Without climate change, these catastrophes would not have happened.

Droughts, storms, heat waves and wildfires: extreme weather around the world is becoming more intense and frequent. The cost is enormous and growing, with lives lost, homes destroyed, livelihoods stolen and economies crippled.

The extreme events are happening in the context of a very rapid warming of the climate. The world is already 1.2 degrees Celsius warmer than in pre-industrial times, and the next five years are predicted to be the warmest on record.

People often want to know if an extreme weather event happened because of climate change, said Friederike Otto, a climate scientist and co-leader of the World Weather Attribution initiative.

But it’s not a simple question. “You can’t answer with yes or no,” she said at a news conference last week. It’s because climate change alters the likelihood and intensity of extreme events, she said.

Otto and other scientists are using a scientific technique to transform our understanding of how this dynamic plays out. And more often than not, they’re finding the clear fingerprints of climate change in extreme events.

Called “attribution,” the method involves analyzing real-world observations as well as climate models to establish whether a given extreme event could have happened in a world without global warming.

While attribution studies are not done for every extreme weather event, they do help bring home the realities of the direct and immediate damage the climate crisis is doing to people’s lives, which scientists say will only get worse if the world continue to pump out the pollution that warms the planet.

“We’re always going to have extreme weather, but if we keep going in this direction, we’re going to have a lot of extreme weather,” said Ted Scambos, a glaciologist at the University of Colorado-Boulder.

From intense heat and record drought to severe storms fueled by air and warmer oceans, here are 10 disasters that show the devastating impacts of the man-made climate crisis.

“Impossible” Events

In some cases, the impacts of climate change are so clear and overwhelming that scientists conclude that extreme weather events would have been virtually impossible without global warming. These six events fall into the category:

Heat wave in Siberia, 2020

In 2020, a prolonged and unprecedented heat wave hit one of the coldest places on Earth, triggering widespread wildfires. Temperatures in the small Siberian town of Verkhoyansk reached 38 degrees Celsius, the hottest ever recorded in the Arctic.

The unrelenting heat, which lasted from January to June and raised temperatures 5 degrees Celsius above average, would have been “almost impossible” in a climate not warmed by carbon pollution, according to the Attribution Initiative’s rapid assignment study.

The heat wave was made at least 600 times more likely by the climate crisis, the scientists concluded, finding that this prolonged Arctic heat would happen less than once every 80,000 years without human-induced climate change.

Andrew Ciavarella, lead author of the research and Senior Detection and Attribution Scientist at the UK Met Office, called the findings “truly impressive”.

Pacific Northwest Heat Wave, 2021

The end of June 2021 was an unforgettable one for parts of the Pacific Northwest. A historic heat wave killed hundreds of people, sparked devastating fires and exacerbated an already unrelenting drought in parts of the region.

Oregon, Washington and Canada’s western provinces, including British Columbia, had record temperatures, which reached 49.6 degrees Celsius in the Canadian village of Lytton, which subsequently burned in a wildfire.

According to an analysis by more than 20 scientists from the attribution initiative, the June heatwave “would have been virtually impossible” without the influence of man-made climate change.

“Our results provide a strong wake-up call: our rapidly warming climate is taking us into uncharted territory that has significant consequences for health, well-being and livelihoods,” the authors wrote.

Drought in the Northern Hemisphere, 2022

From North America to Europe to China, vast areas of the Northern Hemisphere experienced extreme drought in the summer of 2022, depleting water resources, ruining crops and setting the landscape for dangerous wildfires.

Attribution initiative scientists concluded that climate change made these dry conditions at least 20 times more likely. The high temperatures would have been “impossible” without climate change, according to the analysis.

The western US has seen water levels drop, worsening the drought and leaving farmland fallow. And China and Europe have seen thousands of heat-related deaths. Heat and drought in Europe have killed at least 15,000 people, according to the World Health Organization.

“The northern hemisphere summer of 2022 is a good example of how extreme events caused by climate change can also occur over large regions over longer time periods,” said Otto.

Drought in the Horn of Africa, 2020-2023

A three-year drought in the Horn of Africa, one of the world’s most impoverished regions, has caused crops to wither, water to disappear and livestock to starve in large parts of Kenya, Somalia and Ethiopia.

The drought, which is the worst in 40 years, has had a catastrophic human impact, killing tens of thousands of people and leaving more than 20 million acutely food insecure.

That wouldn’t have happened without climate change, which made it at least 100 times more likely, according to a rapid attribution analysis.

“Almost half of the country’s population is affected, more than 3 million people are displaced,” said Mamunur Rahman Malik, Somali representative to the World Health Organization. “The country continues to pay the price of global warming and climate change,” he added.

Drought in the Mediterranean, 2023

In April, a severe heat wave with much more late-summer temperatures swept through Spain, Portugal, Morocco and Algeria, exacerbating a severe drought that had already left crops dry and drained critical water resources.

Human-caused global warming has made the western Mediterranean heat wave at least 100 times more likely. Scientists said the heat, which exceeded 40.6 degrees Celsius in parts of Morocco, would have been “almost impossible without climate change”.

Before Earth warmed up, such an intense event would only be expected once in 40,000 years, scientists found.

Extreme heat in South Asia, 2023

Large parts of South Asia faced a brutal heat wave in April. Countries such as Vietnam, Myanmar, Laos, India and Bangladesh set new all-time temperature records.

In Thailand, temperatures reached 45 degrees Celsius for the first time, but the humidity caused temperatures to be much higher.

In Thailand and Laos, the wet heat wave would have been “impossible” without the climate crisis, according to scientists at the Attribution Initiative. While heat in India and Bangladesh has become at least 30 times more likely due to human-caused climate change, the same analysis found.

… and those made much more likely or more severe by climate change

For other extreme weather events, the effect of the human-caused climate crisis is to make them more likely or more severe:

Australia’s Black Summer Fires, 2019-2020

Australia experienced months of blood-red skies and thick gray smoke in the summer of 2019-2020, as devastating bushfires swept through many parts of the country. Vivid images emerged of firefighters rescuing koalas and people wetting the burned hands of kangaroos.

The fires, which raged across an estimated 50 million acres, were associated with more than 400 deaths, with thousands admitted to hospital due to conditions related to smoke from wildfires. Nearly three billion animals have been killed or displaced by wildfires.

Human-caused climate change has made the conditions that led to severe wildfires at least 30% more likely, according to an analysis by the World Weather Attribution.

Drought in the western US, 2020-2023

The western United States has faced its worst drought in centuries in recent years, fueling devastating wildfires and causing water shortages.

In California, the summer of 2021 saw the most extreme drought on record in the state. A hydroelectric plant on Lake Oroville, the state’s second-largest reservoir, was forced to close due to low water levels for the first time since it opened in 1967.

Meanwhile, two of the nation’s largest reservoirs, Lake Mead and Lake Powell, have fallen so low that government officials have imposed unprecedented water cuts in Nevada and Arizona, as well as Mexico.

A study in the journal Nature Climate Change found that the period from 2000 to 2021 was the driest the West has been in 1,200 years, noting that human-caused climate change has worsened the mega-drought by 72%.

Hurricane Ian, 2022

When Hurricane Ian swept across the Caribbean and made landfall in Florida in 2022, it left a trail of destruction, killing more than 100 people and causing an estimated $65 billion in damage. Extreme rainfall caused massive damage and scientists say it was intensified by global warming.

The hurricane was at least 10% wetter because of climate change, according to an analysis by scientists at Stony Brook University and Lawrence Berkeley National Laboratory.

Pakistan floods, 2022

Massive flooding caused by record monsoon rains killed nearly 1,500 people during the summer of 2022, with millions more affected by clean water and food shortages.

The floods left a third of Pakistan under water. The country received more than three times the normal rainfall in August, making it the wettest August since 1961. UN Secretary-General António Guterres said the Pakistani people faced “a monsoon on steroids”.

Climate change has made rainfall in the hard-hit provinces of Sindh and Balochistan 50% more intense than it would have been had the climate not warmed by 1.2 degrees Celsius, according to a study by the Attribution Initiative.