An unprecedented rise in global temperature is likely to see the 1.5 degrees Celsius (2.6 degrees Fahrenheit) threshold of the Paris Agreement crossed at some point in the next five years, according to a United Nations report ( UN).
The UN’s World Meteorological Organization (WMO) issued a stark warning in its latest annual assessment. According to the WMO, there is a 66% chance that the annual average global surface temperatures will temporarily cross the threshold of a 1.5°C rise above pre-industrial levels. It would be the first time in human history that such an increase would be recorded.
Scientists have warned that crossing the 1.5C threshold dramatically increases the risks of encountering tipping points that could trigger irreversible climate breakdown – such as the collapse of the Greenland and West Antarctic ice sheets; extreme heat waves; severe droughts; water stress; And extreme weather conditions over large parts of the globe.
Related: A significant El Niño event is almost guaranteed this year, experts warn. And it could be a big one.
Around 200 countries have pledged to limit global temperature rise to 1.5°C or less in the Paris Agreement 2015. Now, even temporarily, this limit could be exceeded for the first time.
“An El Niño warming is expected to develop in the coming months, and this will combine with climate change to push global temperatures into uncharted territory,” Petteri Taalasthe Secretary General of WMO, shelp in a declaration. “This will have profound implications for health, food security, water management and the environment. We must be prepared.
El Niño occurs when the trade winds, which typically push warm water west across the Pacific Ocean from South America to Asia, weaken, keeping more of the water hot in place. This strongly affects weather patterns around the world, making South America wetter and causing drought (and sometimes famine) in regions such as Australia, Indonesia, northern China and northern -eastern Brazil.
In the United States, El Niño tends to make northern regions hotter and drier and southern regions wetter, and because it causes warmer water to spread farther and stay near the surface from the ocean, it also warms the atmosphere around the world.
The WMO’s latest report covers the years 2023 to 2027. It says there’s a 98% chance that one of the next five years will be the hottest on record – surpassing Record temperature rise of 2.3 F (1.28 C) in 2016.
The risks of higher temperature variations are also increasing: the chances of crossing the temperature threshold of 1.5 C were close to zero in 2015; it rose to 48% in 2022; and is now 66% a year later.
The researchers said much of this warming would be unevenly distributed. THE Arcticfor example, will see temperatures fluctuate three times more than in the rest of the world, accelerating the melting which could have serious repercussions on weather systems such as the Jet Stream and the North Atlantic Current – systems crucial for the temperature regulation in the Northern Hemisphere.
Precipitation, meanwhile, is expected to decrease in Central America, Australia, Indonesia and the Amazon. Deforestation, climate change and fires have caused the gigantic rainforest to lose some of its resilience since the 2000s, leading scientists to fear it may be crossing a tipping point that could turn it into savannah.
The report notes that there is only a 32% chance that the five-year average will exceed the 1.5°C threshold, but this average has nevertheless risen dramatically since 2015, when it was near zero. .
“This report does not mean we will permanently exceed the 1.5C level specified in the Paris Agreement, which refers to long-term warming over many years,” Taalas said. “However, the WMO is sounding the alarm that we will temporarily breach the 1.5C level with increasing frequency.”