Welcome to Carbon Brief’s DeBriefed.
An essential guide to the week’s key developments relating to climate change.
This week
Pakistan and India floods
EXTREME WEATHER: Heavy flooding forced half a million people to evacuate their homes in just 24 hours in Pakistan’s Punjab this week, the Associated Press reported. It brings the total number of people displaced since last month to 1.8 million, the newswire said. According to Arab News, at least 41 people have died as a result of the flooding since last week. The flooding has also destroyed thousands of acres of crops in Punjab, a province that accounts for 68% of Pakistan’s total annual food grain production, Bloomberg reported.
CROSS-BORDER EVENT: Meanwhile, in Indian Punjab, “at least 30 people have died and more than 354,000 have been affected” by flooding, BBC News reported. India also warned Pakistan about more cross-border flooding for the second time in as many weeks, as both countries reeled from monsoon rains, the Associated Press reported.
UK dividing lines
NEW FACE: Zack Polanski has been elected as the new leader of the Green Party of England and Wales in a landslide victory, the Financial Times reported. Polanski is an “outspoken campaigner who has argued his party needs to ‘connect with people’s anger’ and become more combative against ‘villains’, including oil major Shell and the ‘super-rich’”, the newspaper said. Polanksi wants to “replace” the ruling Labour party on a platform of “eco-populism”, according to BBC News.
NORTH SEA OIL: Meanwhile, the UK Conservative leader Kemi Badenoch pledged to drill “all” of the remaining oil and gas in the North Sea if elected, BBC News reported. [The Conservatives are polling third, at 17%.] In response to the speech, the Daily Telegraph‘s world economy editor Ambrose Evans-Pritchard argued that Badenoch’s plan would not “raise this country’s long-term output of oil and gas by more than homeopathic amounts” nor “move the needle on UK energy prices” (more below).
Around the world
- HIGHER AMBITIONS: The UN urged countries to set new, more ambitious national climate plans this month, ahead of this year’s COP30 summit in Belém, Brazil, Reuters reported.
- ‘JUNK SCIENCE’: A group of more than 85 climate scientists released a “scathing review” of the Trump administration’s misleading climate report, DeSmog reported.
- FOSSIL ENERGY: Russia said China had agreed to a massive new pipeline capable of importing as much as 50bn cubic metres of gas a year, the Financial Times reported.
- US PRESSURE: Reuters reported that the US is pressuring other countries to reject a UN deal on cutting emissions from shipping by threatening them with tariffs, visa restrictions and port levies.
- SWELTERING HEAT: Authorities in Japan and South Korea said 2025 was the hottest summer in their countries since records began, Al Jazeera reported.
- MITIGATION WORK: According to Bloomberg, Zimbabwe has published draft regulations to establish a National Climate Fund. The fund will finance projects “aimed at mitigating the impact of climate change and respond[ing] to emergencies”.
20%
The amount by which clean-energy production has surged in India this year, according to Reuters, citing data from the thinktank Ember.
Latest climate research
- “Extreme cold surges” have “robustly weakened in middle-to-high latitude continents during autumn and winter” due to climate change, according to a study in Nature Communications.
- A study published in npj Climate Action found that exposing people to moral appeals results in overall carbon footprint reduction and increased participation in civic and political climate action, regardless of ideological affiliation.
- The World Bank’s increase in climate finance spending since the Paris Agreement has been driven by projects with “low climate components”, according to a study in Climatic Change.
(For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Monday, Tuesday, Wednesday, Thursday and Friday.)
Captured
A claim that gas produced in the North Sea emits “four times” less CO2 than imported liquified natural gas (LNG) featured prominently in both the Guardian and the Daily Telegraph this week, following Badenoch’s pledge to drill “all” the remaining oil and gas in the UK. However, this figure is highly misleading. It only refers to the emissions that come from the process of extracting and delivering the gas, which are much smaller than those from burning it. When both extraction and burning of the gas are taken into account, CO2 emissions from UK production are only around 15% lower than those from LNG imports, according to a new factcheck from Carbon Brief.
Spotlight
A man-made lake threatened by climate change
This week, Carbon Brief reports on how climate change is impacting the sustainability of a scenic nature reserve in the southern US.
In 1941, as World War 2 thickened, the US Congress approved a plan to construct a reservoir storage project on the Hiwassee River, a water body that cuts across the states of Georgia, North Carolina and Tennessee.
The dam, which came to be known as Chatuge after an 18th-century Cherokee village, was originally built for power generation purposes. However, after it was completed, it became more than a hydroelectric project.
In May 1942, the Towns County Lions Club started stocking fish in the newly created Lake Chatuge. In 1944, Clay County leased a tract of land for a public park.
Today, the park offers “scenic mountain views” and “panoramic views” of Lake Chatuge. The lake is also home to rare, endangered plant species and is an important source of drinking water.
However, Lake Chatuge’s future has been plunged into uncertainty after the Tennessee Valley Authority proposed a plan to repair the dam’s spillway, which could involve draining the lake’s water levels by 20 feet (6m) for up to eight years.
The TVA’s action is largely forward-thinking. While the dam and its spillway are in good condition, the public utility company is wary of extreme weather events made more likely by climate change.
In September 2024, Hurricane Helene tore through parts of Georgia and North Carolina, leaving more than 128 people dead across the US and uprooting communities in its wake. One analysis estimated that 44% of the economic damage from the storm can be attributed to human-caused climate change.
The Lake Chatuge area was largely spared, but officials worry that the next extreme weather event may not be far off.
“It’s the kind of event – the unusual storm event that can happen, that’s pretty rare – is what we’re looking out for,” a TVA project manager has said.
Meanwhile, aside from the imminent repairs made more likely by the increased possibility of extreme weather events, Lake Chatuge is also battling a parrot feather infestation, a phenomenon involving the spread of an invasive plant that has been linked to global warming in other parts of the US.
Saving Lake Chatuge
The threat posed by climate change to Lake Chatuge is not an isolated case. A July 2025 report by researchers at Utah State University found that climate change is affecting the social benefits of dams across the country.
Elsewhere in the world, the impact of extreme weather on ageing dams is wide ranging, including recently heightening tensions between India and Pakistan.
However, community members in the Lake Chatuge area are not giving up easily. A Facebook group dedicated to saving the lake has more than 2,000 members.
“Lake Chatuge is our economy,” Towns County’s sole commissioner, Cliff Bradshaw, told Carbon Brief. He added:
“The main attraction to this area is Lake Chatuge. Without the lake, the county’s tourism would drop, and our economy would suffer greatly – could even drive the county into a depression – as we have a great deal of businesses that rely solely on activities on Lake Chatuge for their customers, such as marinas, party boats and water activity playgrounds. The other businesses in town may not rely on the lake for customers, but do rely on the tourist traffic brought into the area by the lake to drive customers into their place of business.”
According to reporting by the Atlanta-Journal Constitution, visitors have spent up to $100m annually in the area since 2021.
The TVA’s repair work could begin as soon as 2027, but community members are asking both the public utility company and political leaders to help find the least damaging pathway.
Watch, read, listen
SCIENCE CUTS: The Financial Times reported on how the Trump administration has “gutted” the Federal Emergency Management Agency (Fema), throwing into doubt the nation’s ability to respond to extreme weather disasters.
SUSTAINABLE ECONOMICS: In an interview with Le Monde, the French economist Thomas Piketty argued that protecting the planet from climate change requires wealth redistribution.
TWEAKING NATURE: A Havard atmospheric chemist and an Oxford planetary physicist discussed the nuances and subtleties of geoengineering on the podcast Entanglements by Undark.
Coming up
- 8 September: Norway election
- 8-12 September: 54th Pacific Islands Forum Leaders Meeting, Honoraria, Solomon Islands
- 9-23 September: 80th Session of the UN General Assembly, New York
Pick of the jobs
- Energy UK, policy manager | Salary: £38,450. Location: London
- CNN Digital, climate and weather editor | Salary: $91,000-$169,000. Location: Atlanta, Washington DC, New York, Chicago or Burbank, California
- The Post and Courier, rising waters reporter | Salary: Unknown. Location: South Carolina, US
- The Seattle Times, climate reporter | Salary: $75,000-$90,000. Location: Seattle, US
DeBriefed is edited by Daisy Dunne. Please send any tips or feedback to debriefed@carbonbrief.org.
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The post DeBriefed 5 September 2025: Pakistan floods hit 1.8m people; UK ‘eco-populism’; How warming threatens a man-made lake appeared first on Carbon Brief.
Drought and heatwaves occurring together – known as “compound” events – have “surged” across the world since the early 2000s, a new study shows.
Compound drought and heat events (CDHEs) can have devastating effects, creating the ideal conditions for intense wildfires, such as Australia’s “Black Summer” of 2019-20 where bushfires burned 24m hectares and killed 33 people.
The research, published in Science Advances, finds that the increase in CDHEs is predominantly being driven by events that start with a heatwave.
The global area affected by such “heatwave-led” compound events has more than doubled between 1980-2001 and 2002-23, the study says.
The rapid increase in these events over the last 23 years cannot be explained solely by global warming, the authors note.
Since the late 1990s, feedbacks between the land and the atmosphere have become stronger, making heatwaves more likely to trigger drought conditions, they explain.
One of the study authors tells Carbon Brief that societies must pay greater attention to compound events, which can “cause severe impacts on ecosystems, agriculture and society”.
Compound events
CDHEs are extreme weather events where drought and heatwave conditions occur simultaneously – or shortly after each other – in the same region.
These events are often triggered by large-scale weather patterns, such as “blocking” highs, which can produce “prolonged” hot and dry conditions, according to the study.
Prof Sang-Wook Yeh is one of the study authors and a professor at the Ewha Womans University in South Korea. He tells Carbon Brief:
“When heatwaves and droughts occur together, the two hazards reinforce each other through land-atmosphere interactions. This amplifies surface heating and soil moisture deficits, making compound events more intense and damaging than single hazards.”
CDHEs can begin with either a heatwave or a drought.
The sequence of these extremes is important, the study says, as they have different drivers and impacts.
For example, in a CDHE where the heatwave was the precursor, increased direct sunshine causes more moisture loss from soils and plants, leading to a drought.
Conversely, in an event where the drought was the precursor, the lack of soil moisture means that less of the sun’s energy goes into evaporation and more goes into warming the Earth’s surface. This produces favourable conditions for heatwaves.
The study shows that the majority of CDHEs globally start out as a drought.
In recent years, there has been increasing focus on these events due to the devastating impact they have on agriculture, ecosystems and public health.
In Russia in the summer of 2010, a compound drought-heatwave event – and the associated wildfires – caused the death of nearly 55,000 people, the study notes.
The record-breaking Pacific north-west “heat dome” in 2021 triggered extreme drought conditions that caused “significant declines” in wheat yields, as well as in barley, canola and fruit production in British Columbia and Alberta, Canada, says the study.
Increasing events
To assess how CDHEs are changing, the researchers use daily reanalysis data to identify droughts and heatwaves events. (Reanalysis data combines past observations with climate models to create a historical climate record.) Then, using an algorithm, they analyse how these events overlap in both time and space.
The study covers the period from 1980 to 2023 and the world’s land surface, excluding polar regions where CDHEs are rare.
The research finds that the area of land affected by CDHEs has “increased substantially” since the early 2000s.
Heatwave-led events have been the main contributor to this increase, the study says, with their spatial extent rising 110% between 1980-2001 and 2002-23, compared to a 59% increase for drought-led events.
The map below shows the global distribution of CDHEs over 1980-2023. The charts show the percentage of the land surface affected by a heatwave-led CDHE (red) or a drought-led CDHE (yellow) in a given year (left) and relative increase in each CDHE type (right).
The study finds that CDHEs have occurred most frequently in northern South America, the southern US, eastern Europe, central Africa and south Asia.
Threshold passed
The authors explain that the increase in heatwave-led CDHEs is related to rising global temperatures, but that this does not tell the whole story.
In the earlier 22-year period of 1980-2001, the study finds that the spatial extent of heatwave-led CDHEs rises by 1.6% per 1C of global temperature rise. For the more-recent period of 2022-23, this increases “nearly eightfold” to 13.1%.
The change suggests that the rapid increase in the heatwave-led CDHEs occurred after the global average temperature “surpasse[d] a certain temperature threshold”, the paper says.
This threshold is an absolute global average temperature of 14.3C, the authors estimate (based on an 11-year average), which the world passed around the year 2000.
Investigating the recent surge in heatwave-leading CDHEs further, the researchers find a “regime shift” in land-atmosphere dynamics “toward a persistently intensified state after the late 1990s”.
In other words, the way that drier soils drive higher surface temperatures, and vice versa, is becoming stronger, resulting in more heatwave-led compound events.
Daily data
The research has some advantages over other previous studies, Yeh says. For instance, the new work uses daily estimations of CDHEs, compared to monthly data used in past research. This is “important for capturing the detailed occurrence” of these events, says Yeh.
He adds that another advantage of their study is that it distinguishes the sequence of droughts and heatwaves, which allows them to “better understand the differences” in the characteristics of CDHEs.
Dr Meryem Tanarhte is a climate scientist at the University Hassan II in Morocco, and Dr Ruth Cerezo Mota is a climatologist and a researcher at the National Autonomous University of Mexico. Both scientists, who were not involved in the study, agree that the daily estimations give a clearer picture of how CDHEs are changing.
Cerezo-Mota adds that another major contribution of the study is its global focus. She tells Carbon Brief that in some regions, such as Mexico and Africa, there is a lack of studies on CDHEs:
“Not because the events do not occur, but perhaps because [these regions] do not have all the data or the expertise to do so.”
However, she notes that the reanalysis data used by the study does have limitations with how it represents rainfall in some parts of the world.
Compound impacts
The study notes that if CDHEs continue to intensify – particularly events where heatwaves are the precursors – they could drive declining crop productivity, increased wildfire frequency and severe public health crises.
These impacts could be “much more rapid and severe as global warming continues”, Yeh tells Carbon Brief.
Tanarhte notes that these events can be forecasted up to 10 days ahead in many regions. Furthermore, she says, the strongest impacts can be prevented “through preparedness and adaptation”, including through “water management for agriculture, heatwave mitigation measures and wildfire mitigation”.
The study recommends reassessing current risk management strategies for these compound events. It also suggests incorporating the sequences of drought and heatwaves into compound event analysis frameworks “to enhance climate risk management”.
Cerezo-Mota says that it is clear that the world needs to be prepared for the increased occurrence of these events. She tells Carbon Brief:
“These [risk assessments and strategies] need to be carried out at the local level to understand the complexities of each region.”
The post Heatwaves driving recent ‘surge’ in compound drought and heat extremes appeared first on Carbon Brief.
Heatwaves driving recent ‘surge’ in compound drought and heat extremes
Greenhouse Gases
DeBriefed 6 March 2026: Iran energy crisis | China climate plan | Bristol’s ‘pioneering’ wind turbine
Welcome to Carbon Brief’s DeBriefed.
An essential guide to the week’s key developments relating to climate change.
This week
Energy crisis
ENERGY SPIKE: US-Israeli attacks on Iran and subsequent counterattacks across the Middle East have sent energy prices “soaring”, according to Reuters. The newswire reported that the region “accounts for just under a third of global oil production and almost a fifth of gas”. The Guardian noted that shipping traffic through the strait of Hormuz, which normally ferries 20% of the world’s oil, “all but ground to a halt”. The Financial Times reported that attacks by Iran on Middle East energy facilities – notably in Qatar – triggered the “biggest rise in gas prices since Russia’s full-scale invasion of Ukraine”.
‘RISK’ AND ‘BENEFITS’: Bloomberg reported on increases in diesel prices in Europe and the US, speculating that rising fuel costs could be “a risk for president Donald Trump”. US gas producers are “poised to benefit from the big disruption in global supply”, according to CNBC. Indian government sources told the