They also help illustrate how technology has advanced to improve fire readiness and suppression, but also how some approaches have remained fundamentally the same, even as climate change is making a repeat of 1939's fire storms more likely. The Black Friday death toll was shocking enough (at least 71) to prompt a royal commission in Victoria led by Judge Leonard Stretton. The commission's report ran to 35 pages and was completed in less than four months – rather more concise and speedy that its recent counterparts. 'Shadow of dread' Today the report appeals as much for its lyricism as the sober judgements that would lead to the creation of Victoria's Country Fire Authority by 1945, when the war's end turned attention back to local priorities. "The soft carpet of the forest floor was gone; the bone-dry litter crackled underfoot; dry heat and hot dry winds worked upon a land already dry, to suck from it the last, least drop of moisture," the report's introduction reads.

“Men who had lived their lives in the bush went their ways in the shadow of dread expectancy," it said before detailing the impacts of the "devastating confluence of flame” that had been "lit by the hand of man". The results included whole townships "obliterated in a few minutes", while the monstrous winds accompanying the flames uprooted huge trees that were consumed by fire. "[F]ormer forest monarchs were laid in confusion ... piled one upon another as if strewn by a giant hand,” Stretton wrote. Norm Goldings used his trusty DeSoto to rescue nearly 100 people near Noojee in Gippsland during the 1939 Black Friday bushfires. "In my view, Black Friday remains Australia's largest fire in terms of its size – especially in Victoria, ACT and South Australia – and its impact on the population, proportionally," says Tom Griffiths, emeritus professor of history at the Australian National University. "Most of the deaths were people living and working in the bush at remote sawmills, for the interwar years were a period of intensive milling of mountain ash in the rugged Victorian ranges," he says. "Stretton recommended that sawmills be moved out of the bush and into the towns."

But moving the mills out of the forests only took them so far from harm's way. Narbethong was one such town destroyed in 1939. Fast forward to Victoria's Black Saturday fires in 2009 (which has its 10th anniversary next month) and the town was again among those hardest hit, with its sawmill torched. Killer heatwaves Just as in the 2009 fires – perhaps the closest analogue to 1939 – the death toll in the accompanying heatwave easily exceeded that of those who burned to death. Lucinda Coates, a senior risk scientist at Risk Frontiers and a researcher at the Bushfire and Natural Hazards Co-operative Research Centre, estimates at least 420 people died in the 1939 event across Australia. More than three in four of those were in NSW "The series of heatwaves were accompanied by strong northerly winds, and followed a very dry six months," Coates says.

“The January 1939 event was notable for its longevity and record daily temperature maxima." While Melbourne hit 45.6 degrees and Adelaide 46.1, Bourke in north-western NSW sweltered through 37 consecutive days above 38 degrees. Menindee, site of this week's huge fish kill due to stagnant Darling River flows and extreme heat, reached 49.7 degrees on January 10, 1939 – a statewide record that stands to this day. “Home refrigerators were rare and air-conditioned buildings were unknown," Coates says. "Relief was sought at the beaches and baths; there were by then no inhibitions about mixed bathing.” Workers leaving the Noojee area in Gippsland after the 1939 Black Friday bushfires. Record-setting heat and drought

Linden Ashcroft, a researcher of climate history at the Bureau of Meteorology, says the weather in early 1939 was notably severe. Four of the five hottest days on record for New South Wales as a whole were in January 1939, and two of the five hottest days in Victoria, she says. Victoria's hottest day is now February 7, 2009, just before the Black Saturday blazes. Melbourne hit a record high of 46.4 degrees in the late afternoon. "The second week in January [1939] is generally regarded as the most extreme heatwave to affect south-eastern Australia during the 20th century," Ashcroft says. Dry conditions played an important role, too, with the fires coming at the end of two dry years that would later be known as the World War II drought, one of the worst on record for south-eastern Australia. "January 1937 to December 1938 were much drier than average across almost all of Victoria and NSW, and remain the driest two-year period on record for much of Victoria's eastern ranges where the Black Friday bushfires caused so much destruction," Ashcroft says.

"December 1938, in particular, was very dry across almost all of eastern Australia, which would have helped to really crisp up any fuel. "Things were so dry that the topsoil blew up into dust storms easily, and did so for much of the summer until much-needed rain fell in February 1939." Scorched trees line the Black Spur between Healesville and Marysville after Black Friday in January 1939. Credit:Department of Primary Industries Lighting up With a hot air mass forming over the continent, the missing ingredient was a strong cold front from a low-pressure system off the south-west coast of Victoria.

With forest workers, graziers and even campers busy lighting fires as normal – the latter "burning to facilitate passage through the bush”, according to Stretton – the flames were ready to be fanned into an inferno. Even without sophisticated weather modelling or satellite imagery to guide forecasters and the public alike, the "shadow of dread" Stretton reported was real, ANU's Griffiths says. "The whole week leading into Black Friday was terrifying in the bush," he says. "No one living in the bush at that time thought their homes were safe – they fled to rivers, creeks, dugouts, mining tunnels and public buildings where they existed." Stretton notes the calamity that befell those who were unable to flee, in particular one mill where all but one of the workers died “while trying to bury [themselves] in the imagined safety of the sawdust heap”. Making progress

Some long-standing good would come out of the inquiry, as Joelle Gergis, climate scientist, notes in her book, Sunburnt Country. Apart from the CFA's creation, recommendations acted upon included "construction of a network of access trails, towers for early detection of fires, the implementation of controlled burns during spring and autumn to reduce fuel loads, and improved fire prevention education", she writes. Those gains were important, not just for humans, given the impact fires had the environment. Mountain ash in the Yarra Ranges, a region burnt out in 1939 leaving a forest largely of a similar vintage. (Image taken 12 January 2019.) Credit:Peter Hannam "Large tree hollows and other important habitats for mammals and birds, such as the Leadbeater's possum and powerful owl, were destroyed when the mature mountain ash forests burned," Gergis writes, noting that reports state the ash from the burning forests fell as far away as New Zealand.

"Local soils took decades to recover from the damage, and in some areas, water supplies were contaminated for years afterwards due to ash and debris washing into catchment areas." Travellers up the Maroondah Highway beyond Healesville on Melbourne's north-eastern edge can see some of the evidence of the 1939 fires to this day. The battalion-like formations of towering mountain ash trees of similar shining white girth bear witness to their common vintage, all circa 1939. Mountain ash logs piled up at a site in the Yarra Ranges, north-east of Melbourne. Ring-counters would get close to 80 on most of them. Credit:Peter Hannam Scientific leaps Richard Thornton, chief executive of the Bushfire and Natural Hazards CRC, said Stretton's report "was the first real attempt to gain a deep understanding of the causes and consequences of a major bushfire".

"This approach continues today as we study fires to learn how to better keep people and property safe in future fires,” he says. Scientific advances means technology available now and in 1939 are almost incomparable. "Not just in firefighting equipment like more protective clothing and vehicles, but in analysing the weather and the land with satellites and aircraft, before, during and after bushfires," Thornton says. "Today we have a much better understanding of extreme bushfire behaviour, and how large bushfires interact with the atmosphere and create their own weather," he says. "There is software to predict the path of a bushfire, and more experts trained to provide more accurate warnings to threatened communities." Human factors

Researchers also provide expert advice on building standards to ensure that new buildings are safer and more likely to survive a bushfire, provided human psychology is taken into account. "That’s one thing that hasn’t changed since 1939," Thornton says, noting that people will continue to want to build on ridges and at the end of one-way roads deep in the bush even with the attendant risks. Griffiths agrees, adding that in terms of research gaps about fire, "they are overwhelmingly cultural". "We know a lot about the physical behaviour of fire, less about the ecological effects of fire, and least of all about the cultural, human dimensions of fire," he says, citing international fire historian, Stephen Pyne: "The cultural paradigm is both the most obvious and the least developed [in fire research]". 'Beyond our imagination'

Thornton from the bushfire research centre adds that studying events like the 1939 and 2009 conflagrations, or the 1983 Ash Wednesday fires in South Australia and Victoria, also have their limitations because historical precedents are only so helpful. “At the time, the 1939 conditions were beyond the imagination of everyone, even those who had lived their whole lives in the bush," he says. "What does the next bushfire that is beyond our imagination look like? What will its impacts be? "Climate change is causing more severe weather more frequently, but demographic changes are having an equal impact and deserve just as much of our attention," Thornton says. "Since 1939, our population has grown from around 7 million to more than 24 million, with more people living, working and playing in at-risk areas."

Climate signals The Bureau of Meteorology and CSIRO biennial State of the Climate report, released late last year, singled out extreme bushfire conditions as among the clearest changes under way as the country's (and world's) climate warms. The most extreme 10 per cent of fire weather days – based on temperature, rainfall, humidity and wind speed – has increased in recent decades across many regions of Australia, especially in southern and eastern Australia, the report said. One consequence is an associated increase in the length of the fire weather season, a view supported by 2018's late-season fires in March and late winter in NSW and Victoria. The trend is particularly notable in spring. "The 1939 heatwave remains a very significant event, but observations show that extreme heat events, from hot days to heatwaves to a warmer-than-average month, are happening more often," Ashcroft says.

She cites the example of 86 extreme hot days (when the Australia-wide maximum temperature was in the top 1 per cent of temperatures recorded) observed during the five-year period from 2013 to 2017. "This is more than double the number of extreme heat days recorded during the 50-year period from 1911 to 1960," she says. One degree headstart Unlike 1939, when Stretton concluded that much of the evidence put to him was "quite false" and "little of it was wholly truthful", researchers have a wealth of data open to scrutiny and cross-checking (even by deniers of climate change). That means they can compare how sea-breezes eased the 1939 heatwave but were largely missing in the belter that swept across south-eastern Australia ahead of Black Saturday.