(CNN) Thousands of activists are set to march across nine cities in Australia on Friday, singling out Prime Minister Scott Morrison for climate inaction amid a worsening fire crisis that has ravaged large swathes of the country.

The protests, organized by national student organization Uni Students for Climate Justice, will take place in cities including Melbourne, Sydney, Brisbane and Perth. Huge crowds are expected, with tens of thousands marking themselves as attending on Facebook -- indicating widespread public discontent after months of increasingly deadly fires

Morrison has faced heavy criticism for his climate policies and response to the fires. Several of Friday's protests are under the slogan "Sack Scomo."

A total of 27 people have died this fire season, and the blazes are nowhere near done -- Australia is only about halfway through its hot, dry summer. State and federal authorities have been scrambling to respond, with thousands of firefighters on the ground and billions of dollars allocated in federal aid. But climate activists say it's not enough.

"We're protesting this Friday because we're outraged about our government's criminal negligence about the bushfire crisis, exacerbated by climate change," said the group on its Facebook page . "We are protesting to give a voice to the tens of thousands of people who want real action on climate change and real funding for relief services."

Friday's protests will also push for five main demands: funding for firefighters, relief and aid for affected communities, land and water sovereignty for indigenous communities, an immediate transition toward renewable energy, and a "just transition" for workers in the fossil fuel industry.

A climate protest in Sydney, Australia, on December 19, 2019.

The biggest protest will likely be in Melbourne, where organizers are pushing forward despite authorities urging them to postpone due to dangerous fire conditions and limited resources.

"This week is not a time for public protest," said Victoria Police acting assistant commissioner Tim Hansen on Wednesday, adding that the force had formally asked organizers to move the protest time and date.

He said the police force was already stretched thin and fatigued, and the protests would be a "distraction" and a "resource drain" on a day forecast to be hot and dangerous.

Officers in Victoria are working on evacuations and preparations ahead of Friday, when temperatures are expected to spike -- but "now on top of this, we are distracted by having to provide extra resources to support a protest activity," Hansen said.

The organizers pushed back, posting on Facebook that the police were "trying to paint ordinary people -- who are fed up with their lies, theft and criminal negligence -- as being a drain on emergency services."

Public anger builds against Morrison

Morrison has faced growing anger and frustration from the public this month as the fires continue to spiral out of control.

During a visit last week to the fire-ravaged town of Cobargo, in New South Wales state, Morrison was heckled by furious residents who had lost their homes.

One woman said she would only shake his hand if he gave more funding to the NSW Rural Fire Service. "We need more help," she shouted after him as he walked away.

Another group was more explicit, cursing at him and saying, "You're an idiot."

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Morrison has been accused of not doing enough to address climate change, which experts say is making natural disasters like fires go from bad to worse. Summers in Australia are always hot and dry -- but fire seasons have been arriving earlier and spreading with greater intensity.

"The science is telling us ... these extreme heat conditions we've seen this year might occur naturally once every 350 years," said climate scientist and former federal climate commissioner Tim Flannery. "But once you add in the influence of the human-emitted greenhouse gases, we're likely to see those conditions once every eight years."

Flannery added that coal was "a national addiction," and the link between government and the fossil fuel industry was "almost complete."

Critics of the Morrison administration have pointed to his history of climate skepticism and support for coal mines. In 2017, Morrison -- then treasurer -- made his position clear when he brought a lump of coal into Parliament.

"This is coal. Don't be afraid, don't be scared," he said, to jeers from the opposition. "It's coal that has ensured for over 100 years that Australia has enjoyed an energy-competitive advantage that has delivered prosperity to Australian businesses."

Since then, his climate rhetoric has softened a little -- he has acknowledged the link between climate change and extreme weather, and asserted his commitment to reduce emissions. But he also said that the government would only pursue "sensible" policies, and that there wasn't "a single policy, whether it be climate or otherwise," that can fully protect Australia against the fires.

What the climate crisis means for Australia

The fires have been exceptionally bad this year because of severe weather -- extreme heat, dry conditions and ferocious winds that whip up the flames and spread embers far distances, which then start new blazes.

But the climate crisis in Australia goes far beyond the fires -- it has manifested in various forms, including the worst drought in living memory. The ongoing years-long drought has devastated farmers, whose very livelihoods are disappearing; images from the ground show cracked, barren land and skeletal cattle.

Heatwaves are also becoming more frequent and severe; one in December broke the record for highest nationwide average temperature, with some places measuring temperatures well above 40 degrees Celsius (about 113-120 degrees Fahrenheit). In 2018, one heatwave was so bad that flying foxes died by the thousands , falling out of their colonies in the trees.

Meanwhile, the UNESCO heritage-listed Great Barrier Reef, a 1,500-mile stretch that supports thousands of species, is slowly dying from heating oceans. It lost more than half its coral in two mass bleaching events in 2016 and 2017, and is losing its ability to recover and replenish.

These events have taken a huge toll on wildlife -- Australia has the highest rate of species loss of any area in the world. Animals in the country have dealt with natural catastrophes like fires for millennia, but human interference and climate change have changed everything.

"(The animals are) not coping, and now they've got no grass, no water, no habitat," said Janine Green, a volunteer at WIRES Wildlife Rescue. "Who knows if they can breed after this? We've never seen anything like this before."