The French President Emmanuel Macron is making it his mission to convince the most powerful world leaders that climate change is real and that it presents an imminent global crisis.

Shortly after addressing the United States Congress on why President Trump should not withdraw from the Paris accord, Macron made his way to Australia.

Speaking at the Sydney Opera House in front of a crowd of politicians, business leaders and French expats, Macron made a similar argument.

The French President urged Australia's Prime Minister Malcolm Turnbull to show "the power of conviction" and lead the way in the fight against climate change – never mind the resistance he may face from Parliament and his party.

"I am fully aware of the political and economic debate surrounding this issue in your country, and I respect this," Macron said.

"But I think that actual leaders are those that can respect those existing interests, but at the same time decide to participate to something broader, to something more strategic."

Drawing on the power of proximity, the French president argued that Australia's closest neighbors will be some of the first to feel the dangerous effects of climate change.

"When I speak about vulnerability, I want to speak obviously about climate, which is an absolute priority," Macron said.

"Numerous states in the Pacific are at direct risk of disappearing completely in only a few years if we do not take action."

To be clear, Prime Minister Turnbull isn't exactly a climate denier – at least not like President Trump - but he isn't what you would call a shining beacon for climate activists, either.

In fact, Turnbull's inaction on climate change has led some to describe him as a "de facto climate denier."

Before his election, Turnbull promised that he would never lead a political party that didn't take climate change seriously, though many critics argue that since taking power that is exactly what the Prime Minister has done.

As Macron correctly pointed out in his speech, the Prime Minister's climate inaction has likely been due to political pressure.

According to the Institute of Public Affairs, a think tank that rejects climate science, more than half of the Coalition's parliamentarians are currently climate skeptics.

And while it's true that the Australian government just announced they would be spending 500 million Australian dollars on protecting the Great Barrier Reef, very little action has been taken to mitigate the underlying problem.

"Science is well aware of what is killing coral on the Great Barrier Reef — it's the excess heat that comes from burning fossil fuels," Bill McKibben, the founder of 350.org, told The New York Times.

"If the Turnbull government was serious about saving the reef, they would be willing to take on the industry responsible for the damage."

Talking to RenewEconomy, McKibben pointed out the folly of Australia's decision.

"It's like coming across someone who has been mugged in a dark alley and you offer them a cholesterol test. It doesn't address the problem," he said.

The decision does appear slightly hypocritical given the Turnbull government's continued support for the controversial Adani coal mine, which scientists say would have a deleterious effect on the reef.

"To simultaneously promote Adani's coal mine, which would be one of the world's largest, pretending to care about the world's largest Reef is an acrobatic feat only cynical politicians would attempt," McKibben told The New York Times.

McKibben finds Turnbull's lack of action on climate change particularly worrying.

"Turnbull knows everything there is to know about climate change, but doesn't do anything about it," he told RenewEconomy.

"I don't know if that if that makes him worse than Trump or better."

Clearly, Macron has similar fears. After speaking out against President Trump's stance on climate change, Prime Minister Turnbull was Macron's second target.

But while Macron faces an uphill battle when it comes to changing the mind of a stubborn climate denier like Trump, he might stand a chance with Turnbull.

By acknowledging the political pressure that Turnbull is facing from a party steeped in climate denial, Macron may have won himself over an ally in the global fight against climate change.

After the event, Turnbull heaped praise on the foreign visitor.

"You are a man who is for, not against," Turnbull said.

"We might say 'always on the front foot, always a glass half full, not half empty'."

Perhaps Turnbull will follow Macron's lead and begin standing for climate change - instead of standing idly by while others in his party stand against it.