Published

1 month ago

February 24, 2026

Alice Rush

Rising temperatures across France since the mid-1970s is putting Tour de France competitors at “high risk”, according to new research.

The study, published in Scientific Reports, uses 50 years of climate data to calculate the potential heat stress that athletes have been exposed to across a dozen different locations during the world-famous cycling race.

The researchers find that both the severity and frequency of high-heat-stress events have increased across France over recent decades.

But, despite record-setting heatwaves in France, the heat-stress threshold for safe competition has rarely been breached in any particular city on the day the Tour passed through.

(This threshold was set out by cycling’s international governing body in 2024.)

However, the researchers add it is “only a question of time” until this occurs as average temperatures in France continue to rise.

The lead author of the study tells Carbon Brief that, while the race organisers have been fortunate to avoid major heat stress on race days so far, it will be “harder and harder to be lucky” as extreme heat becomes more common.

‘Iconic’

The Tour de France is one of the world’s most storied cycling races and the oldest of Europe’s three major multi-week cycling competitions, or Grand Tours.

Riders cover around 3,500 kilometres (km) of distance and gain up to nearly 55km of altitude over 21 stages, with only two or three rest days throughout the gruelling race.

The researchers selected the Tour de France because it is the “iconic bike race. It is the bike race of bike races,” says Dr Ivana Cvijanovic, a climate scientist at the French National Research Institute for Sustainable Development, who led the new work.

Heat has become a growing problem for the competition in recent years.

In 2022, Alexis Vuillermoz, a French competitor, collapsed at the finish line of the Tour’s ninth stage, leaving in an ambulance and subsequently pulling out of the race entirely.

Two years later, British cyclist Sir Mark Cavendish vomited on his bike during the first stage of the race after struggling with the 36C heat.

The Tour also makes a good case study because it is almost entirely held during the month of July and, while the route itself changes, there are many cities and stages that are repeated from year to year, Cvijanovic adds.

‘Have to be lucky’

The study focuses on the 50-year span between 1974 and 2023.

The researchers select six locations across the country that have commonly hosted the Tour, from the mountain pass of Col du Tourmalet, in the French Pyrenees, to the city of Paris – where the race finishes, along the Champs-Élysées.

These sites represent a broad range of climatic zones: Alpe d’ Huez, Bourdeaux, Col du Tourmalet, Nîmes, Paris and Toulouse.

For each location, they use meteorological reanalysis data from ERA5 and radiant temperature data from ERA5-HEAT to calculate the “wet-bulb globe temperature” (WBGT) for multiple times of day across the month of July each year.

WBGT is a heat-stress index that takes into account temperature, humidity, wind speed and direct sunlight.

Although there is “no exact scientific consensus” on the best heat-stress index to use, WBGT is “one of the rare indicators that has been originally developed based on the actual human response to heat”, Cvijanovic explains.

It is also the one that the International Cycling Union (UCI) – the world governing body for sport cycling – uses to assess risk. A WBGT of 28C or higher is classified as “high risk” by the group.

WBGT is the “gold standard” for assessing heat stress, says Dr Jessica Murfree, director of the ACCESS Research Laboratory and assistant professor at the University of North Carolina at Chapel Hill.

Murfree, who was not involved in the new study, adds that the researchers are “doing the right things by conducting their science in alignment with the business practices that are already happening”.

The researchers find that across the 50-year time period, WBGT has been increasing across the entire country – albeit, at different rates. In the north-west of the country, WBGT has increased at an average rate of 0.1C per decade, while in the southern and eastern parts of the country, it has increased by more than 0.5C per decade.

The maps below show the maximum July WBGT for each decade of the analysis (rows) and for hourly increments of the late afternoon (columns). Lower temperatures are shown in lighter greens and yellows, while higher temperatures are shown in darker reds and purples.

Six Tour de France locations analysed in the study are shown as triangles on the maps (clockwise from top): Paris, Alpe d’ Huez, Nîmes, Toulouse, Col du Tourmalet and Bordeaux.

The maps show that the maximum WBGT temperature in the afternoon has surpassed 28C over almost the entire country in the last decade. The notable exceptions to this are the mountainous regions of the Alps and the Pyrenees.

Maximum WBGT across France for the month of July from 1974-2023. Rows show the values for each decade and columns show the hourly values for 3:00pm, 4:00pm, 5:00pm and 6:00pm. Lower temperatures are shown in lighter greens and yellows, while higher temperatures are shown in darker reds and purples. Triangles indicate the six Tour de France locations analysed in the study. Source: Cvijanovic et al. (2026)

The researchers also find that most of the country has crossed the 28C WBGT threshold – which they describe as “dangerous heat levels” – on at least one July day over the past decade. However, by looking at the WBGT on the day the Tour passed through any of these six locations, they find that the threshold has rarely been breached during the race itself.

For example, the research notes that, since 1974, Paris has seen a WBGT of 28C five times at 3pm in July – but that these events have “so far” not coincided with the cycling race.

The study states that it is “fortunate” that the Tour has so far avoided the worst of the heat-stress.

Cvijanovic says the organisers and competitors have been “lucky” to date. She adds:

“It has worked really well for them so far. But as the frequency of these [extreme heat] events is increasing, it will be harder and harder to be lucky.”

Dr Madeleine Orr, an assistant professor of sport ecology at the University of Toronto who was not involved in the study, tells Carbon Brief that the paper was “really well done”, noting that its “methods are good [and its] approach was sound”. She adds:

“[The Tour has] had athletes complain about [the heat]. They’ve had athletes collapse – and still those aren’t the worst conditions. I think that that says a lot about what we consider safe. They’ve still been lucky to not see what unsafe looks like, despite [the heat] having already had impacts.”

Heat safety protocols

In 2024, the UCI set out its first-ever high temperature protocol – a set of guidelines for race organisers to assess athletes’ risk of heat stress.

The assessment places the potential risk into one of five categories based on the WBGT, ranging from very low to high risk.

The protocol then sets out suggested actions to take in the event of extreme heat, ranging from having athletes complete their warm-ups using ice vests and cold towels to increasing the number of support vehicles providing water and ice.

If the WBGT climbs above the 28C mark, the protocol suggests that organisers modify the start time of the stage, adapt the course to remove particularly hazardous sections – or even cancel the race entirely.

However, Orr notes that many other parts of the race, such as spectator comfort and equipment functioning, may have lower temperatures thresholds that are not accounted for in the protocol, but should also be considered.

Murfree points out that the study’s findings – and the heat protocol itself – are “really focused on adaptation, rather than mitigation”. While this is “to be expected”, she tells Carbon Brief:

“Moving to earlier start times or adjusting the route specifically to avoid these locations that score higher in heat stress doesn’t stop the heat stress. These aren’t climate preventative measures. That, I think, would be a much more difficult conversation to have in the research because of the Tour de France’s intimate relationship with fossil-fuel companies.”

The post Dangerous heat for Tour de France riders only a ‘question of time’ appeared first on Carbon Brief.

Dangerous heat for Tour de France riders only a ‘question of time’

Climate Change

Zeldin Celebrates Endangerment Finding Repeal With Climate Skeptics

Published

9 hours ago

April 8, 2026

Alice Rush

Casting doubt on the determination that greenhouse gas emissions endanger public health and welfare, he said, “we’re not accepting all of the narrative of the left without any question or pushback.”

By Gabriel Matias Castilho

WASHINGTON—Addressing a conference of scientists and other experts skeptical of climate change, Environmental Protection Agency Administrator Lee Zeldin on Wednesday celebrated his decision to repeal what is known as the “endangerment finding,” which provided the backbone for federal regulation of greenhouse gas emissions.

Zeldin Celebrates Endangerment Finding Repeal With Climate Skeptics

Climate Change

The Global Energy Supply in a Decade ‘Is Not a World We’re Going to Recognize’

Published

20 hours ago

April 8, 2026

Alice Rush

With the U.S. bombing Iran and the Strait of Hormuz closed, energy experts say countries transitioning to renewables will be more resilient in the “face of the shock.”

By Lisa Sorg

The United States’ war on Iran could fundamentally alter how countries consume and generate energy and hamper international progress in combating climate change, a panel of energy experts said today.

The Global Energy Supply in a Decade ‘Is Not a World We’re Going to Recognize’

Climate Change

Iran war analysis: How 60 nations have responded to the global energy crisis

Published

21 hours ago

April 8, 2026

Alice Rush

One month into the US and Israel’s war on Iran, at least 60 countries have taken emergency measures in response to the subsequent global energy crisis, according to analysis by Carbon Brief.

So far, these countries have announced nearly 200 policies to save fuel, support consumers and boost domestic energy supplies.

Carbon Brief has drawn on tracking by the International Energy Agency (IEA) and other sources to assess the global policy response, just as a temporary ceasefire is declared.

Since the start of the war in late February, both sides have bombed vital energy infrastructure across the region as Iran has blocked the Strait of Hormuz – a key waterway through which around a fifth of global oil and liquified natural gas (LNG) trade passes.

This has made it impossible to export the usual volumes of fossil fuels from the region and, as a result, sent prices soaring.

Around 30 nations, from Norway to Zambia, have cut fuel taxes to help people struggling with rising costs, making this by far the most common domestic policy response to the crisis.

Some countries have stressed the need to boost domestic renewable-energy construction, while others – including Japan, Italy and South Korea – have opted to lean more on coal, at least in the short term.

The most wide-ranging responses have been in Asia, where countries that rely heavily on fossil fuels from the Middle East have implemented driving bans, fuel rationing and school closures in order to reduce demand.

‘Largest disruption’

On 28 February, the US and Israel launched a surprise attack on Iran, triggering conflict across the Middle East and sending shockwaves around the world.

There have been numerous assaults on energy infrastructure, including an Iranian attack on the world’s largest LNG facility in Qatar and an Israeli bombing of Iran’s gas sites.

Iran’s blockade of the Strait of Hormuz, a chokepoint in the Persian Gulf, is causing what the IEA has called the “largest supply disruption in the history of the global oil market”.

A fifth of the world’s oil and LNG is normally shipped through this region, with 90% of those supplies going to destinations in Asia. Without these supplies, fuel prices have surged.

Governments around the world have taken emergency actions in response to this new energy crisis, shielding their citizens from price spikes, conserving energy where possible and considering longer-term energy policies.

Even with a two-week ceasefire announced, the energy crisis is expected to continue, given the extensive damage to infrastructure and continuing uncertainties.

Asian crunch

Carbon Brief has used tracking by the IEA, news reports, government announcements and internal monitoring by the thinktank E3G to assess the range of national responses to the energy crisis roughly one month into the Iran war.

In total, Carbon Brief has identified 185 relevant policies, announcements and campaigns from 60 national governments.

As the map below shows, these measures are concentrated in east and south Asia. These regions are facing the most extreme disruption, largely due to their reliance on oil and gas supplies from the Middle East.

The number of policies and other measures announced in response to the energy crisis. The designations employed and the presentation of the material on this map do not imply the expression of any opinion whatsoever on the part of Carbon Brief concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Source: IEA, E3G, Carbon Brief analysis.

Nations including Indonesia, Japan, South Korea and India are already spending billions of dollars on fuel subsidies to protect people from rising costs.

At least 16 Asian countries are also taking drastic measures to reduce fuel consumption. For example, the Philippines has declared a “state of national emergency”, which includes limiting air conditioning in public buildings and subsidising public transport.

Other examples from the region include the government in Bangladesh asking the public and businesses to avoid unnecessary lighting, Pakistan reducing the speed limit on highways and Laos encouraging people to work from home.

Europe – which was hit hard by the 2022 energy crisis due to its reliance on Russian gas – is less immediately exposed to the current crisis than Asia. However, many nations are still heavily reliant on gas, including supplies from Qatar.

The continent is already feeling the effects of higher global energy prices as countries compete for more limited resources.

At least 18 European nations have introduced measures to help people with rising costs. Spain, which is relatively insulated from the crisis due to the high share of renewables in its electricity supply, nevertheless announced a €5bn aid package, with at least six measures to support consumers.

Many African countries, while also less reliant on direct fossil-fuel supplies via the Strait of Hormuz than Asia, are still facing the strain of higher import bills. Some, including Ethiopia, Kenya and Zambia, are also facing severe fuel shortages.

There have been fewer new policies across the Americas, which have been comparatively insulated from the energy crisis so far. One outlier is Chile, which is among the region’s biggest fuel importers and is, therefore, more exposed to global price increases.

Tax cuts

The most common types of policy response to the energy crisis so far have been efforts to protect people and businesses from the surge in fuel prices.

At least 28 nations, including Italy, Brazil and Australia, have introduced a total of 31 measures to cut taxes – and, therefore, prices – on fuel.

Even across Africa, where state revenues are already stretched, some nations – including Namibia and South Africa – are cutting fuel levies in a bid to stabilise prices.

Another 17 countries, including Mexico and Poland, have directly capped the price of fuel. Others, such as France and the UK, have opted for more targeted fuel subsidies, designed to support specific vulnerable groups and industries.

These measures are all shown in the dark blue “consumer support” bars in the chart below.

Number of policies and measures announced by 60 countries, with shades of blue indicating the broad objective of the policy. Source: IEA, E3G, Carbon Brief analysis.

Such measures can directly help consumers, but some leaders, NGOs and financial experts have noted that there is also the risk of them driving inflation and reinforcing reliance on the existing fossil fuel-based system.

Christine Lagarde, president of the European Central Bank, spoke in favour of short-term measures to “smooth the shock”, but noted that “broad-based and open-ended measures may add excessively to demand”.

Measures to conserve energy, of the type that many developing countries in Asia have implemented extensively, have been described by the IEA as “more effective and fiscally sustainable than broad-based subsidies”.

So far, there have been at least 23 such measures introduced to limit the use of transport, particularly private cars.

These include Lithuania cutting train fares, two Australian states making public transport free and Myanmar and South Korea asking people to only drive their cars on certain days.

Clean vs coal

At least eight countries have announced plans to either increase their use of coal or review existing plans to transition away from coal, according to Carbon Brief’s analysis. These include Japan, South Korea, Bangladesh, the Philippines, Thailand, Pakistan, Germany and Italy.

These measures broadly involve delaying coal-plant closure, as in Italy, or allowing older sites to operate at higher rates, as in Japan – rather than building more coal plants.

There has been extensive coverage of how the energy crisis is “driving Asia back to coal”. However, as Bloomberg columnist David Fickling has noted, this shift is relatively small and likely to be offset by a move to cheap solar power in the longer term.

Indeed, some countries have begun to consider changes to the way they use energy going forward, amid a crisis driven by the spiralling costs of fossil-fuel imports.

Leaders in India, Barbados and the UK have explicitly stressed the importance of a structural shift to using clean power. Governments in France and the Philippines are among those linking new renewable-energy announcements with the unfolding crisis.

New renewable-energy capacity will take time to come online, albeit substantially less time than developing new fossil-fuel generation. In the meantime, some nations are also taking short-term measures to make their road transport less reliant on fossil fuels.

For example, the Chilean government has enabled taxi drivers to access preferential credit for purchasing electric vehicles (EVs). Cambodia has cut import taxes on EVs and Laos has lowered excise taxes on them.

Finally, there have been some signs that countries are reconsidering their future exposure to imported fossil fuels, given the current economics of oil and gas.

The New Zealand government has indicated that a plan to build a new LNG terminal by 2027 now faces uncertainty. Reuters reported that Vietnamese conglomerate Vingroup has told the government it wanted to abandon a plan to build a new LNG-fired power plant in Vietnam, in favour of renewables.