If the world continues to burn fossil fuels at the current rate, it is unlikely to be below the internationally agreed global warming limit just over five years from now – early 2029, a new study says. The study brings the world three years closer to the date it will reach a critical climate threshold that has increased by 1.5 degrees Celsius (2.7 degrees Fahrenheit) since the 1800s.
In addition to rising temperatures, disaster risks are also increasing; The world could lose most of its coral reefs, a significant ice sheet could begin to melt irreversibly, and deaths from water shortages, heat waves, and extreme weather could rise dramatically. Preliminary scientific report of the UN.
This threshold will be reached sooner than initially thought because the world has made progress in cleaning up another type of air pollution: tiny particles of smoke called aerosols. The study’s lead author said aerosols slightly cool the planet and mask the effects of burning coal, oil and natural gas. So, although cleaning up aerosol pollution is a good thing, this success means temperatures will rise a little more.
The study, published Monday in the journal Nature Climate Change, It calculates the so-called “carbon budget” – how much fossil fuels the world can burn – and still has a 50% chance of limiting warming since pre-industrial times to 1.5 degrees Celsius. This is the threshold set by the 2015 Paris Agreement.
The last 10 years were already an average of 1.14 degrees Celsius (2.05 Fahrenheit) warmer than the 19th century. Last year was 1.26 degrees Celsius (2.27 degrees Fahrenheit) warmer and this year will likely be warmer than that, scientists said.
A new study puts the carbon budget at 250 billion metric tons. The world is burning just over 40 billion tonnes of fuel per year (and rising) with six years to go. However, according to the study, these six years started in January 2023, meaning there are only five years and a few months left.
“It doesn’t mean the fight against climate change will be lost in six years, but I think we’ll probably be too late to fight the 1.5C limit unless we’re already in a strong downward spiral,” the Labor leader said. By Robin Lamboll, climate scientist at Imperial College London.
Lamboll said that the 2021 report of the UN Intergovernmental Panel on Climate Change shows a budget of 500 billion metric tons and a target of fixing 1.5 degrees by mid-2032. IPCC report co-chair and climate scientist Valerie Masson-Delmott said an update by most of the IPCC authors this June resulted in a similar carbon budget to Lamboll’s team, but Lamboll’s analysis was more detailed.
The biggest change to this year’s research compared to the 2021 report is that the new research shows a greater reduction in aerosol emissions from wildfires, sea salt spray, volcanoes and fossil fuel burning, which results in carbon monoxide that slightly cools the planet. covers greenhouse gases with greater impact. As the world cleans up carbon emissions, it also reduces the amount of refrigerant aerosols, Lamboll said, and the study takes that more into account, as do changes in computer modelling.
While the carbon budget is likely to end in early 2029, that doesn’t mean the world will instantly become 1.5 degrees warmer than pre-industrial levels. Lamboll said the real temperature shift could happen a little sooner, in a decade or two, but that will happen when the budget runs out.
The authors say people should not misunderstand the 1.5 degree budget loss as the only time left to stop global warming. According to their research, the carbon budget with a 50% chance of keeping warming below 2 degrees Celsius (3.6 Fahrenheit) is 1,220 billion metric tons, or about 30 years.
“We don’t want this to be seen as six years to save the planet,” said study co-author Christopher Smith, a climate scientist at the University of Leeds. “If we can limit warming to 1.6 degrees, 1.65 degrees or 1.7 degrees, that’s much better than 2 degrees. We still have to fight for every tenth of a degree.”
“A breach of 1.5 degrees doesn’t push the world over the edge at this point, but it’s a very significant turning point in increasing risk,” said climate scientist Bill Hare of Climate Action Tracker, which tracks national efforts to reduce carbon emissions. a catastrophic change”. .”
As climate talks begin in Dubai next month, world leaders still say “a 1.5-degree limit is achievable.” Lamboll said limiting warming to 1.5 degrees is technically possible, but politically difficult and unlikely.
“We have reached a stage where the carbon budget of 1.5C is so small that it is almost meaningless,” said Glen Peters, a climate scientist at CICERO, the Norwegian Climate Institute, who was not involved in the study. “If your face is going to hit the wall at 160 miles per hour, it doesn’t matter if your nose is 1 millimeter or 2 millimeters from the wall… At 100 miles per hour, we’re still going in the wrong direction. .”
Piers Forster, a climate scientist at the University of Leeds who was not part of Lamboll’s team, said people “shouldn’t worry, they should take action”. Taking action as soon as possible “could halve the rate of warming this decade.”
Source: Port Altele
