2 November 2007
The findings of Australia’s
most extensive study to date of the behaviour of high-intensity
bushfires in eucalypt forests – Project Vesta –
provides valuable new tools and information for fire managers
across Australia.
The Bushfire CRC backed the multi-million dollar study conducted by
the Department of Environment and Conservation, Western Australia
and Ensis – CSIRO’s forestry joint venture with New
Zealand’s Scion. It was released in Perth by the Western
Australian Environment and Climate Change Minister, David
Templeman
Bushfire CRC Program Leader and Ensis Bushfire Research Leader
Jim Gould says the 10 year study provided data to develop a better
system for predicting the spread and intensity of wildfires.
“Existing systems for predicting forest fire behaviour work
well for low-intensity fires such as prescribed burns, but can
under-predict the spread of high-intensity summer fires by a factor
of three or more,” he says.
“As a result of this research we have developed a new
bushfire spread model for summer wildfires that will provide the
basis for a national fire behaviour prediction system for dry
eucalypt forests. The study also provides new information of
critical importance to firefighter safety by highlighting the
sudden jump in speed and intensity of a fire that takes place when
a wind change turns a flank-fire into a head-fire,” Mr Gould
says.
Former project leader, CSIRO Honorary Fellow Phil Cheney, says the
research resulted in a number of important breakthroughs that will
improve the ability of fire agencies to manage fire risk.
“This study has enabled us to get a measure of factors that
have not previously been quantified, such as establishing the parts
of the fuel structure that influence the rate of spread,” he
says.
“As a result, we now have a vastly improved
understanding of the fundamental relationships between fire
behaviour and all fuel types of similar structure. This enabled us
to develop a new field guide for fire managers that relates fire
spread to fuel structure and weather conditions across the entire
country whereas, previously, fire behaviour guides were specific
only to certain vegetation types,” Mr Cheney says.
Bushfire CRC and Department of Environment and Conservation
bushfire scientist Dr Lachie McCaw says one of the key findings
from Project Vesta is that hazard reduction by prescribed burning
will reduce the rate of spread, flame height and intensity of a
fire.
“Prescribed burning will also reduce the number and distance
of spot fires by changing the structure of the fuel bed and
reducing the fuel load,” he says. “These effects may
persist for up to 20 years in forests containing rough-barked trees
and shrubby under-storey.
For copies of the Project Vesta go to CSIRO Publishing: www.publish.csiro.au/pid/5993.htm