Australia's fire authorities had a nervous Christmas.
Throughout the festive season planets were aligning in a way that threatened devastation.
Not only was a vast ''heat dome'' developing, but it came with hot, dry winds and the promise of lightning storms. All this was brewing above a landscape that had experienced two years of rainy La Nina weather cycles that promoted forest growth, followed by a four-month, record-smashing dry spell.
The nation was packed with fuel.
''I hadn't seen anything like this before, not in this combination,'' said Shane Fitzsimmons, the commissioner of the NSW Rural Fire Service.
Fitzsimmons has spent most of his working life fighting or planning to fight fires since joining Duffys Forest rural brigade at the age of 15. But this week was something new.
''In all our available records, we can't identify conditions like this in NSW,'' he said. ''We have seen blips on the record before that were more extreme in one way or another but what we are experiencing is a sustained set of weather conditions that is made for fires.''
By the new year, Tasmania was starting to burn and uncontrolled fires were breaking out in parts of South Australia, Western Australia and Victoria. Most of NSW was to be spared for a few more days, shielded along the thickly forested coast by a trough of cooler weather.
''We knew it was coming and we had issued clear warnings, because a lot of the time before Christmas was unseasonably dry and there was no meaningful rain around. But it was not until Sunday night that we knew this was going to be a really tough week,'' Fitzsimmons said. ''We got the four-day forecasts and, by that point, [were] thinking very tactically about what to do on the ground.''
In NSW alone there are more than 80,000 people directly involved in the firefighting business - more personnel than the army, navy and air force combined. They are drawn from the Rural Fire Service, the urban fire brigades, known as Fire and Rescue NSW, the national parks service and Forests NSW.
Nine-tenths of them are volunteers.
The network is co-ordinated from the RFS operational headquarters, a building designed as a firefighting nerve centre that can process dozens of warnings and advise commanders simultaneously.
This week the atmosphere was a little like the conning tower of a submarine as reports of more than 120 fires flooded in. Emergency incidents are signified by flashing lights, indicating that more resources need to be piled in.
Before the first embers started swirling across the Princes Highway on the NSW south coast on Tuesday the decision to shut it to traffic and pull firefighters back from the most dangerous part of the blaze had already been made.
''I think we've got to give nothing but accolades to the volunteers on the front line but also the people who don't get noticed - the area managers, the staff at the centre - they are a well-oiled team,'' the commissioner said.
Australia is seen internationally as the world's leading nation when it comes to fighting fires. But there are still serious, unresolved debates about preparing for future fires.
The events of this week will refine that learning process.
''We do a pretty good job in Australia with most bushfires and floods,'' said Professor John Handmer, the director of the Centre for Risk and Community Safety at RMIT University, in Melbourne. ''But when we start getting events that are rarer … we definitely don't do that well compared to what we'd like to do.''
An ageing and increasingly overweight population, combined with a growing population sprawling into city fringes surrounded by bush, would increase exposure and vulnerability to fire, Handmer said.
The Black Saturday fires in Victoria revealed people aged 70 or over were twice as likely to die in a bushfire.
''A lot of elderly people had experienced fires before and thought that they would be able to deal with it,'' Handmer said. ''[An ageing population] means that there's more people who have various forms of disabilities and who are on medication.''
Historically, flooding had killed more people than fire but that could be changing, Handmer said.
One of the controversial recommendations from the Black Saturday interrogation was that properties in areas of unacceptably high risk should be bought back by government.
''People shouldn't be living in areas of unacceptably high risk by definition,'' Handmer said. ''We need a public discussion about what constitutes 'high risk'. We could save ourselves billions of dollars by avoiding the really high risk areas.''
AS RESIDENTS of fire-ravaged parts of the Tasman Peninsula finally get to return to inspect the damage to property and livestock, another quite different group is gathering in Hobart.
About 270 scientists, including 13 leading Australian experts, will start a week of meetings at the conference centre connected to the city's Wrest Point Hotel Casino. The gathering marks the fourth meeting of lead authors for the Intergovernmental Panel on Climate Change's group examining the physical science of global warming.
The group is to release its part of the fifth assessment report into climate change in September, with the other two groups - examining impacts of climate change and mitigation - scheduled to disclose their final reports in March and April next year.
The IPCC's chairman, Rajendra Pachauri, will open the meeting's plenary session on Tuesday.
While the acting Opposition Leader, Warren Truss, branded the links between the heatwave and human-induced climate change ''utterly simplistic'', Australia's leading scientists don't find the assessment controversial.
''Although Australia has always had heatwaves, hot days and bushfires, climate change has increased the risk of more frequent and longer heatwaves and more extreme hot days, as well as exacerbating bushfire conditions,'' says a report on the heatwave produced by the federal Climate Commission, to be released on Saturday. ''Essentially, climate change is making these natural extreme weather events worse.''
While anecdotal accounts of extreme temperatures stretch back to the earliest records of Australian settlement, the increasing number and frequency of new records this year are an indication that the change has moved beyond random variation in weather.
''Australia's average temperature has already risen by 0.9 degrees Celsius since 1910,'' the commission's report says. ''This is consistent with the global trend of increasing average temperature.
''Globally, the 10 hottest years on record have all occurred in the last 15 years.
''A small shift to higher average temperatures leads to large increases in the number of extreme heat events. For example, the number of record hot days across Australia has doubled since 1960 with an increase of 0.9 degrees Celsius.''
And the records tumbled like never before in the last week. Monday posted an average maximum across the country of 40.33 degrees, eclipsing the previous high of 40.17, set on December 21, 1972. Tuesday came in at 40.11, making it third-highest on record - and meant eight of the 20 hottest days in a century of records have date stamps of 2013.
Leonora, a tiny town in the Goldfields-Esperance region of Western Australia, posted 49 on Wednesday, marking the hottest single peak in the fortnight-long heatwave but temperatures of 50 degrees remain possible this weekend, as towns from Moomba to Birdsville and Bourke cop the latest blast of heat.
Dr John Nairn, the weather bureau's acting regional director for South Australia, is not so concerned about the extreme mercury bursts, nor does he share the media's interest about when and where the long-standing 50.7 record, set in Oodnadatta on January 2, 1960, will finally be broken.
As a global expert in heatwave stress, Nairn is more interested in the other end of the day.
''The minimum is probably much more important than the maximum because, if you can't discharge heat from a hot day, you are going to have a problem facing the next one,'' he said.
Mortality is affected by how much the body is able to cool down overnight and the sustained high minimum and maximum temperatures provide the worst heat impact, he said.
The statistics from the current scorcher include the second-highest average minimum day on record - 24.52 degrees last Tuesday - though the direct effects on human health are hard to calculate.
''The heatwaves are very severe but are they impactful? … The research isn't there,'' Nairn said.
Among the people most at risk from severe and sustained heat are the elderly and the socially isolated, while some people who take drugs for mental illness may need help, he said. ''The drugs reduce their awareness of the heat and also can limit their bodies' ability to respond appropriately.''
Nairn has worked on developing heat stress indices for the World Meteorological Organisation, which may be applied in Australia if funding becomes available.
Work by the organisation last year looked at developing a new heatwave index that calculates sustained heat over a period of three or more days. Parameters include the temperature at which sweating shuts down (38 degrees), the temperature at which productivity slows (28 degrees) and the temperature at which the body suffers damage (50 degrees), according to a draft report.
IN THE 2009 Black Saturday fires, about 25 per cent of the 2000-plus homes destroyed were within one metre of the bush - effectively becoming part of the fuel load - says a royal commission submission by Risk Frontiers, an independent group at Macquarie University.
About 60 per cent of the homes burnt were within 10 metres of the bush. Research into losses from fires over the past century indicate that clearing vegetation to within 100 metres of residences would cut losses from bushfires by about 85 per cent, said Professor John McAneney, the director of Risk Frontiers.
But it is difficult to say if those lessons have been learnt. A survey of residents in four bushland suburbs on the fringes of Sydney, conducted by the University of Technology and the Nature Conservation Council of NSW, found that most people expected a serious bushfire in their lifetime.
''Not only are increased numbers of people making tree changes but we, as a society, are becoming increasingly disconnected from our natural environment,'' said Anne Miehs, the Nature Conservation Council's bushfire project manager.
While the vast majority of those surveyed across Killingworth, Cowan, Westleigh and Waterfall believed reducing risk was a shared responsibility between householders and firefighting authorities, only a small minority had an evacuation plan and fewer than half had thought about it.
More than two-thirds, questioned before community workshops last year designed to educate them on how to reduce their vulnerability to bushfire, had not talked to their local fire brigade about preparation.
''Bushfires are a community threat and householders have a responsibility to prepare their properties, but often they don't,'' said Louise Boronyak, a social researcher at the Institute for Sustainable Futures at UTS.
The evidence this week suggested that community attitudes might be changing. The view among the nation's fire authorities is that people respond to clear, decisive information and that the best weapon for saving lives is a public that is attuned to realistic fire risks.
Widespread mobile phone and internet use over the last decade has greatly improved that situation.
''If you reflect on the circumstances of the 1994 fires around Sydney, the amount of reporters and members of the public standing around in skimpy clothing on the front line was ridiculous,'' Fitzsimmons said. ''Things have changed - now they understand the fire business. You have got the whole community working with the authorities.''
A decision taken at the Lidcombe fire headquarters on Monday night was the state's first big test of the post-Black Saturday warning system. Text messages were approved by fire authorities and sent out to about 780,000 people in the areas of the state facing catastrophic fire risks - the Illawarra, the Shoalhaven and the southern ranges. About 230,000 landline calls were answered.
''We have never had this kind of reach before,'' Fitzsimmons said. ''We can deliberately reach people with clear, simple messages based on the best information - even people who are camping, or on holidays in caravan parks.
''Technology is letting us do this and, to some extent, it is changing the game of fire warnings and, ultimately, public safety … So I don't think it's all down to luck.''