in the
Pacific, IndianandAntarctic oceans directly
influenceourannual weather cyclesand
drive surface temperaturesandrainfall
across Australia.
Whenthese weather cycles are positive,
rainfall is lowerandthe risk of droughtand
summerbushfires is higher,andwhenthey
coincide, the risk of a prolongedandsevere
droughtandbushfires ismuchhigher.
Theseweather patterns are regularly
monitoredbytheCSIROandBureauof
Meteorologyandprovide corporate
Australiaandgovernmentdecisionmakers
with effective forward-looking indicators
of droughtandbushfire risk each year.
In the past 12 months,anElNin˜oweather
pattern in the PacificOceanandtheIOD
havebothbeen positive, a dreadful
combination that provided the platform for
the droughtandbushfires.
Tobefair, whileweknewthe risk,westill
did notknowthe exact location, timing
durationandintensity of the droughtsand
bushfires thatwouldoccur.
Somehaveargued that the
unprecedented extentandferocity of the
droughtandcurrent bushfires across
Australia isduetohuman-inducedclimate
change.However,historical analysisshows
Australia has sufferedmanybig droughts
andbushfires.
The1974-75 bushfires in outbackNSW,
Queensland, South Australia,Western
Australiaandthe Northern Territory burnt
117 million hectares,comparedwith 8.4
million hectares burnt so far in 2019-20.
Asthe early 1970s fireswerewellaway
frommetropolitan areas, did not affect
holidaymakers, did not destroymany
housesanddid not kill asmuchlivestock,
they did nothave a big emotional impact.
ResearchbyDanielle Verdon-Kiddand
AnthonyKiemin2009foundthat the three
big droughts in Australian history, the
FederationDroughtbetween 1895and1903,
theWorldWarII droughtbetween1937and
1945andthe BigDryorMillennium
Droughtbetween1997and2009wereall
directly causedby oceanweather cycles.
Theresearchshowsthat the direct causes
of each droughtweredifferent.The
FederationDroughtoccurred during
sustainedENSOactivity in the Pacific
Ocean, theIODis thought tohavebeenthe
maindriver of theWorldWarIIDrought
andtheSAMwasthe chief cause behind the
Big Dry.
ff
Notenoughwasknownabout the effects
ofoceanweather patterns to prepare for the
Federation orWorldWarII droughts, but a
great dealwaswasknownaheadof the Big
Dryandthe recent droughtandbushfires.
Assatellite monitoringandweather
modelling improves, there is simplyno
excuse for business executivesandboard
directors orgovernment decisionmakersto
beunpreparedfor extremeweather events
each year.
Someargue thathuman-inducedclimate
changehas brought forward –or is
increasing the frequencyandintensity of –
ElNin˜oandIODimpacts,andtherefore
droughtandbushfire risk in Australia.
ResearchbySarah HarrisandChris
Lucasin 2019 foundthatoceanweather
cyclesdonot explain the rising average
temperaturesandlower rainfall in
south-east Australia over the past45years,
andthey suggesthuman-inducedclimate
changeis probably driving this.
However,the HarrisandLucasresearch
concludes: ‘‘Thedynamicsof global
warmingandits interactions withmodesof
inter-annualanddecadal variabilityandits
effectsonfire weather in Australiaremain
uncertain.’’
This conclusion does not invalidate the
theory about the effects ofhuman-induced
climatechangeonour weather – it just
meanswedonothaveenoughinformation
yet forsoundriskmanagementor policy
development.
Verdon-KiddandKiemalso concluded:
‘‘Further understanding intohowmultiple
physicalmechanisms,including
anthropogenic climate change, interact to
drive south-east Australia’s climate ... is
required ... Failure to address these issues
will result in droughtmanagement
strategies continuing tobelargely
ineffective in reducing Australia’s
vulnerability to drought.’’
Thesamelogic applies to bushfires or
cyclonesandfloods.
Anyinquiry into or policy response to the
ongoing bushfiresmustaddress this issue.
Weurgently require further scientificwork
to provide greater certainty about the
interactionbetweenoceanweather events
andthe location, timing, durationand
intensity ofhuman-inducedclimate change.
Onlythen willwehavesufficient data to
makesoundlong-term businessandpolicy
decisions.
RobertHadler is aseniorbusinessadviserand
board director.