AIRCurrents
Fire Down Under: The Black
Saturday Fires
Editor’s note: On Saturday, February 7, major bushfires broke out across the
southeastern Australian state of Victoria. Known as the Black Saturday fires,
the disaster was the deadliest fire in Australia’s history and one of the country’s
04.2009
most costly natural disasters of any kind. Weeks later, while pockets were still
smoldering, AIR undertook a post-disaster survey of some of the hardest-hit
areas north of Melbourne. In this article Dr. Praveen Sandri, Managing Director
of AIR’s Hyderabad office, reports on the February fires and the findings of AIR’s
survey1 . AIR Senior Research Scientist Dr. Tomas Girnius adds some background
on the history of bushfires in Australia and on the nature of the peril today.
By Dr. Praveen Sandri and Dr. Tomas Girnius
At the end of January and continuing into February of
2009, southeastern Australia was hit by an unprecedented
heat wave. Already suffering from a decade-long drought,
the region additionally had received no rainfall at all for
more than a month. Conditions were so volatile that on
Wednesday, February 5th, Victoria state fire and police
officials held a joint media conference to warn the public of
the danger of bushfires breaking out. On Saturday, February
7th, temperatures in Melbourne, the capital of Victoria, rose
above 46oC (115oF). It was the highest temperature ever
recorded in the city since record-keeping officially began in
1859.
The Victoria Bushfires of 2009
That morning a fire was reported about 65 km (40 mi) north
of Melbourne. It was the first of six major fires that began
that day alone. Propelled by wind speeds gusting to more
than 95 km/h (59 mph), the fires raced across the parched
region. Within a few days 210 people had been killed, 500
injured, and nearly 8,000 left homeless. More than 2,000
homes were destroyed—among some 3,500 structures
destroyed in all. More than 4,400 km2 (1,700 sq miles) of
land was burned. Current estimates suggest insured losses
of between AUD 1.0 billion and 1.5 billion.
That night the two fires merged, creating a front that
stretched for 80 km (50 mi) and became known as the
Kinglake Complex Fire. More than 500 firefighters were
engaged along the arc of the front, assisted by 33 tankers,
a helicopter, and two fixed-wing aircraft. This was the
most deadly and largest of the 23 fires fought that night
and of the 40-some fires fought over the next days. The
destruction wrought by the other fires on Black Saturday
notwithstanding, ninety percent of the fatalities were caused
by the Kinglake Complex Fire.
The “Black Saturday” fires were the deadliest natural
disaster to strike Australia in over a century. The first of the
fires reported that day was called in from the small town of
Kilmore East. The fire quickly erupted into a massive blaze
and spread to the south and east in the direction of the
nearby towns of Wandong, Kinglake West, Kinglake Central,
and Kinglake. Another fire, the Murrindindi Mill Fire (which
is still being investigated for having a suspicious origin) was
reported three hours later near a closed sawmill about 50
km (31 mi) east of Kilmore. It then spread south and east,
toward the town of Marysville about 16 km (10 mi) away.
AIRCurrents
04.09|Fire Down Under: The Black Saturday Fires
By Dr. Praveen Sandri and Dr. Tomas Girnius
According to survivors, the fire sounded like a freight train
as it roared into Kinglake. Its flames reached heights of 18
to 20 meters (60 to 70 feet). Tree tops burst into flame,
home fuel tanks exploded, and quickly fire was everywhere.
Situated at the heart of the Kinglake Complex Fire on
the night of February 9th was the town of Marysville.
Many residents fled to the town’s cricket field, which was
one of several “designated refuge centers.” Eventually,
they numbered about 200, nearly half the town. A Fire
Brigade Strike Team, its retreat from Marysville cut off by
the surrounding inferno, also came to the field. Through
the night, trees just beyond the field’s perimeter exploded
into balls of fire. When flames reached the fire trucks that
had encircled the townspeople wagon-train fashion, the
firefighters turned on their hoses. They had one water
tanker, which held only 650 gallons.
The survey area (shaded regions in Figure 1) is generally
hilly and the roads often wind through forest, following
the contours of the terrain. The trees are mostly eucalyptus
and pine, species with high resin content. And they
are tall—generally reaching at least twice the height of
most buildings—with branchless trunks leading to full,
leafy crowns. Between the trees grow grasses and other
underbrush, though at the time of the survey, all that
remained was a gray ash.
The purpose of the survey was to gather information
on terrain, vegetation, building types and practices, and
damage patterns in a typical bushfire-prone area. The
photos below illustrate some of the salient findings of the
survey.
Miraculously, all those on the cricket field survived.
However, hardly a building was left standing. Marysville was
decimated: at least 45 people were killed, almost one-tenth
the town’s entire population.
AIR Damage Survey
One month after the first of the fires ignited—even as some
fires, although contained, still burned—AIR surveyed areas
in and around the town of Kinglake, about 50 km (30 mi)
northeast of Melbourne. (Marysville and its immediate
surroundings were being treated as a crime scene and
access to it was closed.) The region surveyed was generally
rural and sparsely populated, yet within a 16 km radius (10
mi) of Kinglake at least 130 people were killed in the Black
Saturday fires.
Figure 2. Main Mountain Road, 30 km Northwest of Kinglake. Source: AIR
Roads and other open spaces can act as firebreaks, but
they were not effective in stopping the high speed Kinglake
Complex Fire, as seen here in Figure 2 along the Main
Mountain Road looking north toward Clonbinane. Propelled
by winds of 100 km/h (60 mph), firebrands, embers and 10meter (30 feet) high flames vaulted many barriers.
Figure 3. Commercial Damage. Source: AIR
Figure 1. Areas Surveyed by AIR. Source: Google Maps and AIR
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AIRCurrents
04.09|Fire Down Under: The Black Saturday Fires
By Dr. Praveen Sandri and Dr. Tomas Girnius
Commercial structures, like this store with its masonry walls
and corrugated sheet metal roof, were destroyed as readily
as private homes. Roofs of both residential and commercial
construction were either of sheet metal, as here, or clay
tiles.
Buildings constructed with brick walls, as on the left
in Figure 6, effectively suffered the same as buildings
constructed of wood and/or masonry veneer, although the
walls in most cases remained standing. For wood frame
construction, chimneys are typically the only element still
standing.
Some residents stayed to defend their homes—a risky
decision. The house shown in Figure 4—unusual in having
two stories—suffered only minor roof damage to the lower
extension. The owners said that embers did enter the house
and started a fire in one room, but was quickly doused.
Had the residents not stayed, the entire building would
likely have been destroyed. Other residents who made the
decision to stay and battle the flames were not so lucky.
Figure 6. Masonry Often Remained Standing, with the Rest of the Structure Destroyed.
Source: AIR
Not uncommon was the situation documented in Figure
7: the house on the left is virtually undamaged, while
its neighbor a few meters away (note the time stamp) is
completely destroyed. This damage pattern, captured by
the AIR Wildfire Model for the U.S., has been repeatedly
observed in each of AIR’s damage surveys and can often be
the result of a single airborne ember.
Figure 4. One Home that Survived. Source: AIR
As has been observed in virtually all of AIR’s fire damage
surveys, damage was almost always all or nothing (Figure
5). Very few structures showed only partial damage.
Figure 7. The Arbitrariness of Fire: One Lucky Homeowner Next to One Less Lucky.
Source: AIR
Bushfire Risk in Australia
Figure 5. Complete Destruction. Source: AIR
The Black Saturday fires were only the most recent in a
long history of similarly devastating fires. There have been
Black Sunday, Red Tuesday, Black Thursday, Black Friday
and Ash Wednesday fires. Until this February’s fires, the
Ash Wednesday fires of 1983 had been the most deadly.
Igniting, not without irony, on Ash Wednesday of that
year’s Christian calendar, the fires killed 75 people. Winds
gusted to over 112 km/h (70 mph) producing tornadolike fire whirls, fireballs three meters (10 ft) across, and
temperatures—estimated afterwards from melted metals—
of 2000oC.
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AIRCurrents
04.09|Fire Down Under: The Black Saturday Fires
By Dr. Praveen Sandri and Dr. Tomas Girnius
The largest bushfire remains the Black Thursday fires,
which began on February 6th of 1851. In a matter of
days they burned through nearly a quarter of Victoria
state. At roughly 52,000 km2 (20,000 square miles), the
burnt area was about ten times larger than that of either
Ash Wednesday or Black Saturday. In an era of sparse
population, however, just 12 people were killed—but
thousands of cattle and an estimated one million sheep
perished.
Bushfires are part of the ecology that characterizes the
continent. Most of Australia’s interior is desert or semiarid land that is also relatively flat. Given the continent’s
geographic proximity to the equator, its climate is generally
warm. Temperatures commonly rise to over 38oC (100oF)
and the air holds very little water. Vegetation quickly dries
out—and burns easily.
Eucalypts, which today make up roughly 70% of the
Australian forest and include the widely-known eucalyptus
tree, evolved through millions of years of such conditions.
Rich in highly flammable resins, having branches and bark
that readily strip or shed and quickly accumulate, eucalypts
are fuel waiting for a spark. They also, however, have
evolved features that enable them to tolerate and even
thrive with fire.
These environmental conditions are additionally affected
and shaped by the La Niña-El Niño cycle that spans the
Pacific Ocean. La Niña generally brings wet weather to
Australia. During El Niño years, the opposite happens: highpressure air masses develop over the Australian north and
create persistent warm and dry conditions. They also set the
conditions that drive the winds out of the hot, dry interior
to blow across the southeast.
These climatic systems leave Australia—already the
world’s driest inhabited continent—with a highly variable
rainfall climate. The Australian government’s Bureau of
Meteorology describes the country’s rainfall experience as
having about three good years and three bad years out
of ten. Usually the “bad” period is broken by the return
of La Niña, but this has not happened in recent years and
the continent has had unusually low rainfall for the last
decade. One recent study attributes this phenomenon
to unprecedented warming in the Indian Ocean, which
dictates the strength of the moisture-bearing winds that
travel to Australia—and in recent years those winds have
been weak. Consistent with this interpretation, perhaps, is
an official “Drought Statement” issued by the Bureau of
Meteorology on April 6th, which stated that the record heat
and widespread drought southern and eastern Australia
currently are experiencing “is without historical precedent
and is, at least partly, a result of climate change.”
These factors—together with increased population,
increased construction in the “Wildland-Urban Interface,”
and increasing water-intensive agriculture (that concentrates
diminishing water supplies to certain areas, leaving others
drier)—combine to increase the risk of fires. On average
every year Victoria state experiences about 600 bushfires.
Only about 25% are caused by natural events, chiefly
lightning. An almost equal number are deliberately set:
arson. The rest are attributable to one or another kind of
human-associated activity or accident: campfires, sparks
or exhausts from machinery, fallen utility lines, etc. As
one academic has described it, Australian bushfires are
caused by “lightning, the clumsies and the crazies.” When
conditions come together as they did on February 7th—
long drought, no rain, very high temperatures, and strong
and steady winds—catastrophe is bound to strike.
Editor’s Note: AIR is currently developing a bushfire model
for Australia.
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AIRCurrents
04.09|Fire Down Under: The Black Saturday Fires
By Dr. Praveen Sandri and Dr. Tomas Girnius
1 AIR wishes to extend a warm thanks to Mr. Walter Reinhardt of the Great Barrier Reef Foundation for his
acting as AIR’s guide during the survey.
About AIR Worldwide Corporation
AIR Worldwide Corporation (AIR) is the scientific leader and most respected provider of
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more than 50 countries. More than 400 insurance, reinsurance, financial, corporate and
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©2009 AIR Worldwide Corporation. All rights reserved. 5