As a thick pall of smoke descended on Sydney this week, obscuring the Opera House from view, staining harbour beaches black with ash and lifting air pollution to "hazardous" levels, an estimated 20,000 protesters marched from Town Hall to Hyde Park demanding stronger action on climate change. Prime Minister Scott Morrison urged calm on Thursday, speaking more directly than previously about the connection between bushfires and global warming - and acknowledging the "national disaster" unfolding across the east coast. Loading Replay Replay video Play video Play video "I can understand that it's deeply unsettling to a lot of Australians, particularly those who are living in Sydney," he said. The "country is coming together to deal with the firefighting challenge that we have", he said, reiterating that climate change "along with many other factors" had contributed to the fires.

Morrison said global warming was a challenge for the international community and his government was doing its share. Loading On the other side of the world, Taylor announced to the UN climate negotiations that Australia was on track to "meet and beat" its Paris emissions-reduction targets. The Paris climate agreement ties the 185 signatory countries to individual emissions reduction to 2020, and commits them to a long-term goal of limiting global warming to as far below 2 degrees Celsius as possible, and achieving net zero emissions by 2030. Morrison has argued Australia is only a small contributor to global emissions and therefore global action is needed to address the climate change factors exacerbating the fire risk. "To suggest that with just 1.3 per cent of global emissions that Australia doing something differently, more or less, would have changed the fire outcome this season, I don't think that stands up to any credible scientific evidence at all," Morrison said in November. What he didn't explain this week is why, given he acknowledges the role climate change is playing in increasing bushfire risks and Australia's reliance on global action to curb global warming, Taylor didn't call on the international community for greater emissions reduction to tackle the issue.

Former NSW Fire and Rescue commissioner Greg Mullins is calling on governments to show "moral leadership" to reduce the impacts of global warming. "Morally, as an Australian, I am proud of how the country took a leadership position on apartheid, global nuclear disarmament and in the world wars," he says. Loading "Did we say back then 'we are only a small part of the global effort?' No. Our government and our people said 'this is a threat to our existence and we need to speak up', even though it made some other countries angry. But on climate change we are gutless. After a 39-year career of public service, Mullins, who joined the Climate Council advocacy group last year, has emerged as an unlikely agitator for change. He is an outspoken critic of Australia's climate change policies, but praised NSW Environment Minister Matt Kean, who this week said the current situation was "not normal and doing nothing is not a solution", and committed the state to lowering greenhouse gases by 35 per cent on 2005 levels by 2030. "NSW has shown a lot of leadership. Those in Canberra are recalcitrants but some ministers are breaking ranks, which is great," Mullins says. "[Australia's] policies are totally irresponsible and show a lack of leadership and knowledge. When I was a senior public servant I had to make evidence-based decisions and I expect the same of our politicians."

Business groups are also disappointed by the government's lack of response. Investor Group on Climate Change chief executive Emma Herd says businesses and investors "have recognised the inevitability of a zero-carbon emissions economy" and are calling on the federal government for "policy certainty". The UN climate talks kicked off this week with a statement from institutional investors calling on governments around the world to phase out thermal coal power worldwide, put a price on carbon, end subsidies for fossil fuels, and strengthen commitments to Paris targets. "It was signed by 611 investors with an eye-watering $37 trillion in assets," Herd says. "There is an extreme sense of frustration across the business and investment community. Hard decisions are being made harder by the lack of clarity around what we're seeing from politicians, and that's why we're hearing so many business voices calling for policy clarity." Herd says despite her disappointment at the lack of government leadership, she is optimistic the business community is taking significant steps to deal with the impacts of climate change.

A "key enabler" is the work of the Financial Standards Body, an initiative of the G20 group of major economies, to establish a new standard for climate change-related financial risk disclosures. "I find it weird to say an accounting standard is going to change the world. But it's not just me, it's what ASIC [the Australian Securities and Investments Commission] and APRA [the Australian Prudential Regulation Authority] have been pushing for," she says. Loading "When you have the data around assets, countries and companies, you change the way you allocate capital, it changes the way you assess risks, and it ultimately changes the economy." But back on the frontline, Mullins says climate change has made it "far more dangerous" for firefighters and it "terrifies me". "Fuels loads are drier now. Typically fire would run through and burn anything with below a 10-millimetre diameter," he says. "But because it's so dry it's gone up to 15mm that will all burn, that's a 50 per cent increase in the fuel to generate heat, and that means you can't put these intense fires out.

"Thank God no one has been killed or seriously injured fighting fires this year. They will put themselves in harm's way on the front line and that's what keeps you awake at night, dreading the news one of your troops is injured." Loading With months left to run of bushfire season, those outside the Coalition are certain to increase their calls on Morrison to commit to more ambitious targets to reduce emissions. The Nationals and Liberals, however, have no consensus on deeper reductions and Morrison shows no signs of changing course. Whether the sheer scale of this crisis changes these political factors is yet to be seen. "Even people from the bush, who weren't sure about this climate change stuff, are saying they've never seen it like this before, their grandparents had never seen it like this before. People in Sydney trying to breath in the smoke are saying it wasn't this bad in the 1994 fires," Mullins says.