Fahad Saeed is a climate impact scientist for Climate Analytics, based in Islamabad, and Bill Hare is CEO and senior scientist at Climate Analytics.
Pakistan’s southern province of Sindh has been sweltering under 52°C heat in recent days. Not in the news however is that wet-bulb temperatures in the region – a more accurate indicator of risk to human health that accounts for heat and humidity – passed a key danger threshold of 30°C.
Climate change is increasing the risk of deadly humid heat in developing countries like Pakistan, Mexico and India, and without international support to adapt, vulnerable communities could face catastrophe.
What is wet-bulb temperature?
Wet-bulb temperature is an important scientific heat stress metric that accounts for both heat and humidity. When it’s both hot and humid, sweating – the body’s main way of cooling – becomes less effective as there’s too much moisture in the air. This can limit our ability to maintain a core temperature of 37°C – something we all must do to survive.
A recent study suggests that wet-bulb temperatures beyond 30°C pose severe risks to human health, but the hard physiological limit comes at prolonged exposure (about 6-8 hours) to wet-bulb temperatures of 35°C. At this point, people can experience heat strokes, organ failure, and in extreme cases, even death.
Climate change and deadly heat
Globally, around 30% of people are exposed to lethal humid heat. This could reach as much as 50% by 2100 due to global warming. To date, the climate has warmed around 1.3°C as a result of human activity, primarily due to the burning of fossil fuels. And along with the extra heat, with every 1°C rise the air can hold up to 7% more moisture.
A comprehensive evaluation of global weather station data reveals that the frequency of extreme humid heat has more than doubled since 1979, with several wet-bulb exceedances of 31-33°C. Another recent study predicts a surge in the frequency and geographic spread of extreme heat events, even at 1.5°C warming.
Rich nations meet $100bn climate finance goal – two years late
What this shows is that the humid tropics including monsoon belts are all careening towards the 35°C threshold, which is very worrying for countries like Pakistan. The city of Jacobabad has already breached 35°C wet bulb temperatures many times. More areas of the country are likely to be exposed to such life-threatening conditions more often due to climate change.
At 1.5°C of warming, much of South Asia, large parts Sahelian Africa, inland Latin America and northern Australia could be subject to at least one day per year of lethal heat. If the world gets to 3°C, this exposure explodes, covering most of South Asia, large parts of Eastern China and Southeast Asia, much of central and west Africa, most of Latin America and Australia and significant parts of the southeastern USA and the Gulf of Mexico.
Areas of the world that will experience at least one day of deadly heat per year at different levels of warming

Source: ScienceAdvances
Even at 1.5°C of warming, there will be high exposure to lethal heat in large regions where billions presently live. This terrible threat to human life calls for urgent action to limit warming and help at risk communities adapt.
Adapting to hard limits
While 35°C can prove deadly, one study suggests a 32°C wet-bulb threshold as the hard limit for labour. More realistic, human-centred models found this overly optimistic, as direct exposure and other vulnerability factors were ignored. Vulnerable groups including unskilled labourers would be most at risk of losing their income.
In densely populated urban centres, lethal humid heat is not just a future projection but a current reality. This calls for urgent adaptation measures which integrate the risk of deadly heat into urban planning, public health, early-warning systems and emergency response.
Investments in green spaces, heat-resilient buildings and urban cooling are vital adaptation strategies. Community initiatives like awareness campaigns, indigenous cooling strategies and local heat action plans are also essential. Households could consider investing in cooling technologies or migrating – options mostly available to the wealthy.
In Malawi, dubious cyclone aid highlights need for loss and damage fund
As climate change makes lethal humid heat a growing threat in some of the world’s most populous areas, more attention must be paid to understanding its risks – especially in vulnerable regions with huge data gaps. This demands a multidimensional response that combines scientific research, policymaking and community engagement.
The potential scale and level of risk to human life also reinforces the importance of ensuring that the Paris Agreement’s 1.5°C global warming limit is met. To do this, we need to halve emissions by 2030. Countries should therefore strengthen their 2030 emissions targets in line with the warming limit as they prepare equally ambitious 2035 targets in updated NDCs.
The Pakistan heatwave is a terrible reminder of this often-underestimated threat. We must act now to limit warming while we adapt to the growing danger of deadly heat if we are to avoid potentially wide-reaching tragedies in the future.
The post Developing countries need support adapting to deadly heat appeared first on Climate Home News.
Climate Change
Greenpeace’s Dutch Anti-SLAPP Case Against Oil Pipeline Giant Advances
But a $345 million U.S. verdict against the environmental group hangs over the case.
A lawsuit filed by Greenpeace International against the U.S.-based fossil fuel company Energy Transfer in the Netherlands is moving forward after a Dutch court recently ruled in favor of the environmental organization in rejecting the company’s bid to toss out the case.
Greenpeace’s Dutch Anti-SLAPP Case Against Oil Pipeline Giant Advances
Climate Change
The Search for Super Reefs
Go behind the scenes with executive editor Vernon Loeb and oceans correspondent Teresa Tomassoni as they discuss the search for heat-resilient coral reefs that are somehow defying the odds to survive a warming planet.
The world has already lost more than half of its coral reefs, and most of what remains is at risk of disappearing in the next 25 years.
Climate Change
DeBriefed 19 June 2026: Bonn talks end in ‘gridlock’ | Energy’s ‘new era’ | Oceans in climate negotiations
Welcome to Carbon Brief’s DeBriefed.
An essential guide to the week’s key developments relating to climate change.
This week
Bonn talks close
‘SIDE-STEPPING AND STALLING’: UN climate talks in Bonn have ended in “gridlock”, according to Climate Home News. The outlet reported on the failure to balance developing countries’ need for climate-adaptation finance with “richer nations’ desire to move forward” on emissions cuts. It added that both topics were subject to “rule 16”, meaning no agreement could be reached and work will be pushed to the COP31 summit in Turkey. Inside Climate News quoted UN climate executive secretary Simon Stiell, who said the talks had seen “side-stepping and stalling”.
JUST TRANSITION: One “glimmer of hope” came from negotiations on achieving a “just transition”, reported Euronews. The news outlet said negotiators “made headway on operationalising the Belém-Antalya mechanism”, intended to support people in the shift to a low-carbon economy. However, Politico concluded that much of the focus in Bonn had “shift[ed] to efforts outside diplomatic talks – raising questions about the future of global climate negotiations”.
‘ATTACKING SCIENCE’: Agence France-Presse reported on the EU, Switzerland and “dozens of developing nations” warning of “attacks on science” by a “small group of fossil-fuels interests” in Bonn. Table Briefings explained that “the 1.5C target is increasingly being challenged” and the role of the UN climate-science panel – the Intergovernmental Panel on Climate Change (IPCC) – in an upcoming assessment of global climate progress “remains controversial”. See Carbon Brief’s full write-up of the talks for more detail.
US-Iran deal
PRICE DROP: The US and Iran announced that they have reached an interim agreement to halt the war and reopen the strait of Hormuz, reported Bloomberg. Oil prices have fallen, as the “long-awaited deal” began the process of “eas[ing]” the global energy crisis triggered by the conflict, according to the New York Times. The Associated Press noted that high fuel prices will “likely outlast the Iran war”.
‘OIL GLUT’: The Financial Times reported that the International Energy Agency (IEA) has forecast a “glut of oil” emerging next year, if the peace deal holds. The IEA said this would allow countries to build new strategic reserves, as they “review their energy strategies and policies in response to the crisis”, according to Reuters.
‘NEW ERA’: Agence France-Presse reported that oil and gas companies have “few illusions about a return to normal for the Gulf energy industry after more than three months of blockage”. One analyst told the newswire that the war “showed the oil and gas industry that Hormuz risk is no longer just a geopolitical headline”.
Around the world
- OCEAN MONITOR: The Trump administration is “abandoning its plan” to dismantle a $368m ocean monitoring system key for tracking climate change after a “bipartisan backlash on Capitol Hill”, reported the New York Times.
- CORAL HAVEN: The New York Times covered preliminary research, presented at the Our Ocean Conference in Kenya, suggesting there could be three times as many “coral refugia” – where corals are relatively safe from climate change – than previously thought.
- BAD CREDIT: Down to Earth reported that the first carbon credits issued under the Paris Agreement’s new Article 6.4 mechanism are “facing scrutiny over alleged links to institutions controlled by Myanmar’s military junta”.
- OIL BACKTRACK: Reuters reported that oil-and-gas company Equinor has dropped a renewable-energy target and scaled back clean investments, while another Reuters story noted that Shell is selling off its offshore wind assets.
1.1 billion
The number of children facing “at least three overlapping climate hazards”, according to a new Unicef report covered by Agence France-Presse.
Latest climate research
- Including the “permafrost carbon-climate feedback” in climate models increases the chance of exceeding “tipping elements” – such as the Greenland ice sheets, Atlantic Meridional Overturning Circulation or Amazon rainforest – by up to 50% | Environmental Research Letters
- The intensity of influenza outbreaks could decline in temperate regions, but increase in tropical areas over the next century, as the climate warms | PNAS Nexus
- European snow cover has declined by 20% for December and January since the start of the industrial era, revealing an “unprecedented ongoing shrinkage of European winters” | Communications Earth & Environment
(For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Monday, Tuesday, Wednesday, Thursday and Friday.)
Captured
The more than 2m battery electric vehicles (BEVs), 1m “plug-in” hybrids (PHEVs) and 100,000 electric vans on UK roads are already saving drivers a total of around £3bn a year, according to new Carbon Brief analysis. This amounts to savings of more than £1,100 a year in fuel costs for each BEV driver in the UK. The analysis comes amid reports in UK media this week that the government is considering “watering down” its EV sales targets.
Spotlight
Oceans rising at UN climate talks
The state of the world’s oceans is inextricably linked to the changing climate – and many delegates at UN climate talks want to see more focus on this issue, reports Carbon Brief.
Oceans are often described as the world’s “greatest ally” against climate change – absorbing 30% of carbon dioxide (CO2) emissions and most of the heat generated by those emissions.
They are also the site of important climate solutions, such as huge offshore windfarms and the shipping industry’s transition to cleaner fuels.
At the same time, the oceans themselves present a growing danger to coastal communities and sea life due to sea level rise, marine heatwaves and ocean acidification.
These diverse issues have led to growing calls within the UN climate process for more focus on oceans. During climate negotiations this week in Bonn – known as SB64 – nations and civil society had a chance to air these views during an “ocean and climate change dialogue”.
‘Elevate action’
Oceans first entered UN climate outcomes in 2019, when the final COP25 negotiated text requested a new “dialogue” on “the ocean and climate change to consider how to strengthen mitigation and adaptation action”.
The following years saw this dialogue established as an annual event. However, the political weight of these discussions has been limited.
COP31 is being co-led by Turkey and Australia, but with Pacific islands playing a supporting role. These small islands sometimes self-identify as “large ocean states”, stressing the ocean’s centrality in their societies.
In Bonn, figures from across the presidency threw their weight behind this issue. Chris Bowen, an Australian minister and incoming COP31 “president of negotiations”, told attendees:
“Australia, Turkey and the Pacific see an important opportunity to elevate ocean-based climate action.”

Strategies and finance
The two-day dialogue in Bonn involved a series of panels, statements and breakout groups.
One of the main topics was how oceans are integrated into national climate plans under the Paris Agreement, known as “nationally determined contributions” (NDCs).
Three-quarters of the latest round of NDCs mention oceans, with conservation of “blue carbon” ecosystems the most frequently described action. (Landscapes such as mangroves can both absorb CO2 and protect coastal areas.)
Delegates also discussed alignment with the UN biodiversity process, as well as ocean finance, which currently makes up less than 1% of all climate finance.
(As discussions were taking place in Bonn, country officials also gathered in Mombasa, Kenya for the 11th Our Ocean Conference. Carbon Brief’s associate editor Giuliana Viglione attended the conference and will publish a full summary shortly.)
Developing countries were clear that many of the ocean-related actions in their NDCs would depend on receiving more financial support.
‘Political momentum’
With the backing of the COP31 presidency, delegates were hopeful about where this year’s dialogue could lead.
Charles Hamilton, an advisor for the Bahamas who spoke for the Alliance of Small Island States (AOSIS) in the dialogue, told Carbon Brief that island representatives “are not traveling thousands of miles to just talk and pat ourselves on the back”. He added:
“A dialogue that just remains a dialogue is just more talk – no action.”
Given that, he said “discussions in the dialogue must move into COP decisions and the decisions must be actioned”, noting the importance of finance.
Marina Corrêa, oceans lead at WWF-Brazil, pointed to an upcoming UN climate change Standing Committee on Finance forum as a space to ramp up pressure on ocean finance.
More broadly, she wanted to see the presidencies translate their support into a “leader-level ocean initiative” that could “mainstream” oceans across negotiations.
“We have a really interesting opportunity, in terms of political momentum,” Corrêa told Carbon Brief.
Watch, read, listen
‘HOTTER THAN HELL’: An episode of the BBC’s Rare Earth podcast titled “hotter than hell” considered the issue of extreme heat, with input from experts and “people facing up to the hottest temperatures on the planet”.
NOT BROKEN?: John Drake, a professor of ecology at the University of Georgia, wrote an essay for Aeon – also re-published as a Guardian “long read” – questioning the framing of ecosystems and climate systems “breaking down”.
ON COURSE: On his Volts podcast, US climate journalist David Roberts interviewed UK climate minister Katie White, quizzing her about whether the UK will “stay the course with its climate plans”.
Coming up
- 20-28 June: London climate action week
- 21 June: Colombia presidential runoff
- 24 June: UK Climate Change Committee progress in reducing emissions 2026 report to parliament
Pick of the jobs
- Mongabay, managing editor – Africa | Salary: Unknown. Location: Global
- Contexte, environment reporter – Brussels | Salary: €45,000-€60,000. Location: Brussels
- Climate 200, communications director | Salary: Unknown. Location: Australia
- Energy Tracker Asia, energy transition correspondent | Salary: $3,000-$4,000 per month. Location: South-east Asia (remote)
DeBriefed is edited by Daisy Dunne. Please send any tips or feedback to debriefed@carbonbrief.org.
This is an online version of Carbon Brief’s weekly DeBriefed email newsletter. Subscribe for free here.
The post DeBriefed 19 June 2026: Bonn talks end in ‘gridlock’ | Energy’s ‘new era’ | Oceans in climate negotiations appeared first on Carbon Brief.
-
Greenhouse Gases10 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Climate Change10 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Greenhouse Gases2 years ago嘉宾来稿:满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago嘉宾来稿:满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago
Bill Discounting Climate Change in Florida’s Energy Policy Awaits DeSantis’ Approval
-
Renewable Energy8 months agoSending Progressive Philanthropist George Soros to Prison?
-
Carbon Footprint2 years agoUS SEC’s Climate Disclosure Rules Spur Renewed Interest in Carbon Credits
-
Greenhouse Gases11 months ago
嘉宾来稿:探究火山喷发如何影响气候预测


