These buzzwords - used by global leaders, activists and experts alike - have appeared so regularly in podium speeches and press conferences that the crowds at the U.N. conference often break out into giggles.

Two of the most common are "North Star" and "science" - which COP28 President Sultan al-Jaber uses to describe his guiding principles at the summit - limiting the global temperature rise to 1.5C above the preindustrial average.

"My job and this mission is to ensure that ... we stay laser-focused on our North Star, and that is keeping 1.5 within reach," he told the summit on Monday.

"If anything you will only see my North Star more shining, because that's how much I care about keeping focus on my North Star."

'NORTH STAR'

The North Star cannot be seen by those living in the Southern Hemisphere, but nevertheless the concept of the North Star as a guide towards climate change goals has caught on at the conference.

U.S. climate envoy John Kerry showed he was a fan during a press conference on Wednesday, as did Norwegian minister Espen Barth-Eide in a speech to the summit on Saturday. Their North Star references drew titters as the jargon-heavy conference rumbled on.

U.N. climate Chief Simon Stiell on Friday even promised a rocket of climate-friendly economic policies to take the summit toward the North Star.

Out and about in the Dubai COP28 venue, delegates were hoping that repeating the phrase might help to hammer home the message to the wider world.

"The way the human brain works, if you repeat a phrase over and over and over and over and over again ... the message goes through," said Clifford Gonzalves Bastille, a delegate from the Seychelles.

THE 'SCIENCE'

If 1.5C is the COP28 North Star, then "science" is the way to get there, based on this year's COP lexicon.

"Follow the science and help keep 1.5 degrees Celsius alive," Kerry told the Wednesday press conference, in which he made at least 10 more similar references.

Barbados Prime Minister Mia Mottley, campaigning to eliminate methane emissions, said the message from "the science must be simple to turn down the heat."

Britain's PM Rishi Sunak said "the climate science and mounting evidence of climate-related disasters show that we're not moving quickly or effectively enough."

But "science" can mean different things to different people.

"When we say 'follow the science,' everyone has a different interpretation," said Killian Abellon an observer at the conference with World YMCA.

"Some people are going to use it as a buzzword to convince us that their technological solutions are following the science," Abellon said. "The technology is going to buy us some time for sure, but it's not going to be enough."

According to the science.

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