2013 was hottest year on record in Australia, Bureau of Meteorology says

Updated

Australia has just sweltered through its hottest year on record, according to the Bureau of Meteorology.

Average temperatures were 1.20 degrees Celsius above the long-term average of 21.8C, breaking the previous record set in 2005 by 0.17C, the bureau said in its Annual Climate Statement.

All states and territories recorded above average temperatures in 2013, with Western Australia, Northern Territory and South Australia all breaking annual average temperature records.

And every month of 2013 had national average temperatures at least 0.5C above normal, according to the statement.

The country recorded its hottest day on January 7 - a month which also saw the hottest week and hottest month since records began in 1910.

A new record was set for the number of consecutive days the national average temperature exceeded 39C – seven days between January 2 and 8, 2013, almost doubling the previous record of four consecutive days in 1973.

The highest temperature recorded during 2013 was 49.6C at Moomba in South Australia on January 12, which was the highest temperature in Australia since 1998.

Further, with mean temperatures across Australia generally well above average since September 2012, long periods of warmer-than-average days have been common, with a distinct lack of cold weather, the statement says.

Nights have also been warmer than average, but less so than days.

The country has experienced just one cooler-than-average year in the last decade - 2011.

Australian temperatures have warmed approximately 1C since 1950, consistent with global climate trends.

Globally, each of the past 13 years since 2001 have ranked among the 14 warmest on record.

The bureau's Neil Plummer told News 24 that as a predictor of climate in Australia, the statistics "speak for themselves", and that a "consistent body of evidence" gathered globally pointed to a "warming trend".

"All Australian records go back to 1910. The trend over that period is a little short of a degree warming over that period, where most of the warming has occurred since around about 1950, and that's consistent with the global pattern," he said.

"It's not just us at the bureau doing the number crunching, it is all the bureaus around the world, and it is that body of evidence that we're all seeing a warming over Australia and a warming world."

According to the weather bureau's statement, significant climate events of 2013 included:

The January heatwave, which saw a number of severe bushfires in south eastern Tasmania and in Victoria, where bushfires were particularly widespread.

An early start to the fire season saw major bushfires in the Blue Mountains during October, the most destructive in the region since 1968.

Ex-tropical cyclone Oswald, which caused heavy rain and flooding along the east coast in late January, with many coastal areas from Sydney to Cape York receiving more than 200mm of rainfall in 24 hours, and Upper Springbrook in the Gold Coast hinterland receiving 1496mm in eight days.

Tropical cyclone Rusty was the most intense tropical cyclone to make landfall in 2013, causing flooding in the Pilbara and Western Kimberley in late February.

Tropical cyclone Alessia crossed the coast near Darwin in late November, the earliest tropical cyclone to make landfall in the Northern Territory in 40 years.

The statement concurred with a report released by the United Nations' climate panel in September, saying that recent warming trends had been "dominated by the influence of increasing greenhouse gases and the enhanced greenhouse effect".

According to the landmark Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report, scientists are 95 per cent sure that humans are responsible for global warming.

The report, the result of almost seven years' work by more than 600 scientists and researchers, says the concentration of carbon dioxide in the atmosphere has risen by 40 per cent since the pre-industrial era.

It presents a number of different scenarios of how climate change may unfold over the next century, but says the majority of climate models point to a mean temperature rise of around 2C.

University of New South Wales climate expert Dr Sarah Perkins says last year shows the effects of global warming are taking hold.

"It's here and now. We're actually starting to feel the effects, and even though the global temperature hasn't risen more than a degree at the moment, that's already had impacts on extreme temperatures and that's consistent with what we've been seeing for quite a while," she said.

Dr Perkins says record temperatures without the climatic influence of an El Nino makes 2013 especially significant.

"Usually when we have warmer than average temperatures and lower than average rainfall, that's associated with an El Nino summer," she said.

Australia has always been a country of extremes; we're no strangers to tropical cyclones or heatwaves or anything of the like, but it's the time they're occurring, particularly the start of the bushfire season this year. It was the earliest on record. That's what we're worried about. Climate expert Dr Sarah Perkins

"When we have La Nina summers, we have higher than average rainfall and lower than average temperatures.

"However, the past two summers have been neutral years, so they should have be effectively average rainfall and average temperature.

"So that's what we're a little bit worried about - that we're seeing all these records breaking when we're not really in a pattern of climate that influences those sorts of extremes.

"Australia has always been a country of extremes; we're no strangers to tropical cyclones or heatwaves or anything of the like, but it's the time they're occurring, particularly the start of the bushfire season this year. It was the earliest on record. That's what we're worried about."

Earth's oceans also heating up

According to the bureau, the planet's oceans are also getting warmer, with sea surface temperatures over the past 10 years the warmest on record.

Mr Plummer said the waters around Australia were no exception.

"In fact the waters to the south of Australia were the warmest on record, too, so it's that consistent body of evidence, particularly since the 1950s, where we've seen quite a strong warming," he said.

In 2013, sea surface temperatures around Australia were "unusually warm throughout the year", according to the bureau statement, with the temperatures for January and February among the highest on record.

Surface temperatures off the western and southern coast of Australia from summer 2012–13 until May were "consistently very much above average," the bureau says.

Global temperatures on the rise

In an analysis of the BoM Annual Climate Statement written for the The Conversation website, bureau experts said that 2013 was the 6th hottest year on record globally, while 13 of the 14 hottest years on record have occurred since 2001.

As of the end of November, global temperatures were 0.49C above average, the authors said, adding that other parts of the world to experience their warmest year on record in 2013 included the tropical North Pacific region around and east of the Philippines, along with parts of central Asia.

Exceptionally warm sea temperatures in the western North Pacific had "contributed to a very active tropical cyclone season in the region, especially in October and November", they wrote.

"In those months there were seven super typhoons (the equivalent of a category 4 or 5 tropical cyclone in Australia) in as many weeks," they wrote, adding that the most significant of these was Typhoon Haiyan, which they described as one of the most intense tropical cyclones ever to make landfall.

Heat defines first days of 2014 as Australia swelters

Extreme conditions have persisted into the first days of 2014, with soaring temperatures in areas extending from Queensland's interior to Central Australia, northern South Australia and north-western New South Wales.

On Thursday, temperature records tumbled in central, western and north-west Queensland, with the mercury topping 40C in a number of areas.

Friday saw another searing day for parts of central and western Queensland, with St George reaching 47.2C.

Northerly winds will push the heat towards the state's south-east over the next few days. Brisbane is expected to reach a high of close to 40C on Saturday.

South Australia's far north also sweltered through near-record temperatures on Thursday, as ex-tropical cyclone Christine tracked across the state, bringing high winds.

John Nairn from the weather bureau says several outback towns had temperatures well into the 40s.

"Our temperatures have been near record, the highest temperature we had was at Moomba at 49.3 degrees but a lot of centres up there are pushing up around that 50 mark," he said.

The full Bureau of Meteorology Annual Climate Statement report can be viewed online here.

Topics: weather, climate-change, australia

First posted