Human-Caused Climate Change Added 26 Days of Extreme Heat in Past 12 Months: Report

An estimated 6.3 billion people – about 78% of the global population – experienced at least 31 days of atypical warmth, which anthropogenic climate change made at least two times more likely to occur., the study found.

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Human-caused climate change is boosting extreme heat around the world, affecting billions of people and threatening food and water security, a new report has found.

According to a new joint analysis, carried out by Climate Central, Red Cross Red Crescent Climate Centre, and World Weather Attribution (WWA) and published Tuesday, 76 extreme heatwaves occurred between May 15, 2023 and May 15, 2024 across 90 countries. These included regions in the Global South, from the Sahel and Horn of Africa to Thailand, Myanmar, Vietnam, and the Philippines in Southeast Asia and Argentina, Brazil, Paraguay, and Bolivia in South America.

An estimated 6.3 billion people – about 78% of the global population – experienced at least 31 days of atypical warmth, which anthropogenic climate change made at least two times more likely to occur. The report classifies extreme heat days as days when the temperature exceeds 90% of the daily temperature recorded in a given place between 1991 and 2020.

2023 was the hottest year on record, supercharged by the El Niño weather pattern, which pushed temperatures off the charts around the world. Despite it gradually weakening, global temperatures have continued to rise this year, with April becoming the latest and 11th consecutive month to break records.

In the past 12 months, climate change added an average of 26 extreme heat days that would have otherwise not happened, the study found. However, in some countries, the number of excess heat days was exponentially higher. Suriname in South America saw an excess 158 extreme heat days; Ecuador 170, El Salvador 148; Guyana 141, and Panama 137.

Heatwaves are spreading rapidly across the world, affecting billions of people, with an increasing number of studies pointing at climate change as a driving factor. According to the Intergovernmental Panel on Climate Change (IPCC), with further global warming, we can expect an increase in the intensity, frequency and duration of heatwaves. Extreme heat impacts human health – particularly affecting vulnerable categories including the elderly and infirm, pregnant women, infants, outdoor workers, and athletes.

Stress on human bodies caused by heat prevents normal daily activities and our ability to cool down properly. Areas that generally have more humidity can also put lives at risk. Sweat helps our bodies cool off, but humidity changes the way sweat evaporates from the body. Not being able to cool down puts people’s health at risk, and can lead to increased cardiovascular and respiratory complications, dehydration, heatstroke, higher blood pressure, and sleep deprivation.

An April 2024 assessment by Copernicus Climate Change Service (C3S) and the World Meteorological Organization (WMO) found that heat-related mortality in Europe, which is warming twice as fast as any other continent, has increased by around 30% in the past two decades, while heat-related deaths are estimated to have increased in 94% of the European regions monitored.

Excess heat also compromises water and food resources and threatens both terrestrial and marine ecosystems. Recent marine heatwaves and near-record ocean temperatures.

The relentless rise of ocean temperatures has taken a toll on coral reefs around the world, leading to the fourth global coral bleaching event in history, already the second this decade. These important ecosystems support at least 25% of marine species; they are integral to sustaining Earth’s vast and interconnected web of marine biodiversity and provide ecosystem services valued up to $9.9 trillion annually. 

“Flooding and hurricanes may capture the headlines, but the impacts of extreme heat are equally deadly,” said Jagan Chapagain, Secretary-General of the International Federation of Red Cross and Red Crescent Societies (IFRC).

“We need to focus attention on climate change’s silent killer. The IFRC is making heat – and urban action to reduce its impacts – a priority and remains committed to working with communities that are at risk of extreme heat through our global network of National Societies.”

So far, the world has warmed by 1.2C compared to pre-industrial times, though data suggests that 20-40% of the global human population live in regions that, by the decade 2006–2015, had already experienced warming of more than 1.5C in at least one season. According to the Intergovernmental Panel on Climate Change (IPCC), every 0.5C (0.9F) of global warming will cause discernible increases in the frequency and severity of heat extremes, heavy rainfall events, and regional droughts.

The burning of coal, natural gas, and oil for electricity and heat is the single-largest source of global greenhouse gas (GHG) emissions, the primary drivers of global warming by trapping heat in the atmosphere and raising Earth’s surface temperature. Global fossil fuel consumption has more than doubled in the last 50 years, as countries around the world aim to improve their standards of living and economic output. In 2023, all three of the most potent GHGs – carbon dioxide (CO2), methane, and nitrous oxide – reached record highs.

The International Energy Agency (IEA) has urged countries to halt new gas and oil field projects, arguing that this is the only way to keep the 1.5C-compatible net-zero emissions scenario alive.

Featured image: Kyle Lam/hongkongfp.com