How heat fueled extreme weather across the world in 2023

By Gloria Dickie, Travis Hartman and Clare Trainor

DUBAI (Reuters) – One after another, records have fallen in 2023 alongside skyrocketing temperatures.

Deadly floods, heatwaves and storms have unfolded against the backdrop of what climate scientists say is set to be the world’s hottest year on record, with observations stretching back to the 1800s.

The world, on average, has seen about 1.46 degrees Celsius (2.63 degrees Fahrenheit) of warming above pre-industrial temperatures this year, with global greenhouse gas emissions hitting new highs.

Every new benchmark brings crippling economic losses and untold human suffering to communities across the world.

This year’s added warming has been like pouring gasoline on a fire. Extremes became more extreme. Warmer ocean waters fed stronger storms. Heatwaves persisted for weeks instead of days. And wildfires, feeding on dry forests and high temperatures, burned out of control.

An El Nino climate pattern, which emerged in the Eastern Pacific in June, is making things worse, scientists said. It’s boosting the warming caused by climate change, unleashing more catastrophic extremes.

As world leaders seek to bring an end to fossil fuels at the United Nations climate summit COP28 in Dubai, scientists say the record-breaking extremes of 2023 serve as a sobering warning of what’s to come if society doesn’t curtail its use of coal, oil and gas.


In October, Otis began swirling off Mexico’s southern Pacific coast. In a matter of hours, it went from a fairly weak tropical storm to a major hurricane before barrelling into the city of Acapulco, leaving dozens dead. It was the first eastern Pacific hurricane to remain at Category 5 after making landfall.

Scientists blamed much warmer than usual ocean temperatures in October, with sea surface temperatures off the eastern coast of Mexico at around 31C (88F) as Otis gathered strength.

Hot water at greater depths, scientists said, may also have given Otis an extra boost.

Research released just days before Otis hit hinted at a worrying trend in other oceans. The study, published in the journal Scientific Reports, found Atlantic hurricanes are now far more likely to gain steam in a short window of time than they were decades ago.

Still, it will take some time for scientists to figure out exactly how climate change supercharged Otis.


When the remnants of Typhoon Doksuri hit northeastern China midway through the summer, it deluged cities from Beijing to Tianjin. Flood waters submerged streets and tore through buildings, displacing more than 1 million people from their homes.

The typhoon — the same weather phenomenon as a cyclone or hurricane — was part of a one-two punch, emerging after a period of record-breaking heat on land in northern China.

Scientists say it’s not surprising to have seen record-breaking rainfall following such heatwaves. After all, warmer air can hold more moisture. When clouds burst, they send a torrent of water rushing down.


Millions sweltered under stifling temperatures with the arrival of summer in the Northern Hemisphere — and the world’s warmest month ever recorded in July. Large swathes of North America, Europe and China saw blistering temperatures that triggered public health warnings, briefly shuttered tourist sites and helped to fuel deadly wildfires.

A remote township in China’s arid northwest hit 52.2C (126F), setting a new record for the country. Beijing suffered through 27 consecutive days of temperatures above 35C (95F), leading to a temporary ban on outdoor work in the Chinese capital.

Halfway across the world, the United States also sizzled. Phoenix, Arizona, saw a record 31-day streak of temperatures of 43C (110F) or greater from June 30 to July 30.

And in parts of Spain, Greece and Italy, temperatures climbed upwards of 45C (113F).

Climate change is making heatwaves even worse.

The heatwaves that unfolded across three continents this summer would have been extremely rare without climate change, according to the World Weather Attribution (WWA) group, a team of international scientists who tease out the role played by climate change in extreme events.

In China, the heatwave would have been a 1-in-250 year event, they said.

In Phoenix, the summer heat of 2023 would have been virtually impossible without human-caused climate change.


As the world registered its warmest June, July and August on record, fires broke out across the globe.

In early June, smoke from eastern Canadian wildfires blanketed cities across North America, creating hellish orange skies and triggering dangerous air quality alerts for the region. Canada went on to experience its worst wildfire season on record.

More than 45 million acres (18.4 million hectares) of forest have burned across the country as of November 2023, or about 5% of Canadian forests, impacting woodlands from Alberta to Quebec to Nova Scotia. The fires release more than 400 million metric tons of carbon, nearly triple the previous record set in 2014 of 138 million metric tons.

Scientists said climate change made the fires in Eastern Canada from May through July at least twice as likely.

Apocalyptic fires also blazed through northeastern Greece following weeks of high heat which saw the Acropolis briefly close to tourists. The fires were the worst on European soil in decades, according to the EU’s Copernicus Climate Change Service, burning an area larger than New York City and costing the country some 1.66 billion euros ($1.8 billion).


The warm temperatures experienced so far throughout the year show no signs of letting up.

November once again was the warmest November ever recorded. And on Nov. 17 and 18, the Earth’s global average surface temperature was more than 2C (3.6F) higher than pre-industrial levels — the first time scientists have ever recorded such a reading.

Brazil — currently in the Southern Hemisphere’s summer — recorded its highest temperature ever as the southeastern town of Aracuai simmered at 44.8C (112.6F) on Nov. 19 as the full weight of El Nino bore down.

With El Nino set to reach its full strength in the Northern Hemisphere winter, more extreme weather events are likely to be unleashed around the world in 2024.

(Reporting by Gloria Dickie in Dubai, Travis Hartman in New York and Clare Trainor in Los Angeles; Editing by Julia Wolfe, Katy Dagle and Lisa Shumaker)