Australia's hottest-ever year, and Canberra's second-hottest year on record, could have been even worse were it not for neutral El Nino conditions and early monsoons, according to weather experts, one of whom described 2013's extremes as "freakish".
And after a hotter and drier-than-usual December, Canberra's fire services are geared up for a potentially dangerous month to come as the outlook for January predicts a higher chance of dry conditions.
For Canberra, 2013 narrowly missed being the city's hottest year on record, with an average temperature across the year of 21.7 degrees - just .05 degrees cooler than the record-breaking 2006.
Around the country, all capital cities recorded temperatures in their top-10 hottest for the year. Sydney and Adelaide sizzled through their hottest years ever. Despite "blitzing" hot weather records, University of NSW climate expert Sarah Perkins said 2013's heat was not a surprise after a pattern of more heat extremes and fewer cold-weather records over the past three decades.
Dr Perkins said the multitude of records broken in 2013 (hottest year, hottest month, hottest day) was made extraordinary by the fact that the El Nino Southern Oscillation index was neutral, with no tendency for the hotter, drier weather typically associated with El Nino summers.
"The last two summers have both fallen as neutral summers, and we've seen quite record-breaking conditions. So if we were to have an El Nino year in one of these two summers it certainly would have seen more amplified extremes," she said. "If it weren't for human-induced climate change, occasionally a record would be broken here or there, but you certainly wouldn't get nearly as many in one year. That's a very freakish thing to have."
While a single hot year did not amount to strong evidence of climate change, she said it would likely be pointed to by climate scientists as "another link in the chain".
"I don't think it can be used as the one and only year or to say 'look at this hot year, it's all due to human-induced climate change'. It's very difficult to nut out the exact contribution of human-induced climate change to this year … or to any of the records we saw broken this year.
"But the more years we see like this, the more records we see broken, the stronger the argument is."
According to meteorologist Rob Sharpe from Fairfax-owned Weatherzone, the heat leading into December was also moderated slightly by an earlier-than-usual monsoon in the north and centre of the country, while tropical cyclone Christine, off the West Australian coast, would temper heat in central Australia further still - but not before it pushed hot air towards the east coast first.
"It's quite hot at the moment, but as tropical cyclone Christine becomes ex-TC and comes across - because it's going to move across with a lot of cloud … it's going to reduce the heat in the nation for the next little while - it will be another few weeks before we see the air mass getting super hot again,'' he said.
Canberra finished 2013 with a string of five days above 30 degrees, which looked set to continue into the start of 2014. All up in December, the ACT had 14 days over 30degrees, double the historical average of seven, and recorded just 23 millimetres of rain at the airport.
‘‘It’s going to start fairly warm in Canberra with that heat moving in ahead of ex-TC Christine. So from [Tuesday] until Friday all those days are likely to hit 30, and then over the weekend it will cool down a bit, and there might be about a week of near-average temperatures actually, and then we’ll see some more heat pushing in,’’ Mr Sharpe said.
Emergency Services Commissioner Dominic Lane said it was shaping up to be a month of potentially severe bushfire risk for the capital region.
‘‘We’ve seen that manifesting itself at the moment with the grass across the ACT region now curing to the point where it’s very flammable,’’ he said.
Commissioner Lane said 2013 was a successful year for the agency, in which it helped Canberra through catastrophic fire risks in January, conducted record amounts of hazard reduction through autumn, and boosted its volunteer ranks in the Rural Fire Service to a record 580 members.
While he was confident the ACT was well prepared for the rest of summer, he warned Canberrans to be wary of potentially dangerous fire conditions.
‘‘Whilst people are holidaying and camping ... I urge them to use extreme caution, and obey the regulations,’’ he said.