18/09/2019

An Ill Wind Fans The Flames

Sydney Morning HeraldPeter Hannam

Mark Graham has had a harrowing week with friends and neighbours battling a bushfire that destroyed his cabin and scorched deep into the nearby rainforests of north-eastern NSW.
"This is a Gondwana refugia - these areas have been permanently wet for tens of millions of years and have never burnt," the ecologist said, pausing to take a phone call while working on a seven kilometre-long firebreak near the World Heritage-listed Mt Hyland reserve. "Big swathes are burning right now."
A fire burning in normally damp rainforest near the World-Heritage listed Mt Hyland nature reserve. Credit: Mark Graham
While fire agencies from Queensland and NSW prepare to boost efforts to protect life and property as fire dangers mount again this weekend, Graham and his team of volunteers have no choice but to take up the task of stopping flames where they can.
"These type of trees have no tolerance," Graham said, reeling off tropical species around him such as ancient yellow carabeens, rosewoods and couchtrees. "If the fire comes in, they die."
A soaring yellow Carabeen tree, perhaps a 1000 years old, reaching into a cloud of bushfire smoke near Mt Hyland. Credit: Mark Graham
About an hour away near Dorrigo , Becky Gibson was preparing to host visitors to the camping ground she and her 89 year-old husband continue to run. A week of howling winds and "a lot of smoke", though, have them anxious about the summer to come.
"Normally it's quite damp but it's very tinder dry right now," Gibson says, noting rain gauges had collected just a quarter of typical yearly rain of about 2000 millimetres. "I've never seen anything like this," she says of her four decades in the area.

'Significant overture'
A wide arc of eastern Australia is primed for a busier than usual fire season. Large areas of NSW and Queensland are in the midst of a record drought and the Bureau of Meteorology forecasts pointing to below-average rainfall and warmer-than-normal temperatures for the rest of 2019 for most of the nation.
Ross Bradstock, Director of the University of Wollongong's Centre for Environmental Risk Management of Bushfires, said fire danger ratings will likely mount ahead of the passage of each cold front. Those bursts of hot, dry and gusty winds can be expected to gradually shift southwards to Sydney and beyond.
"We've got the ultra-dry fuels now, and inexorably you’ll get ignitions," Bradstock says. "We’ve had an overture and a pretty significant one. I think people down here better start getting their act together right now."
A bushfire burns near Tenterfield in northern NSW. Credit: AAP
For Peter Petty, mayor of Tenterfield, the overture has been an extended one. His town in northern NSW has among the tightest water restrictions - at level 4.5 - in the country, and it has had fires burning near its fringes for the past week.
Residents from nearby areas have been evacuated to the showgrounds, which along with other public gardens in this town of 3500, is gradually turning into a dustbowl.
"There's still lots of smoke around," Petty says, adding fire authorities "continue to be outstanding". Tankers had to spray treated sewage water to spare other supplies.
The threat is here "every day", he says. "We're a long way out from being out of the woods."

'Like mid-summer'
Among the lead agencies gearing up for long fire season is the NSW Rural Fire Service, a body that boasts an annual budget of $385.8 million and counts 72,491 volunteers.
While records show fires this early in the spring have afflicted the Sunshine Coast and other parts of southern Queensland and northern NSW before, the scale has set early challenges. In NSW, for instance, fires scorched some 130,000 hectares, and the three biggest blazes had a fire perimeter of 580 kilometres at the peak.
"There's no record of fire dangers that high that early in those areas in NSW," Rob Rogers, the RFS's deputy commissioner, says. "The fires were burning like it was mid-summer."
Across the state, the "only bright spot" is around Tumut in the Snowy Mountains but mostly because conditions are not as aberrantly dry as elsewhere.
According to the Bureau of Meteorology, rainfall over much of the fire-hit regions has been the lowest on record for the 20 months starting January 2018, and the 32 months starting January 2017. Similarly, the northern Murray-Darling Basin is tracking record low rainfall totals for those two periods.
Rainfall deficiencies over the past 17 months
April 1, 2018 - August 31, 2019 

Source: Bureau of Meteorology
During a recent visit to the Pilliga state forest in northern NSW, her team saw highly stressed trees that had shed their entire canopy and had started to resprout as if they had been burnt. Even some of the regrowth was starting to die.Few people are watching how vegetation is drying out more closely than Rachael Nolan, a researcher for the Hawkesbury Institute for the Environment.
"When that happens, things are pretty bad," Nolan said. "Some were quite serious."
Scribbly gum trees in the Pilliga Forest in north-western NSW look like they are re-sprouting after a fire - but there hasn't been one in that area. Credit: Rachael Nolan
Her main work, though, has been to develop fuel moisture maps using satellites that provide up-to-date data for scientists and fire authorities.
Moisture levels in dead trees and other vegetation can change overnight following a shower but changes in living plants "provide a very good indication of what will happen next week and the week after that".
For the region around Sydney, the indicators point to a rapid drying off, particularly in the Blue Mountains and to the city's north-west.
Mean live fuel moisture content in Sydney region
August 21 - September 5

Source: R.H.Nolan, M.M. Boer and R.A. Bradstock
Nolan stresses having dry fuel "is no guarantee that we will get fires", noting conditions were similarly dry this time a year ago but handy spring rains eased the threat.That said, the rate the vegetation has been curing is greater this year than in 2013, the last year when large fires burnt near Sydney particularly in the Blue Mountains.
Median live fuel moisture content, Sydney Basin
Source: R.H.Nolan, M.M. Boer and R.A. Bradstock
Upward trend in fire risks
Along with the abnormally dry conditions, temperatures in the fire-hit regions were unusual. Maximum readings on September 5 and 6 were about 10 degrees warmer than average, the Bureau says.
What is becoming more typical, though, is the rate at which heat records continue to tumble. Nationwide, for instance, daytime temperatures are tracking the warmest record for the first eight months of 2019 and last summer was Australia's hottest.
Since temperatures are a key component of dangerous fire weather - along with fuel, wind and humidity - it is not surprising climate change is nudging Australia's fire risks higher.
The latest BoM-CSIRO State of the Climate report shows southern and eastern regions have had some of the biggest increases in the fire danger indices in recent decades.
How fire danger risks are rising in Australia
Source: Bureau of Meteorology, CSIRO
Hamish Clarke, a fire researcher at the University of Wollongong and Western Sydney University, said that inter-year variability shows annual fluctuations in fire risks can be "quite considerable" but the trend is clearly upwards.
“Across the country, at a number of high-quality long-term weather stations, there had either been an increase, or no change," Clarke says. "We didn’t find a significant decrease anywhere.”
Climate modelling by Clarke on NSW and ACT and other researchers show the trajectory for temperatures is also upward while the impacts on other fire weather variables such as vegetation or wind speeds are less clear.
“Generally speaking the increases [of fire threats] are much more than the decreases and the areas much more, but some models show some decrease.
“It’s not much comfort because there are more models that are projecting quite large changes in both average and extreme conditions, with spring particularly highlighted,” he said.
Fires erupted in dozens of locations at the end of last week, including near Lithgow in the Blue Mountains. Credit: Nine News
Andrew Dowdy, a senior bureau climate researcher at the bureau, concurs.
"The projections show a clear trend towards more dangerous near-surface fire weather conditions for Australia" based on the McArthur Forest Fire Danger Index, Dowdy states in a recently published report in a Nature journal.

What can be done?
Bradstock says the question of whether human-induced climate change is worsening the fire threat in Australia is "old hat".
“The research has all been done. We don’t need to keep doing it," he says. "The big research challenge is how we’re going to adapt, and build resilient communities, and how will our ecosystems cope with the double combination of fire and drought.”
The Boeing 737, dubbed 'Gaia', in action for the NSW Rural Fire Service. Credit: NSW RFS, via Facebook
Adaptation is taking many forms, including additional "toys" such as NSW's newly bought 737 Large Air Tanker, with its 15,142-litre payload to drop on blazes.
Retardant-carrying drones may also feature but only when costs fall much further, Rogers says.
Instead, residents are more likely to tap into information technology advances that will help them understand the evolving threats near them.
It is only a matter of time before people in bushfire-prone areas will be able to be alerted to changes in fire weather, fuel loads and potential fire behavior.
Already being rolled out in different states is the University of Tasmania-developed AirRater app for smart phones that can provide real-time air quality readings including smoke.
A fire in a dried-out peat swamp near Port Macquarie, for instance has been choking residents for weeks. The new app, complete with sensors, was rolled out within weeks.

Insurance prod
Concern about smoke from hazard-reduction fires is one reason fire authorities sometimes have to curb their burning near large population centres such as Sydney or Melbourne.
A bushfire near Springwood in the Blue Mountains in October 2013. Credit: Dallas Kilponen
Insurance companies, though, monitor closely the work being done, and receive at least annual snapshots of how close vegetation is to properties in fire-prone areas.
Damage claims from bushfires are not yet "loss leaders" for the industry compared with cyclones, floods and storms, Karl Sullivan, head of risk operations for the Insurance Council of Australia, says.
Still, the Council has already declared the early season fires catastrophes, with $13.5 million in loss claims from 120 properties, with the toll expected to mount.
Since the 2009 bushfires, authorities have imposed tighter building codes requiring more fire-resistant materials and design that can cut premiums by about 10 per cent.
“These properties are by no means fire-proof...but they’re definitely more fire resilient, and that’s typically reflected in fire premiums," Sullivan says.
Mark Leplastrier, executive manager for natural perils at IAG, says bushfires were increasingly occurring outside the traditional fire season and in some areas of Victoria, for instance, were a greater risk for insurers than floods.
Fire damage risks were likely to continue to rise - but so were other climate-change perils that were poorly integrated into risk assessments, he says. For instance, houses might be better designed for wind stress in cyclone regions but they may still be hammered by water ingress caused by the higher storm surges.

Avoiding 'ecosystem collapse'
Justin Leonard, research leader for CSIRO's bushfire adaptation unit, said national building codes revised after Victoria's 2009 Black Saturday bushfires still had "significant flaws".
The focus of the new AS3959 code paid too little attention to ensuring builders avoid combustible materials in the roof, walls and below the floor, he said. A better alternative was the NASH steel-frame standard.
For instance, the revised code allowed flammable wooden decks. Residents might also do the right thing and place distance between their house and other structures on their property but still be just 1.8 metres of a neighbour's home.
"There's no special building consideration for that impact," he says.
For Bradstock, the evidence from western US is that Australian cities may be setting themselves up for big fire losses in the future.
"We’re building these very large houses...with very little spaces between houses," he says.
"If you get a fast-moving grass fire, and if it gets into them, there’s the possibility of very extensive spread," he says. "The evidence suggests you’re setting yourselves up for a problem.”
Bradstock said there had been “really no concerted effort to understand the resilience of our human systems to the multiple challenges of drought and fire", and those knowledge gaps could prove costly to communities.
Queensland bushfires: the surprise was how close they came to populated parts of the state. Credit: Cameron Neville, via QFES
Likewise the burning of previously wet wilderness areas of Tasmania and now along the eastern coast in the past week were a reminder that the natural environment may also be reaching thresholds."We just assume that these things are resilient,"he says. "They may not be.”
Up at Billy's Creek near Mt Hyland, Mark Graham was preparing to take a break after a week of battling fires that have charred as much as 100,000 hectares.
"We're trying to save the most ancient of the ancients," he says, adding society still has time to confront the threat of a warming climate before it is too late.
"There's still a chance to avoid having these ecosystems collapse around us."

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