The year 2026 could finish as the hottest on record as an exceptionally strong El Nino, a periodic event that involves warming currents in the Pacific Ocean, adds to human-caused global warming, while the climate pattern is expected to exert an even greater influence on temperatures and extreme weather in 2027, the World Meteorological Organization said.
The global average surface temperature from January to September was about 1.47 C above the 1850-1900 pre-industrial average, according to the WMO State of the Climate Update 2026, released on the opening day of the annual United Nations climate change conference, COP31, in Antalya, Turkiye. El Nino, which has intensified since August, is likely to lift the full-year figure further.
Officially known as the 31st session of the Conference of the Parties to the UN Framework Convention on Climate Change, COP31 will run through Nov 20.
WMO Secretary-General Celeste Saulo said the past 12 years were the warmest on record, with 2023 to 2026 ranking as the four hottest years. The current El Nino is forecast to remain into early 2027 and may reach nearly four times the WMO threshold for declaring such an event between November and January.
El Nino is already affecting heat, rainfall, agriculture and health in 2026. It typically raises annual global mean temperatures by about 0.1 C to 0.2 C, according to the report. But its greatest effect is generally felt in the year after it develops, raising the prospect of another record-breaking year in 2027, Saulo said.
The report said ocean heat is heading for a 10th consecutive annual record, while global mean sea level has reached a new high. Hundreds of millions of people have endured dangerous heat this year, including an estimated 146.5 million in India during an April heatwave. European heatwaves, drought and wildfires caused more than 30,000 excess deaths, preliminary estimates showed.
UN Climate Change Executive Secretary Simon Stiell said the super El Nino was "turbocharging climate impacts" and turning the climate crisis into a global health crisis. He called for faster electrification and cleaner energy to reduce planet-warming pollution and protect households and health systems.
Alan Dangour, director of climate and health at Wellcome, a global charitable foundation, said fossil-fuel-related air pollution and extreme heat were estimated to kill more than 3 million people annually. He urged governments and businesses to put health, especially the protection of children, pregnant women, outdoor workers and older people, at the center of climate action.
The WMO said sustained observations and early warnings were increasingly vital. The number of countries reporting multi-hazard early warning systems rose from 56 in 2015 to 136 in 2025, but officials stressed that greater financing, faster emissions cuts and stronger protection for vulnerable communities remain essential.
