This article is more than 9 months old

This article is more than 9 months old

Sydney disappeared behind a thick layer of bushfire smoke that blanketed the city and pushed air quality 11 times higher than considered “hazardous” on Tuesday, while Australia’s weary firefighters faced what authorities warned were the potentially “lethal” combination of high temperatures and heavy winds.

Across Sydney, buildings were evacuated regularly as fire alarms were triggered at random. During the morning commute, the sound of the ferries using their fog horns due to the poor visibility filled the area surrounding the harbour before the entire fleet was finally grounded.

Schools kept children inside during their lunch break and face masks became a regular accoutrement as Sydney’s landmarks were lost in the haze.

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Images of the Opera House, Harbour Bridge and Bondi Beach shrouded in smoke were shared widely on social media as the usual joie de vivre that greets the beginning of summer in this city gave way to anxiety over the lengthening bushfire crisis.

A domestic cricket match between New South Wales and Queensland continued under a pall. Footage of the former Australian test player Steve O’Keefe bowling spin in near darkness seemed to sum up the uncanny feeling that settled across the city.

cricket.com.au (@cricketcomau) Through the Sydney smoke, Steve O'Keefe wrapped up Queensland's tail with a couple of beauties - and he was PUMPED! #SheffieldShield pic.twitter.com/54asVNZco0

Former Oasis frontman Liam Gallagher, in town as part of an Australian tour, reflected it better than most: “Sydney looks spooky as fuck with all this smoke proper shitting it,” he wrote on Twitter.

Liam Gallagher (@liamgallagher) Sydney looks spooky as fuck with all this smoke proper shitting it LG x

A NSW Ambulance superintendent, Brent Armitage, said paramedics were attending up to 100 respiratory-related call-outs per day and the state’s health department warned residents to stay indoors as much as possible amid “unprecedented” smoke pollution.

The state’s director of environmental health, Dr Richard Broome, said the smoke in Sydney was “some of the worst air quality we’ve seen”.

“Certainly in Sydney we have experienced very poor air quality episodes in the past and the one I’m most aware of is the 2009 dust storm episode where we had extremely high levels, but certainly this smoky period we’ve been experiencing for the past month or so, it is unprecedented, so these conditions are a risk to people’s health,” Broome said.

ANDREW THOMAS (@andthomsydney) Antonio and Paula’s wedding day - in front of the most iconic backdrop in #sydneysmoke pic.twitter.com/jRwm32EqmA

Buildings across the city had to be evacuated so regularly that the assistant commissioner of NSW Fire and Rescue, Roger Mentha, was forced to warn actual victims of fire not to rely on automatic alarms.

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Mantha said crews had responded to more than 500 automatic fire alarms across the city.

“This amount of calls peaked between 11am and 12 midday with 154 automatic alarms, as a result there’s also been over 335 triple-zero emergency calls,” he told reporters in Sydney.

Mentha said the volume of calls was unprecedented and had increased as the smoke cloud “descended on the city”.

Among those forced outside were the headquarters of the Rural Fire Service and one of the city’s major newspapers, the Sydney Morning Herald.

Fires have continued to burn throughout the eastern states, and in particular NSW, for the better part of a month with no reprieve in sight.

Six people have died, almost 700 homes have been destroyed and at least 2.7m hectares have burned. Fires stretch the distance of the NSW coastline. Drought has gripped this part of Australia for several months and some coastal towns face the possibility of running out of water by January if summer rains fail to materialise.

Tuesday had been labelled a potentially “lethal” day by the commissioner of the RFS, Shane Fitzsimmons, as 40C degree temperatures and hot gusty winds whipped up flames.

More than 80 fires were burning across NSW on Tuesday, while firefighting crews in Victoria and Queensland are also battling a number of blazes.

On Tuesday evening, a fire burning on the state’s central coast, the Little L Complex fire, was upgraded to an emergency level, and was 67,000 hectares in size and uncontained.

One fire at Gospers Mountain, north of Sydney, has already burned through some 319,000 hectares. The fire has burned steadily for weeks, and previously merged with other blazes to form one long sweeping fire-front.

Further north, residents in isolated bush communities in the state’s Hunter Valley became ringed by fire and were expected to be completely cut off.

With no obvious end – other than rain – to the crisis, the state’s former fire chief Greg Mullins warned on Tuesday that firefighters may have “nothing left in the tank” as they battle with an abnormally long and extensive fire season.

“Everyone is getting pretty worn out and, in my experience, that’s where all the bad stuff happens,” he told AAP. “The troops, if they’re worn out, you get to a stage where it just overwhelms everyone, so that’s a worry.

“I’m buggered ... and I haven’t done as many [shifts] as some people. People will step up. Firefighters – they are men and women who give their all – they will do whatever is asked of them and more but I do fear for their welfare.”