UN Secretary-General António Guterres declared that the world is on a “highway to climate hell with our foot still on the accelerator” as the United Nations COP27 climate summit got underway in Egypt. We must severely restrict greenhouse gas emissions if we want to prevent global temperatures from reaching 1.5 degrees Celsius above preindustrial levels by 2100. Hard.
In fact, we’d essentially need to stop the rogue vehicle dead in its tracks.
Although the climate commitments made by countries at the COP26 conference last year felt like a step in the right direction, there is little doubt that the average temperature rise on Earth will exceed the 1.5 degree mark in the coming decades — a scenario known as a “overshoot” — before possibly returning to the 1.5 degree range by the end of the century.
According to Gokul Iyer, a researcher at the Joint Global Change Research Institute and the study’s first author, “if countries can ramp up their 2030 ambition during the COP this year, then that might dramatically minimize both the duration and the degree of overshoot.”
Long considered a turning point in the fight against climate change, the 1.5 degree rise. Since the Paris Agreement was ratified at COP21 seven years ago, researchers have carefully examined the effects of this degree of warming over preindustrial levels on the Earth. Additionally, the models and simulations they’ve developed imply that there will probably be more extreme weather events once temperatures push past an increase of 1.5 degrees.
Countries presented more aggressive emissions reduction commitments (known as NDCs) at COP26 in November 2021 in an effort to slow global warming. Even if these commitments are fulfilled, according to research done by Iyer, Haewon McJeon, and colleagues last year, temperatures are still predicted to rise by around 1.8 degrees Celsius by the end of the century.
The Glasgow Climate Pact, formed at COP26, required countries to make ever-ambitious decarbonization commitments. The publication of the new study coincides with a crucial conversation taking place in Egypt’s enormous conference rooms for COP27.
We are looking at an overshoot era that could linger for decades and go well into 2100 if ambitions are not scaled up in the near future. There is a chance to cut the overshoot time to about half a century, though, if nations step up their commitments, as outlined in the Glasgow Climate Pact last year. That might have a significant effect on both human and environmental health.