Global
temperatures could break heat record in next five years
Data also
shows small but ‘shocking’ likelihood of year 2C hotter than preindustrial era
before 2030
Jonathan
Watts
Wed 28 May
2025 05.00 BST
There is an
80% chance that global temperatures will break at least one annual heat record
in the next five years, raising the risk of extreme droughts, floods and forest
fires, a new report by the World Meteorological Organization (WMO) has shown.
For the
first time, the data also indicated a small likelihood that before 2030, the
world could experience a year that is 2C hotter than the preindustrial era, a
possibility scientists described as “shocking”.
Coming after
the hottest 10 years ever measured, the latest medium-term global climate
update highlights the growing threat to human health, national economies and
natural landscapes unless people stop burning oil, gas, coal and trees.
The update,
which synthesises short-term weather observations and long-term climate
projections, said there was a 70% chance that five-year average warming for
2025-2029 will be more than 1.5C above preindustrial levels.
This would
put the world perilously close to breaking the most ambitious target of the
Paris Agreement, an international climate change treaty, though that goal is
based on an average over 20 years.
It also
reported an 86% likelihood that 1.5C would be passed in at least one of the
next five years, up from 40% in the 2020 report.
In 2024, the
1.5C threshold was breached on an annual basis for the first time – an outcome
that was considered implausible in any of the five-year predictions before
2014. Last year was the hottest in the 175-year observational record.
Underscoring
how rapidly the world is warming, even 2C is now appearing as a statistical
possibility in the latest update, which is compiled by 220 ensemble members
from models contributed by 15 different institutes, including the UK’s Met
Office, Barcelona Supercomputing Centre, the Canadian Centre for Climate
Modelling and Analysis, and Deutscher Wetterdienst.
The
likelihood of 2C before 2030 is tiny – about 1% – and would require a
convergence of multiple warming factors, such as a strong El Niño and positive
Arctic Oscillation, but it was previously considered impossible in a five-year
timeframe.
“It is
shocking that 2C is plausible,” said Adam Scaife of the Met Office, which
played a leading role in compiling the data. “It has come out as only 1% in the
next five years but the probability will increase as the climate warms.”
The impacts
will not fall equally. Arctic winters are predicted to warm 3.5 times faster
than the global average, partly because sea ice is melting, which means snow
falls directly into the ocean rather than forming a layer on the surface to
reflect the sun’s heat back into space. The Amazon rainforest is predicted to
suffer more droughts while south Asia, the Sahel and northern Europe, including
the UK, will see more rain.
The Met
Office’s Leon Hermanson, who led the production of the report, said 2025 is
likely to be one of the three warmest years on record.
Chris
Hewitt, director of climate services at the WMO, described a “worrying picture”
for heatwaves and human health. However, he said it was still not too late to
limit warming if fossil fuel emissions are cut.
“We must
take climate action,” he said. “1.5C is not inevitable.”
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