This article was written by Seth Borenstein and was published in the Globe & Mail on November 21, 2023.

Earth is speeding to 2.5 to 2.9 degrees Celsius of global warming since preindustrial times, set to blow well past the agreed-upon international climate threshold, a United Nations report calculated.

To have an even money shot at keeping warming to the 1.5 degree limit adopted by the 2015 Paris climate agreement, countries have to slash their emissions by 42 per cent by the end of the decade, said the UN Environment Programme’s Emissions Gap report issued Monday. Carbon emissions from the burning of coal, oil and gas rose 1.2 per cent last year, the report said.

This year Earth got a taste of what’s to come, said the report, which sets the table for international climate talks later this month.

Through the end of September, the daily global average temperature exceeded 1.5 degrees above mid-19th century levels on 86 days this year, the report said. But that increased to 127 days because nearly all of the first two weeks of November and all of October reached or exceeded 1.5 degrees, according to the European climate service Copernicus. That’s 40 per cent of the days so far this year.

On Friday, the globe hit 2 degrees above preindustrial levels for the first time in recorded history, according to Copernicus deputy director Samantha Burgess.

“It’s really an indication that we are already seeing a change, an acceleration,” said report lead author Anne Olhoff of Denmark’s climate think tank Concito. “Based on what science tells us, this is just like a whisper. What will be in the future will be more like a roar.”

It’s dangerous already, said UNEP director Inger Andersen.

“Temperatures are hitting new heights, while extreme weather events are occurring more and more often, developing faster and becoming much more intense,” Ms. Andersen said. The new report “tells us that it’s going to take a massive and urgent shift to avoid these records falling year after year.”

The 1.5-degree goal is based on a time period measured over many years, not days, scientists said. Earlier reports put Earth reaching that longer term limit in early 2029 without dramatic emission changes.

To keep that from happening, the countries of the world have to come up with more stringent goals to cut emissions of carbon dioxide and implement policies to act on those goals, Ms. Olhoff said.

In the past two years only nine countries have come up with new goals, so that hasn’t moved the needle, but some countries, including the United States and those in Europe, have put policies in place that slightly improved the outlook, she said.

The United States’ Inflation Reduction Act, which has US$375-billion in spending on clean energy, by 2030 would reduce yearly emissions of carbon dioxide by about 1 billion tonnes, Ms. Olhoff said.

That sounds like a lot, but the world in 2022 spewed 57.4 billion tonnes of greenhouse gases. Current country pledges would trim that to 55 billion tonnes, and to limit warming to the 1.5 degree mark emissions in 2030 have to be down to 33 billion tonnes. That’s an “emissions gap” of 22 billion tonnes.

United Nations Secretary-General Antonio Guterres said “the emissions gap is more like an emissions canyon – a canyon littered with broken promises, broken lives and broken records.”

That’s why the report said the chance of keeping warming at or under 1.5 degrees is about one-in-seven or about 14 per cent, “very, very slim indeed,” Ms. Olhoff said.

If the world wants to settle for a warming limit of 2 degrees – a secondary threshold in the Paris agreement – it only has to trim emissions down to 41 billion tonnes, with a gap of 16 billion tonnes from now, the report said.

Because the world has already warmed nearly 1.2 degrees since the mid-19th century, the report’s projections would mean another 1.3 to 1.7-degree warming by the end of this century.

For two years countries have known they have to come up with more ambitious emission cuts targets if the world wants to limit warming to 1.5 degrees, but “none of the large emitters have changed their pledges,” said study co-author Niklas Hohne, a scientist at the New Climate Institute in Germany.

That’s why for the past few years the grim outlook from annual Emissions Gap reports barely changed, Ms. Olhoff said.