El Nino may push temperatures into 'uncharted territory'
The weather cycle may combine with human-induced climate change to cause a regular breach of the 1.5°C level.
The predicted El Nino weather cycle could push temperatures into “uncharted territory”, the World Meteorological Organization (WMO) has warned.
El Nino could combine with human-induced climate change to cause a regular breach of the 1.5°C level specified in the Paris Agreement, the group said.
The WMO added scientists were likely to record a global average temperature of more than 1.5C above pre-industrial levels over the next five years.
It said there was a 66% chance of this temperature being recorded at least once between now and 2027 - which would mark the first time in human history - and there was a 98% chance of the hottest year on record being broken during that time.
Read more: Warning of 'significant' El Nino event that could usher in record temperatures
WMO Secretary-General Professor Petteri Taalas said: “A warming El Niño is expected to develop in the coming months and this will combine with human-induced climate change to push global temperatures into uncharted territory."
He added: “This will have far-reaching repercussions for health, food security, water management and the environment. We need to be prepared.”
Prof Taalas said the report did not mean we would permanently exceed the 1.5°C level, which refers to long-term warming over many years.
Read more: UK weather: 'Large' El Niño is possible this summer, Met Office warns
But he said the WMO was sounding the alarm it would be breached on a temporary basis with increasing frequency.
The chance of temporarily exceeding 1.5°C has risen steadily since 2015, when it was close to zero, the WMO said.
It added for the years between 2017 and 2021, there was a 10% chance of exceedance.
But the WMO said there was only a 32% chance that the five-year mean will exceed the 1.5C threshold.
Watch: World 'more likely than not' to breach 1.5C soon
Typically, El Nino raises global temperatures the year after it develops, so scientists expect temperatures to rise in 2024.
The WMO said that its opposite – La Nina – has been cooling atmospheric temperatures for much of the last three years, but this has now ended.
Met Office research showed El Nino brought an increased risk of drought to South-East Asia, India, North-Eastern Australia and parts of the Amazon and southern Africa and increased risk of cold conditions to northern Europe in winter.
Dr Leon Hermanson, a Met Office expert scientist who led the WMO report, said: “Global mean temperatures are predicted to continue increasing, moving us away further and further away from the climate we are used to.”
In the Paris Agreement, the world’s nations committed to reducing their greenhouse gas emissions to contain the global temperature below 2C above preindustrial levels and to try for 1.5C before the end of the century.
The Intergovernmental Panel on Climate Change has said damage wrought on people and wildlife will increase with every increment of global warming.
It also said the world is currently on course to warm to well beyond 2C by the end of the century with the emissions reduction policies currently in place.