We handpick and explain the most important stories at the intersection of climate, land, food and nature over the past fortnight.
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Key developments
High Seas Treaty milestone
OCEAN PROTECTION: The High Seas Treaty, which aims to “protect the world’s oceans and reverse damage to marine life”, will take effect next January after reaching a key milestone, BBC News reported. Morocco brought the global agreement, which was approved in 2023, to the threshold of 60 ratifications required for it to take effect. The broadcaster said: “Environmentalists heralded the milestone as a ‘monumental achievement’ and evidence that countries can work together for environmental protection.” UN chief António Guterres described it as a “lifeline for the ocean and humanity”, according to Al Jazeera.
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CLIMATE WEEK: Meanwhile, Chile and the UK joined a number of countries who have “committed to promoting ocean-based actions” in their respective national climate plans, Inside Climate News reported. Speaking at a New York Climate Week event, officials said they are considering many steps including phasing out offshore oil and gas drilling, decarbonising shipping and committing to marine ecosystem conservation. According to another Inside Climate News story, many Climate Week events are “centred around” regenerative agriculture – a method of farming that prioritises soil quality and ecosystem biodiversity. The term is now a “ubiquitous buzzword…increasingly deployed on marketing labels”, the outlet said.
OVERFISHING: Elsewhere, a “long-wrought” global agreement “aimed at reducing overfishing” took effect earlier this month, the Associated Press reported. The World Trade Organization agreement on fisheries subsidies entered into force after it was adopted by 112 countries. The AP noted that the agreement “will require countries to limit some of the $22bn in subsidies worldwide that encourage practices by fleets that deplete fish stocks and will create a ‘fish fund’ that can help developing countries implement it”. An article in the Conversation said the agreement is a “major milestone, but it’s only the beginning”.
‘Erratic’ water cycle
DELUGE TO DROUGHT: Almost two-thirds of the world’s rivers did not experience “normal” conditions in 2024, dealing with either too much or too little water, according to the World Meteorological Organization’s state of global water resources report. In its coverage, Al Jazeera said that “climate change is making the Earth’s water cycle increasingly erratic”. The report, the outlet noted, said that 2024 was the sixth year in a row with a “clear imbalance” in river basins. It was also the third consecutive year of widespread ice loss in every glacier region, the report said.
WATER IMPACTS: The report said that floods hindered agriculture in many regions in 2024, including impacting wheat harvests in Afghanistan and sweeping away almost 130,000 cows in west and central Africa. CNN’s coverage said the findings highlight “big trouble for economies and societies” dealing with the impacts of a less-predictable water cycle.. Last year was the hottest on record, with many regions “grappl[ing] with a dearth of water”, the outlet noted. Other regions, however, experienced “more floods than in other years”, a lead author on the report, Prof Stefan Uhlenbrook, told CNN. He added that some of these floods caused billions of dollars in damage.
FLOOD AFTERMATH: Meanwhile, major floods in Pakistan’s Punjab province have “wreaked havoc” on agriculture, impacting more than half a million hectares of farming land, according to the Nation. The Pakistani newspaper reported that the floods, covered in last month’s Cropped, “devastat[ed]” crops including cotton, rice, sugarcane and maize. Around 6% of Punjab’s farmland was damaged by recent floods, the newspaper said. Reuters reported that at least 220,000 hectares of rice fields flooded from the deluge between August and September. In India’s Punjab state, farmers are also dealing with the impacts of the “worst floods in four decades”, Al Jazeera said.
News and views
CASH FOR NATURE: The UK spent a record £800m on “nature protection and restoration” as part of climate aid spending last year, according to government figures obtained by Carbon Brief. The figures suggested that the country is on track to achieve its five-year pledge to provide £3bn in nature-related funds for developing countries by 2026. Meanwhile, a report from Wildlife and Countryside Link found that 38% of UK waters are in protected areas, but just 6% of land is – “far short” of the target to protect 30% of the country’s land and sea by 2030, the report said.
DEFORESTATION DELAYS: The European Commission has proposed a further one-year delay to the implementation of its anti-deforestation law, Reuters reported. The law, which is currently due to take effect this December, was already postponed by one year in late 2024. Reuters said that the commission cited concerns about IT systems. The outlet noted that both the European parliament and a majority of EU member states “must approve the delay”.
GROWING FOOD: This year looks set to see record-high production of corn, wheat, soya beans and rice, according to analysis by data scientist Dr Hannah Ritchie on her Substack, Sustainability by numbers. Looking at agricultural projections from the US Department of Agriculture, Ritchie noted that decades of steady production increases in most crops, “with the exception of sorghum and millet”, are expected to continue. Elsewhere, Australia’s ABC News reported on a new climate risk assessment that identified future farming impacts, including “shifting growing seasons…and damage to crops and livestock from extreme heat”.
VIOLENCE CONTINUES: A new Global Witness report found that 146 land and environmental defenders were killed or disappeared worldwide in 2024, Dialogue Earth reported. About 82% of those cases occurred in Latin America. Although last year had fewer murders compared to 2023, an author told the outlet that “criminalisation and other types of non-lethal attacks are on the rise”. Folha de São Paulo noted that Colombia topped the world ranking for the third consecutive year with 48 killings. The newspaper added that Indigenous peoples were victims of one-third of the attacks.
SUSTAINABLE COCOA: Increasing the cover of trees providing shade for cocoa plantations to 30% could sequester 307m tonnes of CO2-equivalent in west Africa, according to new research covered by Carbon Brief. That figure is enough to counterbalance current cocoa-related emissions in Ivory Coast and Ghana, the study notes.
COP30 INCOMING: The Brazilian government opened a funding programme worth R$12bn (£1.7bn) for “rural producers and cooperatives affected by climate events” between June 2020 and 2025, ((o))eco reported. Low rainfall in 2023 and 2024 “harmed agricultural production, especially soya beans”, the outlet noted. Elsewhere, InfoAmazonia found that deforestation and agricultural expansion means that only seven countries in the world emit more carbon than the Brazilian Amazon. Bloomberg reported that the “top US diplomat” in Brazil is due to visit COP30 host city Belém this week to discuss “deforestation and organised crime in the region”.
BIG MEAT IS WATCHING: An organisation funded by the US meat and dairy industry has “engaged in intrusive surveillance of animal rights groups”, according to DeSmog. The outlet found that the Animal Agriculture Alliance created a database of 2,400 people “linked to animal welfare and environmental groups” and “shared information with livestock companies about the romantic partners and even biological ties” of people in these groups. The organisation told DeSmog: “The Alliance shares relevant information and resources that are helpful to the food community, but does not seek to influence or direct the actions of any organisation or law enforcement.”
Spotlight
Family food at COP30
This week, Carbon Brief’s food, land and nature reporter, Yanine Quiroz, covers an initiative to serve food from the rainforest at the upcoming COP30 in November in Belém, Brazil.
Quiroz attended a press trip to Belém in September, organised by the Nature Conservancy Brazil, the Climate and Society Institute and Nature4Climate.
On the table sit bowls of cocoa, açaí, jatobá, chicory, Vitória-régia jelly and other foods typical of the Brazilian Amazon.
These foods are just a handful of the many grown in Pará by family farmers, quilombola communities, women and young people, who make up the Bragantina Network.
This network, supported by the civil-society organisation Regenera Institute and philanthropic organisation Climate and Society Institute (iCS), has pushed for a commitment from Brazil that 30% of the food served at COP30 will be sourced from family farming, agroecology and Indigenous peoples.
That would inject at least $3.3m Brazilian reals (£463,000) into family farming in Pará, according to Mauricio Alcântara, co-founder of Regenera Institute. He told Carbon Brief:
“I think this is a great achievement for family farmers.”
Alcântara said that at climate COPs, food is often “very poor and disconnected from the local culture”. The Belém summit aims to showcase the great crop diversity of Brazil’s Amazon and the sustainable practices supported by the federal government, he added.
A history of resistance
A 2024 report from Escholas Institute found that 80% of the food that reaches Belém comes from other states in Brazil, even though Pará is located in the “most biodiverse biome in the world”, Alcântara said.
That is why the Bragantina Network helps agroecological producers in Pará gain access to markets through promoting public policies. One such example is the National School Feeding Programme, which feeds 45 million children on a daily basis, Pedro Zanetti, a specialist in land-use transition, food systems and bioeconomy at iCS, told the press.
The Bragantina Network emerged in the 1990s as a movement aimed at rescuing native Amazonian seeds and products, such as cassava and manioc, that had largely disappeared from agricultural practices and diets, Maria de Nazaré Ghirardi, a family farmer and technical advisor for the Bragantina Network, said.
In Pará, there are 80 cooperatives that employ 8,000 families of farmers, according to a mapping analysis done by Regenera Institute, Frontiers of Development Institute and iCS.
Alcântara told the press:
“When we talk about the COP, in addition to generating income for many producers, it is also about showing that this food has a history. A history of climate action, community resilience, women’s empowerment and traditional communities.”
He also said that after COP30, the Bragantina Network will seek the building of public infrastructure to store the foods produced by family farms to supply the metropolitan region of Pará through public policies and the private market.
Watch, read, listen
‘GOLD RUSH’: A Mongabay video looked at the impact of gold mining on local communities, water quality and forests in the Republic of the Congo.
INDIA ISLAND ISSUES: Time reported on how India’s biodiverse Great Nicobar island is threatened by “mega” development projects put forward by the government.
NEW BLEND: The New York Times examined whether hybrid grape varieties can “solve the climate change dilemma for winemakers”.
AGRI IMPACTS: Journalist Michael Grunwald discussed his new book, “We are eating the Earth: The race to fix our food system” on US late-night talk programme, the Daily Show.
New science
- India’s government-incentivised “zero-budget natural farming” programme more than doubled farmers’ profits, improved “bird biodiversity outcomes” and maintained similar crop yields | Nature Ecology & Evolution
- Annual CO2 emissions from forest and shrub fires in China decreased over 2001-22, but increased for cropland fires, especially in the country’s north-east | Atmospheric Chemistry and Physics
- Watching documentaries can increase public interest in plant-based diets in the US, according to an analysis of search queries linked to six documentaries and consumption data | Nature Food
In the diary
- 24 September: UN special high-level event on climate action | New York
- 26 September: World maritime day
- 29 September: International day of awareness of food loss and waste
- 30 September-1 October: 42nd UN-Water Meeting | Geneva, Switzerland
Cropped is researched and written by Dr Giuliana Viglione, Aruna Chandrasekhar, Daisy Dunne, Orla Dwyer and Yanine Quiroz. Please send tips and feedback to cropped@carbonbrief.org
The post Cropped 24 September 2025: High Seas Treaty milestone; ‘Erratic’ water cycle; Family food at COP30 appeared first on Carbon Brief.
Cropped 24 September 2025: High Seas Treaty milestone; ‘Erratic’ water cycle; Family food at COP30
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 sen