Global temperatures are likely to rise to record levels over the next five years, driven by human-caused warming and a climate pattern known as El Niño, forecasters at the World Meteorological Organization said on Wednesday.
The record for the planet’s hottest year was set in 2016. Forecasters said there’s a 98% chance that at least one of the next five years will surpass that, while the average from 2023 to 27 will almost certainly be the warmest in the world. five-year period ever recorded.
“This will have far-reaching implications for health, food security, water management and the environment,” said Petteri Taalas, secretary-general of the meteorological service. “We need to prepare.”
Why it matters: Each part of the degree brings new risks.
Scientists say small increases in warming can exacerbate the risk of heat waves, wildfires, droughts and other disasters. High global temperatures in 2021 Help fuel a heat wave In the Pacific Northwest it broke local records and killed hundreds of people.
El Niño conditions can cause further disruption by altering global precipitation patterns. The meteorological organization said it expects increased summer precipitation over the next five years in places such as northern Europe and the Sahel in sub-Saharan Africa, and decreased precipitation in the Amazon and parts of Australia.
The organization stated that there is also a two-thirds chance that one of the next five years will be 1.5 degrees Celsius, or 2.7 degrees Fahrenheit, warmer than the 19th-century average.
This does not mean that the world will have formally breached the Paris Agreement’s ambitious target of reducing global warming to 1.5°C. When scientists talk about this temperature target, they generally mean a longer-term average over, say, two decades in order to eradicate the effect of natural variation.
Many world leaders have insisted on a 1.5 degree limit to keep climate change risks at tolerable levels. But states are long overdue in making Huge changes Essential to achieving this goal, such as significantly reducing fossil fuel emissions, scientists now believe the world is likely to exceed this limit in the early 2030s.
Background: La Niña, a cooling effect, is on its way out.
Average global temperatures have already risen by about 1.1°C since the 19th century, largely because humans continue to burn fossil fuels and pump greenhouse gases like carbon dioxide into the atmosphere.
But while this general upward trend is clear, global temperatures can bounce up and down slightly from year to year due to natural variability. For example, a periodic phenomenon in the Pacific Ocean, and El Niño – Southern OscillationIt causes fluctuations from year to year by transporting heat in and out of the deeper ocean layers. Earth’s surface temperatures tend to be somewhat cooler during La Niña years and somewhat hotter during El Niño years.
The last hot year, 2016, was an El Niño year. By contrast, La Niña conditions have dominated most of the past three years: While it was unusually warm, were still just below 2016 levels. Now, scientists expect El Niño conditions to return later this summer. When combined with steadily rising levels of greenhouse gases in the atmosphere, this is likely to accelerate temperatures to new highs.