Is 2023 going to be the hottest year on record?

This article was originally published in May 2023, then updated in July 2023, October 2023 and again in November 2023.

The UK, Vietnam, Poland, Spain, China, Latvia, Myanmar, Portugal, Belarus, the Netherlands, Thailand … these are just some of the countries where temperature records have been broken this year.

And the global temperature records just keep on coming.

Earth has this year experienced its hottest October, September, August and July on record. Temperatures in October were 0.85°C above the 1991-2020 average for the month, and 0.4°C higher than the previous warmest October, which came in 2019, according to the Copernicus Climate Change Service.

This came just a month after one climate scientist described September temperatures as "gobsmackingly bananas". Temperatures that month were 0.5°C above the previous September record.

As for August, that rewrote the 174-year history of the National Oceanic and Atmospheric Administration's (NOAA) global climate record. The heat wave that month led to record temperatures in four continents – Africa, Asia, North America and South America.

And before this, 6 July was the planet's hottest day ever, with the global average temperature reaching 17.2°C. This came after three days of temperature records being broken – and after the warmest June since records began.

Meanwhile, the southern hemisphere experienced its warmest April on record and its warmest month ever, according to the US National Oceanic and Atmospheric Information (NOAA). The average temperature during the month was 0.9°C above the 20th-century average.

And globally, 2023 saw the second-warmest March on record, according to NASA, NOAA, the Japanese Meteorological Agency and the EU’s Copernicus Climate Change Service (C3S).

“It was much warmer than average over a vast swathe of land covering North Africa, south-western Russia and most of Asia, where many new high-temperature records for March were set,” says C3S. “Above-average temperatures also occurred over north-eastern North America, Argentina and neighbouring countries, as well as across a large part of Australia and coastal Antarctica.”

“We can say with near certainty that 2023 will be the warmest year on record, and is currently 1.43°C above the pre-industrial average,” said the Copernicus Climate Change Service's Deputy Director, Samantha Burgess, following the news of the October temperature records.

Climate change is playing a major part in this shift. The World Meteorological Organization (WMO) has also said – for the first time ever – that global temperatures are more likely than not to move more than 1.5­°C above pre-industrial levels in the next five years.

Another major factor is the anticipated return of the El Niño weather phenomenon. The WMO says this combination is set to push global temperatures to a new record in the next five years, while climate scientists from a range of other organizations say that this could happen as soon as this year or 2024.

El Niño – which means 'little boy' in Spanish – is the term for when warmer waters cause the Pacific jet stream to move south of its neutral position. This leads to areas in the northern United States and Canada becoming warmer than usual, the NOAA says.

"El Niño is normally associated with record-breaking temperatures at the global level,” C3S Director Carlo Buontempo explains. “Whether this will happen in 2023 or 2024 is not yet known, but it is, I think, more likely than not."

The world's hottest year on record is 2016, when there was a strong El Niño. And the world's eight hottest years on record have all come in the past eight years – a trend that has coincided with rising CO2 emissions, as the charts below show.

This year looks likely to bring together an El Niño and rising CO2 emissions. Global energy-related CO2 emissions rose by 0.9% to a record of over 36.8 gigatonnes last year, the International Energy Agency says. And the world’s two largest economies show no sign of cutting back – US energy-related carbon emissions are predicted to rise this year, and China’s carbon emissions hit a new high in the first quarter of 2023.

“Depending on how quickly the coming El Niño develops and how strong it becomes, by the end of December 2023, temperatures could easily surpass all other years we’ve seen so far,” says meteorologist Scott Sutherland. “Based on the pattern that has played out in the past, especially in 2015 and 2016, next year will likely be even hotter.”

The rapid increases in temperatures during March were partly due to rising sea surface temperatures in the equatorial Pacific Ocean, Sutherland says.

And in April, global ocean temperatures went on to set a new record for the month, sitting 0.86°C above the long-term average, the NOAA points out. “This marked the second-highest monthly ocean temperature for any month on record, just 0.01°C shy of the record-warm ocean temperatures set in January 2016,” it adds.

Other temperature records already broken this year include the UK experiencing its hottest-ever June, Vietnam hitting just over 44.1°C, Myanmar touching 43.8°C – its highest for a decade – and Spain and Portugal breaching April records in certain cities. Numerous European countries also broke January temperature records this year.

And in mid-May, temperatures in the Western US and Canada soared above levels normally recorded in late July, triggering wildfires. A “heat dome” weather system is hitting the area – when the atmosphere forms a lid trapping hot ocean air – revealing “clear fingerprints of climate change” according to Climate Central, an independent group of scientists.

Extreme weather is ranked as the second-biggest risk facing the world in the next two years and the third-biggest risk in the next 10 years, according to the World Economic Forum Global Risks Report 2023. The biggest risk in the next 10 years is seen as a failure to mitigate climate change.

“Heatwaves and droughts are already causing mass mortality events (a single hot day in 2014 killed more than 45,000 flying foxes in Australia),” the report says. “As floods, heatwaves, droughts and other extreme weather events become more severe and frequent, a wider set of populations will be affected.”

The World Economic Forum has a number of initiatives supporting the industry action needed to accelerate the overhaul of national energy systems and help limit global warming to less than 1.5°C above pre-industrial levels. This includes the Alliance of CEO Climate Leaders, Industrial Clusters: The Net-Zero Challenge and the Low-Carbon Emitting Technologies Initiative.