One of the Canadian co-authors of Sunday's gloomy report on climate change says the world is at a "critical juncture" if it is to avoid a potentially devastating rise in temperatures — and that fossil-fuel megaprojects planned for B.C. are a step in the wrong direction.

Kirsten Zickfeld, an associate professor in geography at Simon Fraser University, was one of two Canadians selected to author the report, along with dozens of experts around the world.

"For certain people, it is a life-or-death situation," she told guest host Margaret Gallagher on CBC's On The Coast.

"I think the biggest takeaway is the urgency. We're at a critical juncture. We really only have a few years to turn things around."

Preventing an extra single degree of heat could make a life-or-death difference in the next few decades for multitudes of people and ecosystems on this fast-warming planet, the Nobel Prize-winning Intergovernmental Panel on Climate Change announced Sunday.

In the 728-page document, the UN organization detailed how Earth's weather, health and ecosystems would be in better shape if the world's leaders could somehow limit future human-caused warming to just 0.5 C from now, instead of the globally agreed-upon goal of 1 C.

Intergovernmental Panel on Climate Change chair Hoesung Lee, centre, speaks during a news conference in Incheon, South Korea. (Ahn Young-joon/Associated Press)

Canada alone would not be able to limit warming to 0.5 C, Zickfeld said. The country emits 700 million tonnes of carbon dioxide per year and is one of the highest emitters per capita in the world.

She said federal and provincial actions such as greenlighting the $40-billion LNG project, pushing for the Trans Mountain pipeline expansion and softening carbon pricing are all inconsistent with the report's recommendations.

"If we do not tackle climate change, the damages would outweigh any losses that we have from addressing it," Zickfeld said.

The report concluded that if human-caused warming could be limited to just 0.5 C, among other things:

Half as many people would suffer from lack of water.

There would be fewer deaths and illnesses from heat, smog and infectious diseases.

Seas would rise nearly 10 centimetres less.

Half as many animals with backbones and plants would lose the majority of their habitats.

There would be substantially fewer heat waves, downpours and droughts.

The West Antarctic ice sheet might not kick into irreversible melting.

And it just may be enough to save most of the world's coral reefs from dying.

Limiting warming to 0.5 C from now means the world can keep "a semblance" of the ecosystems we have, according to report.

But meeting the more ambitious goal of slightly less warming would require immediate, draconian cuts in emissions of heat-trapping gases and dramatic changes in the energy field. While the UN panel says technically that's possible, it saw little chance of the needed adjustments happening.

Residents sleep on pavement to escape heat and frequent power outages in Karachi, Pakistan, in May. Deadly heat waves that hit India and Pakistan in 2015 could become practically yearly events, the report warns. (Akhtar Soomro/Reuters)

In 2010, international negotiators adopted a goal of limiting warming to 2 C since pre-industrial times. It's called the two-degree goal.

In 2015, when the nations of the world agreed to the historic Paris climate agreement, they set dual goals: 2 C and a more demanding target of 1.5 C from pre-industrial times. The 1.5 C was at the urging of vulnerable countries that called the two-degree goal a death sentence.

The report is seen as the main scientific guide for government policymakers on how to implement the 2015 Paris Agreement during the upcoming Katowice Climate Change Conference in Poland in December.

The world has already warmed 1 C since pre-industrial times, so the talk is really about the difference of another half-degree from now.

More than 90 scientists wrote the report, which is based on more than 6,000 peer reviews.

Watch: Why BBC stopped interviewing climate change deniers

With files from The Associated Press, Reuters and CBC News

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