Australia's blistering heatwaves here to stay

The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
The path of destruction in Dunalley.
The path of destruction in Dunalley.
A house destroyed by a bushfire is seen in ruins in Dunalley.
A house destroyed by a bushfire is seen in ruins in Dunalley.
Burnt houses in the community of Dunalley, Tasmania.
Burnt houses in the community of Dunalley, Tasmania.
This house in Dunalley was completely destroyed.
This house in Dunalley was completely destroyed.
The town on the east coast of Tasmania was ravaged, and there are fears of deaths.
The town on the east coast of Tasmania was ravaged, and there are fears of deaths.
The ruins of the school in the Tasmanian town of Dunalley after fire ripped through the area.
The ruins of the school in the Tasmanian town of Dunalley after fire ripped through the area.
Australian reporter Michael Scanlan took this image of what he called the "ghost town" of Dunalley.
Australian reporter Michael Scanlan took this image of what he called the "ghost town" of Dunalley.
Smoke from a bushfire billows over hills near Forcett, about 25 kilometres east of Hobart.
Smoke from a bushfire billows over hills near Forcett, about 25 kilometres east of Hobart.
Clouds from a nearby bushfire are seen over Mount Wellington, Tasmania.
Clouds from a nearby bushfire are seen over Mount Wellington, Tasmania.
Smoke drifts out over the coast.
Smoke drifts out over the coast.
A scene from Bichero, north-east of Hobart.
A scene from Bichero, north-east of Hobart.
Smoke climbs from a fire burning just kilometres from homes in the town.
Smoke climbs from a fire burning just kilometres from homes in the town.
Police Rescue Helicopter crewman Matthew Drumm looks out at the destruction.
Police Rescue Helicopter crewman Matthew Drumm looks out at the destruction.
The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
Fire burning near Dodges Ferry, a small town in south eastern Tasmania.
Fire burning near Dodges Ferry, a small town in south eastern Tasmania.
A fire at Tasmania's Forcett, 30km from Hobart, sends smoke over Park Beach.
A fire at Tasmania's Forcett, 30km from Hobart, sends smoke over Park Beach.

The heatwave that has scorched Australia since Christmas is a taste of things to come, with this week's records set to tumble again and again in the coming years, climate scientists say.

The hottest average maximum temperature ever recorded across Australia - 40.33 degrees Celsius, set on Monday - might stand for only 24 hours and be eclipsed when all of yesterday's readings come in.

The previous record had stood since December 21, 1972.

A fire burns in Ku-Ring-Gai National Park, north of Sydney.
A fire burns in Ku-Ring-Gai National Park, north of Sydney.
Firefighers battling a bushfire in Aberdare, New South Wales.
Firefighers battling a bushfire in Aberdare, New South Wales.
Frantic efforts to damp down properties as the fire approaches.
Frantic efforts to damp down properties as the fire approaches.
Trying to keep cool at the Big Day Out in Sydney.
Trying to keep cool at the Big Day Out in Sydney.
Swimmers and sun bathers at Victoria Park Pool, in Sydney's Glebe.
Swimmers and sun bathers at Victoria Park Pool, in Sydney's Glebe.
Crowds at Wanda Beach as temperatures begin to fall in Sydney.
Crowds at Wanda Beach as temperatures begin to fall in Sydney.
Sydneysiders cool off in Botany Bay near Yarra Bay.
Sydneysiders cool off in Botany Bay near Yarra Bay.
The changed landscape of Baradine Road at Coonabarabran, which was hit by one of New South Wales' worst bushfires in history.
The changed landscape of Baradine Road at Coonabarabran, which was hit by one of New South Wales' worst bushfires in history.
Robina and Felicity Otrupcek standing in front of Robina's home that was water-bombed and remained unscathed as fire burnt through the New South Wales property.
Robina and Felicity Otrupcek standing in front of Robina's home that was water-bombed and remained unscathed as fire burnt through the New South Wales property.
A children's playground destroyed by the massive bushfire in rural New South Wales.
A children's playground destroyed by the massive bushfire in rural New South Wales.
Fire burns alongside the Newell Highway near Coonabarabran, about 350km northwest of Sydney.
Fire burns alongside the Newell Highway near Coonabarabran, about 350km northwest of Sydney.
A fire danger sign on the Hume Highway between Sydney and Melbourne gives a grim warning to locals.
A fire danger sign on the Hume Highway between Sydney and Melbourne gives a grim warning to locals.
Several buildings at the Siding Spring Observatory were damaged.
Several buildings at the Siding Spring Observatory were damaged.
The Siding Spring Observatory the morning after the fire swept through.
The Siding Spring Observatory the morning after the fire swept through.
The fire moves in on the observatory in Siding Springs, in rural NSW.
The fire moves in on the observatory in Siding Springs, in rural NSW.
An aerial photo of the fire threatening the Siding Springs Observatory.
An aerial photo of the fire threatening the Siding Springs Observatory.
'Mopping-up" spot fires at Sandhills in Bungendore, Australia.
'Mopping-up" spot fires at Sandhills in Bungendore, Australia.
NSW Rural Fire Service crews water-bombing fires at Bungendore.
NSW Rural Fire Service crews water-bombing fires at Bungendore.
Carngham Station, in Victoria, was destroyed in the state's bushfires.
Carngham Station, in Victoria, was destroyed in the state's bushfires.
A fireman working on flames near Ballarat, Victoria.
A fireman working on flames near Ballarat, Victoria.
Fire crossing Princes Highway at Deans Gap fire in Shoalhaven, southern NSW.
Fire crossing Princes Highway at Deans Gap fire in Shoalhaven, southern NSW.
A deserted petrol station, close to a fire south west of Wandandian, NSW.
A deserted petrol station, close to a fire south west of Wandandian, NSW.
NSW Rural Fire Service crews tackle a deliberately lit bushfire near Bidwill in Sydney's west.
NSW Rural Fire Service crews tackle a deliberately lit bushfire near Bidwill in Sydney's west.
A bush fire burning near Cooma, south of Canberra.
A bush fire burning near Cooma, south of Canberra.
Smoke rises from the Yarrabin bushfire burning out of control near Cooma, south of Canberra.
Smoke rises from the Yarrabin bushfire burning out of control near Cooma, south of Canberra.
Water bombing at Oura, near Wagga Wagga. New South Wales faces its worst fire risk with temperatures predicted to hit the mid to high 40s.
Water bombing at Oura, near Wagga Wagga. New South Wales faces its worst fire risk with temperatures predicted to hit the mid to high 40s.
Rural Fire Service Commissioner Shane Fitzsimmons (C) at the State Operation Centre.
Rural Fire Service Commissioner Shane Fitzsimmons (C) at the State Operation Centre.
Exercise groups train at sunrise to beat the heat on Sydney's Bronte Beach as temperatures are expected to reach record highs.
Exercise groups train at sunrise to beat the heat on Sydney's Bronte Beach as temperatures are expected to reach record highs.
Singed clothes hang from a clothesline in a backyard affected by a bushfire at Boomer Bay, about 40 kilometres east of Hobart.
Singed clothes hang from a clothesline in a backyard affected by a bushfire at Boomer Bay, about 40 kilometres east of Hobart.
Kutchani, a female lion, eats a frozen milk iceblock at Sydney's Taronga Zoo.
Kutchani, a female lion, eats a frozen milk iceblock at Sydney's Taronga Zoo.
Police Rescue Helicopter crewman Matthew Drumm looks out at the destruction.
Police Rescue Helicopter crewman Matthew Drumm looks out at the destruction.
The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
The settlement of Dunalley, about 40 kilometres east of Hobart, was one of the worst hit by the Tasmanian bush fires.
Fire burning near Dodges Ferry, a small town in south eastern Tasmania.
Fire burning near Dodges Ferry, a small town in south eastern Tasmania.
A fire at Tasmania's Forcett, 30km from Hobart, sends smoke over Park Beach.
A fire at Tasmania's Forcett, 30km from Hobart, sends smoke over Park Beach.

» Australia’s heatwave sparks bushfires

''The current heatwave - in terms of its duration, its intensity and its extent - is unprecedented in our records,'' said the Bureau of Meteorology's manager of climate monitoring and prediction, David Jones.

''Clearly, the climate system is responding to the background warming trend. Everything that happens in the climate system now is taking place on a planet which is a degree hotter than it used to be.''

As the warming trend increased over coming years and decades, record-breaking heat would become more common, Dr Jones said.

''We know that global climate doesn't respond monotonically - it does go up and down with natural variation. That's why some years are hotter than others because of a range of factors. But we are getting many more hot records than we're getting cold records. That's not an issue that is explained away by natural variation.''

Australia's climate is based on an interplay of many factors, including regional and local weather patterns, El Nino and La Nina climate cycles and the Indian Ocean dipole, all superimposed on the greenhouse gas-driven warming trend.

While temperatures vary on a local and regional scale, globally it has been 27 years since the world experienced a month that was colder than average.

The impacts of the rising heat on farming, food, water and human health have been studied closely for years, and the trends being played out now mirror those laid out years ago in projections by the bureau, the CSIRO and the Garnaut climate change review.

They include heightened bushfire risk, rising sea levels affecting infrastructure and houses all along the coast and, by the end of the century, massive cuts in food production in the Murray-Darling Basin.

According to a peer-reviewed study by the Australian-based Global Carbon Project, global average temperatures are on a trajectory to rise a further four to six degrees by the end of this century, with that rise felt most strongly over land areas.

It would be enough to tip Tuesday's 40C-plus temperatures over much of mainland Australia close to 50C in some parts.

"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 civilisation,'' said Liz Hanna, convener of the human health division at the Australian National University's climate change Adaption Network.

''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 Hanna said. ''The unparalleled setting of new heat extremes is forcing the continual upwards trending of warming predictions for the future, and the time scale is contracting.''

Around the world, this year could be the hottest ever recorded by modern instrumentation, according to a recent study by Britain's Met Office.

It said that, based on the rising background warming trend, this year would be 0.43 to 0.71 degrees hotter globally than the average temperature between 1961 and 1990, with a ''best fit'' of 0.57 degrees warmer. If that turns out to be accurate, this year would surpass the previous record, held jointly by 2005 and 2010.

The Met Office findings are considered telling in the climate science community, because this year is set to be a relatively ''neutral'' year, without a strong El Nino warming cycle to push up temperatures.

The current Australian heatwave, while exceptional, is a continuation of the record-breaking temperatures seen across much of Australia since September, according to the special climate statement issued by the bureau on Tuesday. The last four months of last year were the hottest on record, albeit by just 0.01 of a degree.

''This event is ongoing with further significant records likely to be set,'' the statement said.

The weather bureau's Dr Jones said the background warming was now clearly felt.

''Our oceans are hotter, the tropics are hotter, so any attempt to disentangle climate change from what we see in terms of weather doesn't make much sense - everything is hotter,'' he said.

EARLY BURN: Runners get out early to beat the head at Sydney's Bronte Beach.
EARLY BURN: Runners get out early to beat the head at Sydney's Bronte Beach.

''There is no alternative world which doesn't have the fingerprint of warming.''

- Sydney Morning Herald