The Next Five Years Will Almost Certainly Be the Warmest on Record, U.N. Says

Earth is likely to pass 1.5 degrees Celsius of warming over pre-industrial levels, a key climate threshold, by 2027, according to a new report

Man looks at a wildfire
Wildfire during Greece's 2021 heatwave, which experts have linked to climate change Angelos Tzortzinis / AFP via Getty Images

For the first time in human history, the Earth’s average temperature is more likely than not to cross a critical warming threshold during at least one of the next five years, per a new report released Wednesday by the World Meteorological Organization (WMO).

Scientists now predict the Earth has a 66 percent chance of hitting 1.5 degrees Celsius (2.7 degrees Fahrenheit) of warming over pre-industrial levels between now and 2027—and a 98 percent chance of the five-year period as a whole being the hottest on record.

1.5 degrees Celsius is a key climate threshold. In the Paris agreement of 2015, nations agreed to “pursue efforts” to cap long-term warming at that amount. Scientists warned of dire consequences if this is exceeded, including extreme storms, coral reef die-offs, melting ice, flooding, heat waves and drought.

“This report does not mean that we will permanently exceed the 1.5C specified in the Paris agreement, which refers to long-term warming over many years,” WMO Secretary-General Petteri Taalas says in a statement. “However, WMO is sounding the alarm that we will breach the 1.5C level on a temporary basis with increasing frequency.”

So far, nations have fallen short on their promises to limit greenhouse gas emissions from burning fossil fuels, which is driving climate change. This has put the world on track to reach about 3 degrees Celsius of warming this century. 

The past eight years were the hottest on record globally. In 2015, the likelihood of temporarily hitting the 1.5-degree threshold was close to zero, per the WMO. Between 2017 and 2021, that had risen to 10 percent, and by 2022, it was at almost 50 percent. This January, several countries in Europe smashed temperature records for the month. 

Now, Earth has just reached the end of a La Niña weather pattern—which lasted three years and has a cooling effect—and a warming El Niño event is on the way. As a result, researchers expect the planet will get even hotter. The current warmest year on record was 2016, and that came after a strong El Niño event. With the upcoming El Niño conditions, 2024 could become the warmest year yet, report Laura Paddison and Jessie Gretener for CNN

“Projections for the warmest year on record in the next five years spells further trouble for the health of people around the world,” Belle Workman, a climate researcher at the University of Melbourne in Australia, tells Paul McClure of New Atlas. “We know that climate change negatively impacts health in a variety of ways, including through the direct physical effects of heatwaves, such as heat stroke, and indirect effects of rising temperatures, such as contributing to food and water insecurity.”

While the window is rapidly closing to secure a “livable and sustainable future for all,” it’s not too late, per the latest Intergovernmental Panel on Climate Change report. Immediate, deep, rapid and sustained greenhouse gas emissions reductions are needed to slow down global warming, per the report. 

“Our world needs climate action on all fronts: everything, everywhere, all at once,” U.N. Secretary-General António Guterres said in a statement in March. “We have never been better equipped to solve the climate challenge—but we must move into warp speed climate action now. We don’t have a moment to lose.”

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