NSW Rural Fire Service crews burn a containment line around a property at Colo Heights, northwest of Sydney, Nov. 16, 2019. AAP Image/Dan Himbrechts/via REUTERS. (Stringer/Reuters)
This year, California and Australia have seen major wildfires simultaneously, both as a result of similar conditions — extremely dry weather, unusually high temperatures and strong winds. But the two fire-prone regions have major disparities in how well they prepare their residents for threatening fire weather conditions and active blazes.
In many ways, Australia is far ahead of the United States when it comes to warning its population about bush fires, and this may be playing a role in keeping the death toll there relatively low — at six, so far — considering more than 2.5 million acres have burned there, and more than 400 structures have been lost.
The repeated rounds of high winds and exceptional heat could make conditions even more explosive by Australia’s approaching summer, which is the core fire season in the nation’s southeast. There is also a very good chance that higher-than-average daytime temperatures will linger through March.
In an era of increasingly fierce and fast-spreading blazes, effective warnings for fire are more important than ever. Australia has a revamped wildfire warning system, and it was showcased this month as fires erupted in New South Wales, Queensland, Victoria and South Australia. Many of these blazes quickly threatened communities.
Like severe thunderstorm and tornado warnings issued by the U.S. National Weather Service, Australia’s warning messages indicate where a fire is moving and which communities are in its path. But they also include detailed instructions for both evacuation and survival.
“Residents are heeding the warnings of our emergency services and they are getting out in advance,” Richard Thornton, chief executive of the Bushfire and Natural Hazards Cooperative Research Center in Melbourne said in an email. These warnings, which he said “are now more nuanced, more targeted, and better-timed,” have been tested so that “they are better understood, and those who receive them understand the actions they need to take.”
Bush fire policy shaped by tragedy
Satellite image showing smoke and thermal anomalies (red dots) from Australian bush fires on Nov. 20, 2019. (NASA)
Australia’s current warning system took shape soon after the devastating February 2009 “Black Saturday” fires that killed 173 people in Victoria, many of them outside of Melbourne. This was a new, more ferocious kind of fire caused by a combination of factors including a warming climate, more severe fire weather conditions (higher temperatures and drier, more explosive fuels), along with sprawling development pushing homes closer to wild lands. It challenged decades of experience with and research about Australian bush fires.
“We thought we understood how to deal with bush fire, but Black Saturday showed there was still so much we did not know,” Thornton said.
Many people had been caught by surprise, waiting for an official warning or other sign of danger, and were either unaware of a fire’s location, or were overwhelmed by its speed, intensity and duration.
Less than 18 months after that disaster, a royal commission finished its investigation of the circumstances surrounding each fatality and issued a 4-volume report, with a list of 67 recommendations.
Chief among the suggested reforms was a new emphasis on warnings: Fire agencies needed to clearly communicate a fire’s location, its predicted arrival time, and what actions those in its path should take.
Another top priority was a revision to Australia’s bush fire safety policy — known as “Prepare, Stay and Defend, or Leave Early” or “Stay or Go” — which was established after the 1983 Ash Wednesday fires that killed 75 in Victoria and South Australia, many of whom attempted to leave as fires bore down.
The policy is based on the principle that a well-prepared and well-defended home can be a safe haven during a wildfire. While this may be true during less severe fires, the commission found that during the worst conditions, the best advice is to leave before a fire threatens.
“We have learned much about why people act in a certain way and make decisions under the extreme stress of a natural hazard,” Thornton said. “Because of this, we now have a more realistic understanding of what it means to defend a house and what it is like fleeing through smoke.”
High fire danger on the rise
Dry, shifting winds and skyrocketing temperatures in and around Melbourne, which hit a record 114.8 degrees, helped fuel the Black Saturday fires. But the area’s warming and drying climate set the stage for the disaster. The lead-up included the warmest decade (1999-2009) in 154 years of record-keeping, a historic 12-year drought, and a record-breaking heat wave at the end of January 2009.
In fact, conditions were so extreme that a new category — “Catastrophic” (or “Code Red” in Victoria) — was added to the country’s Fire Danger Rating scale, a measure of how difficult fires will be to control, based on wind speed, humidity, temperature, and vegetation dryness. There has been a clear increase in extreme fire weather and the length of the fire season, particularly in the southern and eastern part of the country, due in large part to human-caused warming.
Trends from 1978 to 2017 in the annual (July to June) sum of the daily Forest Fire Danger Index — an indicator of the severity of fire weather conditions. Positive trends, shown in the yellow to red colors, show an increase in length and intensity of the fire weather season. (Australian Bureau of Meteorology.) (BOM)
Higher fire danger ratings can also mean escalating losses to life and property.
“Australian fire agencies advise residents to have a bush fire plan and to leave early, well ahead of a fire occurring on high bushfire risk days,” said Amanda Leck, Executive Director of the Australian Institute for Disaster Resilience, in an email. “We further advise that under catastrophic fire conditions, it is not possible for residents to defend their homes and that they should leave the area well before a fire starts.”
A scaled warning system, linked to weather conditions
In September 2009, a national agreement established a new framework for bushfire warnings, one that would be linked to the Fire Danger Rating scale.
Australia’s fire warning protocol kicks in when there is an actual fire on the ground, with three levels of warnings, depending on a fire’s location, how fast it’s moving, and the fire danger rating for that day.
An Advice level is issued for fires that don’t yet pose a threat but require close monitoring; a “Watch and Act” notice means a fire is spreading and residents should either prepare to leave or leave immediately. An Emergency Warning — the highest alert — warns residents to leave immediately.
Also, if the fire front is imminent, a notice will state that it’s “too late to leave,” and provide instructions for survival while sheltering in place.
Given the severe fire weather conditions so far this Austral spring, many such emergency warnings have been issued, more than 10 of them in a single day, in fact.
“It is really about the ‘least bad’ option at this point,” Leck said. “Ideally residents will have taken advice from previous warnings and evacuated prior to the arrival of the fire front.”
Thornton believes the improved warnings saved lives during an outbreak of fast-moving fires between Nov. 8 and Nov. 12.
“The fire conditions were the worst conditions that have been faced in New South Wales, but the focus on risk communication and warnings, along with our improved knowledge of fire behavior, weather, better fire spread mapping technology, and the delivery platforms we now have available like apps and warning distribution via text and phone, combined to make a real difference to the outcome,” he said.
In California, it’s all about local evacuation orders and many agencies
This Nov. 8, 2018, file photo shows a vintage car among debris after the Camp Fire tears through Paradise, Calif. (Noah Berger, File)
Contrast Australia’s approach with that of California, where evacuation orders are issued by local law enforcement, such as a county sheriff’s office, and different counties use different platforms to disseminate wildfire information.
“If you keep it local, you have local people involved who know the areas,” said Scott McClean, CAL FIRE’s public information officer. “With local knowledge, you are able to get to everyone.”
When the Kincade Fire ignited at 9:27 p.m. on October 23, the Sonoma County Sheriff’s Office used wireless alerts and sirens to notify residents as the fire spread, and eventually ordered the entire town of Geyserville to evacuate early the next morning. There were no fatalities.
While California was better prepared this year, the drawback of the evacuation order approach is that it might not be able to keep pace with the most extreme fires.
“The system works if you have enough time,” said Tom Cova, a wildfire evacuation expert and professor of geography at the University of Utah.
The 2017 Tubbs Fire in wine country and the 2018 Camp Fire in Paradise “were about the worst hand an emergency manager can be dealt,” he said.
In this Tuesday, Nov. 19, 2019, file photo, smoke haze covers Sydney as wildfires burn near the city. (Rick Rycroft, File)
Those deadly blazes reached communities in under two hours, and many were not even aware of the danger, or what to do, until it was too late.
A more centralized system, like the one in Australia, could allow the public to access information about the location and spread of a dangerous fire in real time.
Within the Weather Service there is an official fire warning for an out-of-control blaze that poses a threat to a community. But forecasters can only issue these alerts, which could include evacuation orders, at the request of a local emergency manager.
The fire warning is therefore rarely used, and the Sacramento and Oxnard offices were not requested to issue one during the 2018 Camp or Woolsey fires.
In addition, NWS social media accounts as well as state and local agencies don’t all operate based on the same agreed-upon warning level criteria, like they do in Australia. There is no “emergency warning” telling people that it’s too late to try to outrun a fire, and what to do to try to survive.
This may be due in part to the decentralized approach the United States has to weather forecasting and warnings, with a hodgepodge of National Weather Service, state and local agencies, as well as private weather companies all in the mix.
It may also be that many different agencies — Cal Fire, the U.S. Forest Service, local fire departments, county sheriffs’ offices, weather forecasters and emergency managers — are all operating without a cohesive and coordinated framework underpinning their work.
Australians have had more time to prepare for the new normal of extreme fires — their wake-up call came over ten years ago. Ultimately, the success or failure of any warning system, including Australia’s, will be judged by its ability to cope with quickly cascading events.
“How much time did you have? That is the key question,” Cova said.
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