World must rapidly cut emissions or see nearly 3 C warming

As global temperatures and greenhouse gas emissions smash records, UN climate scientists have warned current emissions pledges have the world on track to soar past temperature limits agreed to stop the worst effects of climate change.

The UN's annual Emissions Gap Report found that under measures pledged by states signed up to the Paris Agreement, humanity will likely see global average temperatures of between 2.5 and 2.9 degrees Celsius (4.5 to 5.22 Fahrenheit) above pre-industrial times by the end of the century.

Pledges to reach net-zero are not "considered credible," with none of the G20 countries cutting emissions quickly enough to meet those targets. The likelihood of reaching targets and "limiting warming to 1.5 C is only 14%," according to the report.

Predicted 2030 greenhouse gas missions must be cut by 42% to have a chance of staying within the 1.5 C threshold and avoid even more catastrophic extreme weather as well as potentially irreversible climate change effects.

The report called on world leaders to seriously up their climate ambitions to narrow the emissions gap at this year's UN climate conference (COP28) taking place in Dubai in December.

"There is no person or economy left on the planet untouched by climate change," said Inger Andersen, executive director of the United Nations Environment Programme (UNEP) in a statement. "We must instead lift the needle out of the same old groove of insufficient ambition and not enough action, and start setting other records: on cutting emissions, on green and just transitions and on climate finance."

CO2 emissions need to be cut rapidly

Global warming is caused largely by the greenhouse gas emissions released through burning fossil fuels such as coal, oil and gas. In 1850, CO2 concentrations in the atmosphere were at about 288 parts per million (ppm) but that has grown to 422 ppm today as a result of industrialization.

The average global temperature has increased with CO2 concentration and is now at 1.2 degrees Celsius above pre-industrial levels. This year is on track to be the hottest ever recorded.

To keep to the 2 degrees Celcius Paris Agreement goal, predicted emissions from greenhouse gases like methane, CO2 and nitrous oxide, more commonly known as laughing gas, would need to fall by 28%. 

According to the report there has been some progress. For example, when the Paris Agreement was adopted in 2015, emissions in 2030 were projected to increase by 16%. That figure has been cut to 3%.

But it's not enough to stop catastrophic extreme weather like that already being felt today, report leader author and senior advisor to CONCITO, Denmark's Green Think Tank, Anne Olhoff told DW.

"We're seeing droughts, we're seeing wildfires, and we're seeing that people are suffering. Basically, people are dying. People are being displaced in many places. So, all of that will become much, much worse that we know for sure," said Olhoff, adding that temperatures in certain regions could be twice as high as the global average.

"If it's 6 or 7 degrees warmer in certain parts of Africa ... it might actually make it impossible to live or to stay living where you're living currently," she said, adding that countries must act swiftly and decisively now "in terms of keeping 1.5 degrees alive."

It's not impossible to get back on the 42%-emissions-reduction track, but the world has "quite a massive task ahead," Olhoff continued.

Coal, oil and gas reserves must stay in the ground

To keep to agreed temperature targets, the world has to rapidly cut emissions from fossil fuels. The report shows that if the oil from all existing and planned oil fields were extracted and burned, the world would blow past the 1.5 C limit. It would be impossible to keep within the 2-degree threshold if all planned gas and coal reserves were also burned.

The good news is, according to the report, that renewable energy like solar and wind have been seeing rapid expansion. In China, for instance, non-fossil energy "surpassed 50% of all installed capacity, reaching a 2025 milestone target early."

"We have many proven technologies. They are cost-effective and competitive with fossil fuels. They just need to be deployed at an unprecedented pace and scale," said lead author Olhoff.

According to the report, green energy will not only bring cleaner air and slow climate change, but also "considerable opportunities to low- and middle-income countries" including new revenue for industry and jobs for the public. 

That's why it's important that poorer countries get support from wealthier nations to "accelerate the green transition and bring down the cost of capital," Olhoff said.

Sucking CO2 from the atmosphere to reach climate targets

In addition to phasing out fossil fuels and rapidly expanding renewables, the world needs additional methods to remove CO2 from the atmosphere to stay within temperature limits.

Reforestation, afforestation (turning an area where there were previously no trees into a forest) and forest management remove around 2 billion tons of CO2 from the atmosphere yearly, according to the UN report. That figure needs to be tripled by 2050 for the world to be climate neutral.

The report also recommends the expansion of newer methods of CO2 removal,such as direct air carbon capture and storage technology which involves sucking CO2 out of the atmosphere and storing it deep underground.

Another option is creating biochar, a form of charcoal made from biomass such as wood and agricultural waste. This binds CO2 and can be added to soil, increasing fertility and helping to minimize droughts by slowing water run-off.

The authors predict such methods could see an additional 4 billion tons of CO2 removed from the atmosphere annually by 2050.

At the same time, they warn against seeing CO2 removal as a panacea. Afforestation and reforestation would compete with land for producing food and some of the other technologies are still in development. And they cannot replace the phasing out of fossil fuels.

"The latest Emissions Gap Report 2023 presents a chilling reality," said Harjeet Singh, head of global political strategy at Bonn-based NGO Climate Action Now in a statement. "The time for bold, decisive action is now — anything less is a betrayal to current and future generations."