State of the Climate 2026: What WMO's COP31 Report Says

What does the State of the Climate 2026 report say?

The World Meteorological Organization (WMO) says 2026 will be one of the four warmest years on record, with record ocean heat and sea level and a very strong El Niño set to bring more heat and extreme weather well into 2027 ^[1][2]. The State of the Climate Update 2026 was released on 9 November 2026, the first day of the UN climate conference COP31 in Antalya, Türkiye ^[1][2].

WMO's five key messages are ^[1][2]:

• 2026 will be one of four warmest years on record;
• El Niño turns up the heat and multiplies risks;
• sea level and ocean heat are at record high levels;
• extreme weather has massive economic and human cost;
• forecasts and warnings, underpinned by sustained observations, are vital.

"El Niño and indeed the state of the global climate in 2026 gives new meaning to the phrase off the charts," said WMO Secretary-General Celeste Saulo ^[1]. The update uses data up to September where available, so WMO notes it does not reflect the most recent impacts of El Niño ^[1][2].

How warm is 2026 compared with other years?

January to September 2026 averaged about 1.47 °C above the 1850–1900 pre-industrial baseline, with an uncertainty of ±0.13 °C ^[1]. That is comparable to the full-year averages for 2025 (1.43 °C) and 2023 (1.46 °C), and below the 2024 record of 1.55 °C ^[1].

WMO bases the figure on nine internationally recognised datasets: Berkeley Earth, CMA-GMST, CMST, DCENT-I, ERA5, GISTEMP, HadCRUT5, JRA-3Q and NOAAGlobalTemp ^[1]. The past 12 years (2015–2026) are each among the warmest on record, and the past four, 2023 to 2026, are the top four ^[1][2].

The final 2026 number is likely to be higher than the nine-month average. La Niña cooled the start of the year, but El Niño reversed that, and WMO says El Niño typically adds around 0.1 °C to 0.2 °C to annual global temperatures ^[1]. Saulo said El Niño usually has its greatest impact in the year after it develops, "why we should therefore prepare for another record-breaking year in 2027" ^[5].

Separately, the Copernicus Climate Change Service reported that October 2026 was the warmest October on record, 1.75 °C above pre-industrial, and that 2026 is virtually certain to be the second calendar year above 1.5 °C, as summarised by the Royal Meteorological Society ^[4][6]. That is a single-month figure, so it is not directly comparable with WMO's January to September average from nine datasets.

Why is El Niño making 2026 so extreme?

Because it releases heat stored in an ocean that is already the warmest ever measured ^[1]. "El Niño doesn't add new heat to the planet. It releases heat from the ocean, which is the warmest ever measured. There is simply more heat available to release," Saulo said ^[1][3].

WMO says El Niño has been intensifying since August and is expected to be the strongest on record by December, continuing into early 2027 ^[1]. In her press conference statement, Saulo explained that WMO declares an El Niño when tropical Pacific sea surface temperatures are 0.5 °C above average, and that between November 2026 and January 2027 it may be nearly four times that level ^[5].

El Niño also tends to push greenhouse gas concentrations up, as WMO notes in the same report ^[1]. For a full explanation of this year's event and what it means for winter weather, see El Niño 2026: How Strong It Is and What It Means for Winter.

How high are greenhouse gases, ocean heat and sea level?

All three are at record levels, WMO says ^[1].

• Greenhouse gases: carbon dioxide reached about 426.8 parts per million in 2025, up 53% from around 278 ppm in 1750. Methane reached 1,948 parts per billion (up 167%) and nitrous oxide 339.1 ppb (up 26%). Stations such as Mauna Loa in Hawaii and Kennaook/Cape Grim in Australia show a continued rise in 2026 ^[1].
• Energy imbalance: the rate at which Earth accumulates heat reached its highest value since monitoring began in 1960 in 2025, and preliminary January–July 2026 values suggest another record ^[1].
• Ocean heat: the upper 2,000 metres held the most heat on record in 2025 and kept rising in 2026. The ocean absorbs about 90% of the excess heat ^[1].
• Sea level: global mean sea level hit a record high in 2026, with June, July and August the highest since satellite altimetry began in 1993 ^[1][2]. Saulo said this raises risks for 900 million people on low-lying coasts ^[5].

WMO says ocean warming is projected to continue for hundreds to thousands of years ^[1][3].

What is happening to glaciers and sea ice?

Glaciers lost more than 400 gigatons of ice in 2025, equal to about 1 mm of global sea-level rise, and both polar sea ice maximums in 2026 were among the lowest on record ^[1].

WMO says that annual glacier loss would have filled five Olympic swimming pools every second of the year, and 2025 was the fourth year in a row in which all 19 glaciated regions lost ice ^[1]. In 2026, Antarctic sea ice reached its third-lowest annual maximum in the satellite era since 1979, and the Arctic maximum was the lowest or second lowest ^[1].

Fresh water on land is also falling. Water stored in groundwater, soil, rivers, reservoirs, glaciers and snow has declined globally since 2014; in 2025, 42% of the assessed area had below-normal storage, against a long-term average of 25% ^[1].

Mountain hazards are a growing concern. WMO highlights a Himalayan glacier collapse and flash flood in late August 2026 that killed more than 1,300 people and badly hit Nepal's economy ^[1][3].

What did extreme weather cost in 2026?

Tens of thousands of lives and major economic damage, according to WMO's preliminary estimates ^[1][5].

• Europe: heatwaves, drought and wildfires led to more than 30,000 excess deaths, with national temperature records in at least eight countries ^[1]. UN News reports about 16,000 excess deaths during the 22–28 June heatwave alone ^[3].
• India: an estimated 146.5 million people were exposed to extreme heat in an April heatwave; UN News says temperatures hit 47 °C ^[1][3].
• Nepal: more than 1,300 deaths from the August glacier collapse and flash flood ^[1].
• Elsewhere: tropical cyclones caused deaths in many countries, and Saulo pointed to floods in parts of South America and Africa and drought in Asia, the Pacific and Central America as COP31 opened ^[1][5].

Health: WMO says the World Health Organization has, for the first time, classified the anticipated health impacts of El Niño as a health emergency, citing heat illness, smoke, malnutrition and water- and vector-borne diseases such as cholera, malaria and dengue ^[1][3]. This is not medical advice; follow your national health authority's heat and disease guidance.

What happens next after the COP31 report?

WMO will publish the final State of the Global Climate 2026 report in March 2027 ^[1], and Saulo is asking COP31 for decisions that deliver funding and for sustained observations from every part of the world ^[5].

There is some progress to report: the number of countries with multi-hazard early warning systems rose from 56 in 2015 to 136 in 2025 ^[1][5]. "We cannot afford to fly blind," Saulo said, urging sustained observations from every part of the world ^[5].

UN Secretary-General António Guterres said: "We have entered a new age of climate extremes. A supersized El Niño is colliding with a planet already superheated by manmade climate change," and called on leaders to cut emissions faster and deliver finance to vulnerable countries ^[1][3].

WMO has also launched a beta interactive platform to explore the data behind the report ^[1]. For another climate indicator released this season, see Ozone Hole 2026: How Big It Got and Is It Healing?