Lukas Coch/European Pressphoto Agency
Firefighters battled a grass fire in Oura, near Wagga Wagga, Australia, on Tuesday. On Monday, Australia’s hottest day on record, the national average was 104.59 degrees.
SYDNEY, Australia — Australia on Wednesday was grappling with an unprecedented heat wave that has sparked raging bushfires across some of the country’s most populated regions — pushing firefighters to their limits, residents to their wits’ end and leaving meteorologists tracking the soaring temperatures into uncharted territory.
Four months of record-breaking temperatures stretching back to September of last year have combined over the past week with widespread drought conditions and high winds to create what the government had labeled “catastrophic” fire conditions along the heavily populated eastern and southeastern coasts of the country, where much of the population is centered.
Data analyzed on Wednesday by the government-run Bureau of Meteorology indicated that national heat records had again been set — Tuesday was the third hottest day on record at 40 Celsius (104 Fahrenheit) and the mean national temperature average was the highest in history, breaking a record set just the day before, on Monday. Meteorologists have taken the extraordinary step of adding two new colors to its temperature charts to extend their range to 54 degrees Celsius (129 Fahrenheit) from the previous cap of 50 degrees Celsius (122 Fahrenheit) to account for the climbing temperatures.
“If you look at yesterday, at Australia as a whole, it was the hottest day in our records going back to 1911,” said David Jones, manager of climate monitoring prediction at the Bureau of Meteorology. “From this national perspective, one might say this is the largest heat event in the country’s recorded history.”
With the record-breaking heat, firefighters were struggling to contain the huge bushfires in Australia’s most populous state, New South Wales, which have swallowed around 500 square miles of forest and farmland since they erupted on Tuesday. Fires on the island state of Tasmania off the country’s southern coast have destroyed more than 300 square miles since Friday.
No deaths have been reported in connection with the fires, although about 100 people remain unaccounted for since a fire destroyed around 90 homes in the Tasmanian town of Dunalley, east of the state capital of Hobart, last week.
Thousands of head of cattle and sheep are believed to have died already in the fires, which have torn through some of the country’s most productive agricultural and farming regions. Some 10,000 sheep alone are believed to have died in New South Wales, according to the state government’s Department of Primary Industries.
Despite a brief respite from the searing heat in some coastal areas on Wednesday, the government has warned that the hot spell was only just getting started as the so-called “Dome of Heat” began moving up the eastern seaboard away from Sydney, where it was expected to deliver more blistering weather to Brisbane, Australia’s third largest city.
NASA published alarming photographs of the enormous fires, which have grown so large that they are visible from outer space, allowing them to be photographed from the International Space Station on Tuesday. The intensity of the bushfires and the unrelenting nature of the heat have already led some climate scientists to criticize what they see as an indifference to the realities of man-made climate change, which is widely believed to be the driving factor behind these events.
“Those of us who spend our days trawling — and contributing to — the scientific literature on climate change are becoming increasingly gloomy about the future of human civilization,” Elizabeth Hanna, a researcher at the Australian National University in Canberra, told The Sydney Morning Herald. “We are well past the time of niceties, of avoiding the dire nature of what is unfolding, and politely trying not to scare the public.”
Dr. Jones, the government climate scientist, echoed that opinion.
“This event is turning out to be hotter, more spatially expansive and the duration is quite remarkable,” he said in an interview. “And that suggests climate change.”
At least 141 fires continued to rage in New South Wales on Wednesday, with 31 of those fires burning out of control. The deputy commissioner of the state’s Rural Fire Service, Rob Rogers, told reporters that it was a bad sign that the fires could not be contained during the brief drop in temperatures.
“We’ve got a huge swath of New South Wales that potentially is going to get new fires again this afternoon,” Mr. Rogers said. “It will be an absolute battle to get containment on most of those fires before the return of the hot weather on the weekend.”
Tuesday’s new high adds to a growing list of records the Bureau of Meteorology has recorded during this extended heat wave: the first time the country has recorded seven consecutive days of temperatures above 39 degrees Celsius (102 degrees Fahrenheit); the year with the most record hot days in Australia since national records began in 1910, and nationwide average temperatures on each of the first eight days of 2013 that were among the top 20 hottest days on record here.
Dr. Jones warned that there was no sign that temperatures would stay down even as the heat wave appeared to slightly recede in Sydney on Wednesday.
“We expect it to stay very hot across inland Australia for the next week,” he said. “Beyond that it’s hard to say.”
