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We handpick and explain the most important stories at the intersection of climate, land, food and nature over the past fortnight.

This is an online version of Carbon Brief’s fortnightly Cropped email newsletter. Subscribe for free here.

Key developments

Roadless rule

ROADLESS RULE NO MORE: The US agriculture department announced last week that it plans to “rescind a decades-old rule that protects 58.5m acres [236,741km2] of national forestland from road construction and timber harvesting”, the Los Angeles Times reported. The “Roadless Rule” has been in place since 2001 and “established lasting protection for specific wilderness areas within the national forests”, the outlet continued. US agriculture secretary Brooke Rollins called the rule “outdated”, while environmental groups “condemned the decision and vowed to take the administration to court”, according to the Washington Post.

PUBLIC LANDS PRESSURE: Amid Republican opposition, Utah senator Mike Lee pulled his “controversial proposal” to sell off public lands for housing developments from the “sprawling” domestic policy bill known as the “Big Beautiful Bill”, the Salt Lake Tribune reported. According to Politico, Lee blamed “misinformation” for the provision’s lack of support, even though, “in reality, he faced stiff opposition from western Republicans from states with large public land holdings”. On Tuesday, the Senate “narrowly approved” the bill, which now has to return to the House – where “many members have balked at the Senate’s changes to the measure” – for further approval, the Washington Post said.

BACK ONLINE: The Famine Early Warning Systems Network (FEWS NET) is back online following a “months-long shutdown” due to the Trump administration’s “slash[ing]” of the US Agency for International Development (USAID) budget, Devex reported. The publication called the site’s restoration a “welcome development for aid agencies around the world” and noted that FEWS NET is “widely regarded as the world’s most reliable early-warning system for food insecurity”. Updated data is “expected to be available by October 2025”, said a spokesperson for FEWS NET.

Bonn to Belém

FOOD-CLIMATE NEXUS: While “agenda fights”, finance and threats to multilateralism dominated the narrative at Bonn climate talks that concluded last week, food discussions were “potentially productive”, observers told Carbon Brief. The meeting featured the first of two workshops under the Sharm-el-Sheikh joint work on climate action, agriculture and food security – the only dedicated forum for agriculture in UN climate talks. Action Aid’s Teresa Anderson told Carbon Brief: “Agriculture negotiations are now reaping the bitter harvest from Baku. After initial resistance, negotiations resulted in more targeted and potentially useful guidance to at least help identify finance gaps in agriculture.”

SECOND CHANCES: A Down to Earth comment by Indian agricultural economist Smita Sirohi described the workshop as “​a “second chance to reframe the debate” around agriculture and climate to ensure more focus on adaptation, not just mitigation. While countries shared their experiences with “systemic and holistic approaches” to integrating climate into national food plans, finance for these approaches was still a sticking point. Anderson added that many governments “[came] to the conclusion that agroecology is the most effective way to achieve multiple climate and development goals”. (For more, read Carbon Brief’s in-depth summary of the meeting.)

ENDS WITHOUT MEANS: Adaptation was at the forefront in Bonn. Before the start of the conference, countries “miraculously” narrowed down a list of “indicators” for the global goal on adaptation (GGA) from 9,000 to 490. Key divisions emerged between developed and developing countries on whether to include indicators on “means of implementation” (MOI) – shorthand for finance – as well as language around “transformational” adaptation. The final text invited experts to continue refining GGA indicators to a manageable 100, it included MOI indicators that developing countries viewed as a win.

FOREST FUND: More countries and private-sector groups supported Brazil’s Tropical Forest Forever Fund during London Climate Action Week, a statement said, but there is currently no funding estimate available ahead of its launch at COP30. Brazil is aiming for “$4-5bn per year for the investment in forests, 20% of that being destined for Indigenous [peoples] and local communities”, the country’s environment and climate minister, Marina Silva, told Carbon Brief at an event last week at the Brazilian embassy in London. Silva added: “It is not donation, it is not charity…We can have a fund that will be remunerating those who protect their forests – be they communities or private owners.” Elsewhere, Brazil and the UN held the first “global ethical stocktake” in London to hear from civil society before COP30.

Spotlight

How extreme weather is impacting India’s ‘food in 10 minutes’ delivery drivers

This week, Cropped’s Mumbai-based reporter Aruna Chandrasekhar spoke to a union leader fighting to hold delivery-app companies accountable for protecting millions of India’s food delivery workers from extreme weather.

Driven by increasing urbanisation, smartphone usage and home-based lifestyles further entrenched by the Covid-19 pandemic, food delivery platforms continue to boom in India.

On any given waterlogged day of the week, Mumbai residents can order iPhone chargers with their okra, or apples from New Zealand, even well after midnight.

But India’s 7.7m delivery workers are having to brave extreme heat and high water in India’s crowded cities – whether on electric mopeds, cycles or horseback – to bring India such items direct to the doorstep.

It begs the question: are food delivery platforms effectively outsourcing climate adaptation to informal gig workers with fewer social protections?

A Nature Cities study published in January found a “significant surge” in lunchtime orders on the hottest days of the year in China’s cities, “reveal[ing] the transfer of heat exposure” from consumers to delivery riders.

Similarly, a study published in Sage last week found that digital technologies are “reshaping food practices in urban India in ways that reinforce existing caste, class and gender hierarchies”.

As temperatures touched 44C this summer, the Telangana state gig and platform workers union (TGPWU) urged citizens to offer a “glass of water” to the thousands of delivery workers battling extreme heat to bring them their food.

According to the International Labour Organisation, delivery workers in India can work up to 82 hours a week, with apps increasingly racing to offer consumers delivery in under 10 minutes.

“Is 10-minute delivery even possible? Can we look at humans as humans and not as robots?” says Shaik Salauddin, TGPWU founder and general secretary of the Indian Federation of App-Based Transport Workers (IFAT), speaking to Carbon Brief. He continues:

“As unions, we can tell workers to rest, but who’s going to pay for their daily bread? But if the aggregators are telling workers to carry hot parcels of biriyani in 46C, bag between their shoulders, wearing a dark uniform: can you imagine the heat and mental stress? And then buildings with 10-15 floors don’t give them access to the lift, when they have less than 10 minutes to deliver.” 

Salauddin, who worked as a taxi driver for 10 years, has been fighting for the impact of extreme weather on food delivery workers to be better recognised. Two weeks ago – well into the monsoon – India’s National Disaster Management issued guidelines to recognise delivery workers “as one of the most vulnerable” to heatwaves and to create separate sections for informal workers in city and state heat action plans.

This week, Salauddin is sending out extreme rain alerts on WhatsApp and Telegram. He tells Carbon Brief that he is “tired of the PR” and “superhero” praise heaped on riders risking their lives in record floods by the same delivery platforms that offer little accountability or transparency. He says:

“I tell workers there’s a red alert for extreme rain, open drains are overflowing, your EVs won’t make it, please don’t go out there. In 10 minutes, the apps say: ‘Please come online, we’ll pay you 30% extra as part of rain mode.’ Who do I fight with now?”

To Salauddin, climate change and “just transition” are “big words” that have to be linked to livelihoods and need a far-reaching vision: whether it is subsidies for marginalised castes to buy or retrofit EVs, more charging stations, or even just restrooms for exhausted workers. Governments must engage with unions every three months, he says, not just at the height of summer or monsoon. With the exception of a few states, India’s many gig workers are not formally recognised for social security benefits.

The biggest change, Salauddin says, must come from food delivery apps themselves. He concludes:

“Simply saying that ‘we’re a broker between companies and people, we take our commission and nothing else’ is not a good model. They need to take responsibility for livelihoods, for climate impacts and their emissions. In our nature of work, we should be looking at the future of work – and the future is already here.”

News and views

COUNTING CONTROVERSY: The European climate commissioner, Wopke Hoekstra, may allow EU member states to “count controversial carbon credits from developing countries towards their climate targets”, the Guardian reported. Hoekstra told the outlet that “developing countries were keen to gain EU financing through carbon credits” and that the “possibility of allowing this was ‘potentially very attractive’”. However, the Guardian noted, “green groups are furious” and insist that the EU must “meet its targets domestically”, without the use of overseas carbon offsets.

FUELLING FOOD: Around 40% of petrochemicals are used by food systems around the world, mostly through synthetic fertilisers and plastic packaging, according to a new report. The research, from the International Panel of Experts on Sustainable Food Systems (IPES-Food), noted that food production and processing accounts for at least 15% of global fossil-fuel use. Action on food systems is “missing” from global agreements to transition away from fossil fuels, the report said. IPES-Food expert, Prof Raj Patel, said in a statement: “Delinking food from fossil fuels has never been more critical to stabilise food prices and ensure people can access food.”

PLANT FUEL: Efforts are underway in Chad to switch to “green charcoal” – a fuel made from plant waste, such as sesame stalks or palm fronds – to prevent further “rampant deforestation”, Agence France-Presse reported. The central African country has lost more than 90% of its forest cover since the 1970s and is “steadily turning to desert”, the newswire said. “Green charcoal” is intended for household uses, such as cooking, as an alternative to cut-down trees. An initiative to produce this fuel, which allegedly emits less CO2 than ordinary charcoal when burned, is backed by the World Bank and the UN refugee agency, added AFP.

G&T DANGER: “Volatile” weather, made “more likely by climate breakdown”, may impact the flavour of juniper berries – the “key botanical” in gin – according to a new study covered by the Guardian. The research, published in the Journal of the Institute of Brewing, looked at berries from seven European countries taken across different harvests. “A wet harvest year can reduce the total volatile compounds in juniper by about 12% compared to a dry year. This has direct implications for the sensory characteristics that make gin taste like gin,” the lead study author Dr Matthew Pauley, an assistant professor at Heriot-Watt University, told the newspaper.

TREE TROUBLE: The UK missed its tree-planting targets by an area of forest equivalent to the size of the Isle of Wight over the past five years, according to Carbon Brief analysis. New figures showed that 15,700 hectares of trees were planted across the UK in the last year – roughly half of the annual 30,000 hectare target set by the previous government. England, Scotland, Wales and Northern Ireland have repeatedly not met national targets since 2020, previous data showed. These missed goals amount to more than 36,000 hectares of unplanted forest.

ASIA IMPACTED: According to the World Meteorological Organisation’s State of Climate in Asia 2024 report released last week, Asia is warming twice as fast as the global average, reported the Times of India. Extreme summer heat and reduced winter snowfall “accelerated glacier mass loss” in 23 of 24 glaciers in the central Himalayas and Tian Shan, Down to Earth wrote, with drought in China affecting more than 4.8 million people. Per the report, marine heatwaves “gripped a record area of the ocean”. The north Bay of Bengal region recorded the “second fastest rate” of sea level rise globally after the South China Sea, wrote the New Indian Express.

Watch, read, listen

BLEACHING POINT: Kenyan marine ecologist Dr David Obura spoke to the Guardian about coral reefs that are “flickering out across the world”.

SHADOWY BROKER: The Financial Times looked at the life and death of Samuele Landi, an Italian “telecoms entrepreneur turned fraudster” and carbon-credits broker.

HORNBILL HOUR: The Some Like it Wild Podcast spoke to Dr Aparajita Datta about her research on the “secret life” of hornbills and valuing community knowledge in conservation research.

WOMEN’S WORK: For LitHub, Dr Sarah Boon wrote about “trailblaz[ing]” women scientists who carried out fieldwork in the 1900s.

New science

  • A new study in Science Advances found that more than half of existing sea turtle hotspots “may disappear by 2050, with many new habitats in high shipping intensity areas” under a high-emissions scenario. “Alarmingly”, the authors added, only 23% of these hotspots are conserved under current marine protected areas. 
  • According to new research in Nature Climate Change, protecting “existing young secondary forests” can remove eight times more carbon per hectare than new tree plantations.
  • A new study, published in Nature and covered by Carbon Brief, found that six staple crops will face “substantial” yield losses under future climate change – even when accounting for farmers’ adaptation efforts.

In the diary

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 2 July 2025: US public lands under attack; How India’s gig workers are suffering under climate change; Bonn to Belém appeared first on Carbon Brief.

Cropped 2 July 2025: US public lands under attack; How India’s gig workers are suffering under climate change; Bonn to Belém

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Climate Change

Pawa in Palau

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This week our powerful Pacific team is in Palau for the Pacific Islands Forum Leaders Meeting. This is a major moment in our campaigns for Pacific climate justice and to stop deep sea mining. So what’s it all about, what can we expect over the coming days, and why is this year’s meeting in particular so important? Read on to find out!

*Pawa is Melanesian word meaning collective power.

Meet Moemoana Schwenke, our Pacific Climate Campaigner

“When you love something deeply, you do everything you can to protect it.”

@greenpeaceap

For us in the Pacific, protecting our home is an expression of love. Follow our journey across the Pacific all the way to COP31 in Türkiye. Pacific voices continue to lead the call for climate justice champion our priorities and build a movement for a Fossil Fuel Free Pacific, from our islands to the world. Join the movement and follow the journey. @Moemoana Schwenke

♬ original sound – Greenpeace Australia Pacific

What is the Pacific Islands Forum (PIF)?

The Pacific Islands Forum, or ‘PIF’, is our region’s most important political organisation. It is where countries of the Pacific — including Australia and New Zealand — come together to collaborate on shared challenges and to set collective goals.

The PIF Leaders Meeting is an annual weeklong event that includes a dedicated meeting of the Pacific’s small island developing states (PSIDS), many special side events organised by Pacific civil society, the leaders’ meeting itself, and more. At the end of the week, leaders issue a Forum Communiqué, capturing what they have agreed on, their shared priorities and the actions they will take together.

This year’s meeting is being held in the beautiful northern Pacific nation of Palau, the same place our Pacific team gathered back in January to plan for the year.

Islands in Palau
© Hector John Periquin

What’s at stake this year?

Climate change has dominated the PIF for decades. Pacific leaders have been crystal clear it is their number one priority, and the annual gathering is the moment they can exert maximum pressure on Australia over its fossil fuel record.

The voyage to COP31

This year’s meeting comes less than three months before COP31, where Australia will take on the role of President of Negotiations — a role it has committed to undertaking in partnership with the Pacific — and less than a month before the ‘Pacific Pre-COP’, to be held in Fiji and Tuvalu.

Following a fraught round of mid-year negotiations in Bonn, PIF leaders will need to set out a clear vision and priorities for COP31. These include accelerating a just global transition away from fossil fuels, defending science as the foundation of international climate cooperation, and increasing the availability and accessibility of finance for renewable energy and climate adaptation.

Pictured left to right - 
- Dr Simon Bradshaw, COP31 Lead and report author, Greenpeace Australia Pacific
-Belyndar Rikimani, Campaigns and Research Lead, Pacific Islands Students Fighting Climate Change
-Shiva Gounden, Head of Pacific, Greenpeace Australia Pacific
© Greenpeace / Marie Jacquemin

Accountability for Australian fossil fuel exports

Since the last PIF Leaders Meeting, Australia has signed the Belém Declaration on the Transition Away from Fossil Fuels. The declaration reaffirmed the legally binding commitment to help limit global warming to 1.5°C and recognised that this is incompatible with new fossil fuel production. Yet, Australia has continued to approve new coal and gas projects, including at least five since the last PIF Leaders Meeting.

Barry Dick observes the community graveyard impacted by coastal erosion on Pele Island in Vanuatu.
© Niki Kuautonga / Greenpeace

What is Greenpeace doing?

We’re going big this year, taking six members of our team to Palau to support Pacific leaders to hold the line, hold Australia accountable, and show the world what’s at stake. We’ll lobby leaders, hold press conferences, share our messages with the world, and support our incredible local partners in Palau.

Members of the Greenpeace Pacific team at the Pacific Islands Forum leaders' meeting in Palau, 2026.

How can you get involved?

PIF is the first in a drumbeat of major moments where we’ll be carrying the voices of the Pacific to the world. Come October we’ll be voyaging to Fiji on our ship Oceania for the Pacific Pre-COP, and in November we’ll be off to Antalya for the world’s climate negotiations (COP31).

Learn more about the Pacific way to a fossil fuel free future by checking out our report and exhibition.

Follow our journey, and check back here for more ways to join the movement for climate justice. Together we have the pawa!

Pawa in Palau

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Climate Change

From firefighting to future-proofing: Preventing wildfires must be the priority

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Gill Einhorn is head of the Forest Future Alliance and Natalie Çilem is community lead of the Global Wildfire Leadership Network.

Wildfires have devastated communities across the world this summer, claiming lives, displacing thousands of people and leaving billions in economic damage in their wake. In Europe alone, wildfires have already caused an estimated €19 billion in losses this year.

They are an economic, financial and public health challenge that is growing faster than many governments and markets are prepared for – and exposing the real costs of poor land management.

A system built for recovery, not resilience

Far more money is currently spent responding to the disastrous effects of wildfires than preventing them in the first place. The United Nations Environment Programme estimates that more than half of wildfire-related spending goes towards response, while planning receives only around 0.2 percent. This problem is not limited to wildfires; over 95 percent of disaster aid between 2005 and 2017 was allocated to response, and less than 4 percent was directed towards prevention or preparedness.

Forests are critical, but without investment in how land is managed and protected, their value is neither stable nor guaranteed. Protecting forests requires investing not only in conservation, but in the conditions that keep forests standing.

    Each dollar invested in wildfire-resistant construction could save around $210 in avoided future economic losses, according to a report by the World Economic Forum and Forest Future Alliance. Despite this evidence that prevention can significantly reduce future costs, wildfire resilience remains chronically underfunded.

    This spending discrepancy is creating significant challenges for insurers, asset owners and financial institutions. Global insured losses from natural catastrophes reached $107 billion in 2025, with wildfires, floods and storms accounting for 92 percent of claims.

    In this context, insurers are reassessing where and how they are willing to underwrite risk. Around 56 percent of global wildfire losses between 2000 and 2023 were uninsured. In some high-risk areas, insurers are scaling back coverage altogether, leaving homeowners, businesses and governments to shoulder a growing share of the costs – making it increasingly difficult to break even.

    Proven solutions are already paying off

    In many regions, wildfires are driven not by natural causes but by the deliberate clearing of land for agriculture. Degraded landscapes are becoming drier, more flammable and increasingly vulnerable to catastrophic loss, creating a vicious cycle of deforestation, economic damage and rising emissions.

    The answer is not simply stronger firefighting capacity. Governments, investors and businesses must work together to shift capital upstream into prevention, resilience and long-term landscape stewardship of healthy forests. That means planting appropriately, investing in heat-resistant species, exploring approaches that minimise fire footprints through active management, and exploring the AI and technology solutions that are burgeoning.

    A burnt olive tree in an area affected by a wildfire in Ano Sichaina near Patras, Greece, August 14, 2025. REUTERS/Louiza Vradi

    A burnt olive tree in an area affected by a wildfire in Ano Sichaina near Patras, Greece, August 14, 2025. REUTERS/Louiza Vradi

    Solutions to this already exist and are proven to have an impact. Following devastating wildfires year-on-year, Portugal shifted its approach to wildfire management, increasing prevention spending within its national rural fire management system from around 20 percent in 2017 to approximately 60 percent in 2022. While many countries remain locked in a reactive cycle of disaster response, public policy can shift investment upstream and make resilience a priority before fires occur.

    Indigenous communities have long used proactive land stewardship to reduce wildfire risk while supporting healthy and productive landscapes. For example, the Cheslatta Carrier Nation in British Columbia traditionally managed fuels through cultural fire practices but now implements mechanised fuel removal methods under commercial agreements. By combining Indigenous stewardship with sustainable forest management, Cheslatta is generating community benefits while also boosting wildfire prevention.

    Resilience can also be strengthened through finance and technology. FireSat, a partnership led by Earth Fire Alliance with Google.org, the Gordon and Betty Moore Foundation and Muon, is a satellite constellation designed for rapid wildfire detection. Scanning every 20 minutes, it can detect fires 400 times smaller than current systems and track them through smoke and darkness in almost real time. In California alone, FireSat could prevent up to 350,000 acres from burning each year. It has recently received significant new investments allowing it to expand towards a constellation of more than 50 satellites that will monitor every point on Earth every 20 minutes or less.

    In Brazil’s Pantanal, the Embrace the Forest initiative uses AI-powered detection towers across 2.5 million hectares to support earlier intervention and faster response. During the severe 2024 fire season, the initiative contributed to a 40 percent reduction in burned area compared to 2020.

    A drone view shows burnt cars following a wildfire in Dymi, near Patras, Greece August 14, 2025. REUTERS/Louiza Vradi

    A drone view shows burnt cars following a wildfire in Dymi, near Patras, Greece August 14, 2025. REUTERS/Louiza Vradi

    These examples illustrate what is possible when resilience is treated as an investment priority rather than a recovery cost. But we must ensure funding for these measures is scaled before disaster strikes. Initiatives like the Global Wildfire Leadership Network (GWLN) are key, bringing together corporate decision-makers, investors, insurers, governments and Indigenous leaders to direct investment towards prevention and align finance, technology and stewardship to protect nature, safeguard communities and strengthen future economic stability. With a goal of doing more together than the sum of our parts, the network focuses on Forest Future Alliance GWLN Solutions Labs – where partners sign up with the intent to collaborate.

    Rewarding prevention

    Financial incentives must be created that reward prevention. This can be done by scaling public-private partnerships, supporting long-term landscape stewardship, investing in community capacity including Indigenous wisdom and technology. Ultimately, our terrestrial natural reserves are critical infrastructure that support resilient economies and thriving communities.

    One in three people are dependent on forest services, goods and economic opportunities for survival, so it’s in all our interests to protect what we have. Forests support cooling, water and food security – and are a very cost-effective way of removing carbon dioxide from the atmosphere, where done appropriately.

    UN chief warns climate crisis “in overdrive” as El Niño threatens to fuel the fire

    No sector can solve this challenge alone. The benefits of wildfire resilience are shared across communities, governments, insurers, investors, utilities and businesses. A single intervention can protect homes and livelihoods, reduce insurance claims, secure water supplies and lower future public costs. Because the benefits are shared, the solutions must be too. Coalitions of actors can take proven approaches further than any one individual or organisation could alone.

    As wildfires continue to burn at an unprecedented scale, the opportunity now is to roll out solutions, shift investment upstream and build a future where resilience, rather than recovery, becomes the foundation of thriving economies.

    The post From firefighting to future-proofing: Preventing wildfires must be the priority appeared first on Climate Home News.

    From firefighting to future-proofing: Preventing wildfires must be the priority

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    Climate Change

    Guest post: Why tough methane cuts are crucial for keeping warming ‘well-below’ 2C

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    Methane is a powerful greenhouse gas and the second-largest contributor to global warming after carbon dioxide (CO2).

    Methane traps heat in the atmosphere more efficiently than CO2, but has a significantly shorter lifespan, fading after just a few decades.

    Therefore, reducing emissions of methane – a gas primarily produced by agriculture, fossil fuels and waste management – is a powerful option for limiting global warming in the near-term.

    Yet climate strategies and models often only focus on CO2, or combine all greenhouse gases into one metric known as “CO2 equivalent”.

    The latter approach makes reducing methane emissions dependent on modelling choices and assumptions about the “equivalence” of methane and CO2.

    It hides the opportunities and challenges linked to methane’s high warming and short lifetime.

    In a new study, published in Communications Earth & Environment, we offer a different perspective that “decouples” CO2 and methane reduction and takes global warming limits as a starting point for determining the required level of methane cuts.

    We show that, even under the most ambitious existing national net-zero targets, an absence of methane reduction leads to peak warming that exceeds 1.85C above pre-industrial levels.

    The study highlights that, to limit peak warming to well-below 2C, net-zero CO2 targets must be complemented by stringent methane emissions cuts.

    CO2 equivalent

    How much methane corresponds to one tonne of CO2?

    The question is as difficult to answer as: ‘how much spaghetti equals a chicken?’ You could compare the two meals according to their calories, protein content or cost. Each metric can be convenient, but is only valid for that specific comparison – no amount of spaghetti is the same as a chicken.

    The same is true for the conversion of emissions of methane and other gases to CO2-equivalent emissions. It can be convenient, as it allows different gases to be compared or combined into a single number. This is why the metric is used in climate targets or evaluating the effectiveness of different mitigation options.

    But, because methane and CO2 have different atmospheric lifetimes and warming properties, any conversion is only valid for a chosen time horizon and a chosen baseline.

    Depending on the assumptions baked into calculations, methane mitigation can either appear as an immediate priority or framed as almost unnecessary.

    There are a number of metrics that scientists use to convert greenhouse gases – whether methane, hydrofluorocarbons or nitrous oxide – into CO2-equivalent emissions:

    • “GWP20” measures how much heat a greenhouse gas traps in the atmosphere over a 20-year period, relative to CO2. It emphasises urgent methane mitigation but has been criticised for its implicit discounting of future damages.
    • “GWP100” looks at a 100-year timeline. It gives more weight to long-term warming and is used in “integrated assessment models” (IAMs) used by scientists, national emission reporting to the UN and by the GHG Protocol used by companies.
    • GWP*” considers the rate of emissions, rather than warming over a fixed time horizon. Under GWP*, very limited methane reductions bring CO2-equivalent emissions to zero, meaning remaining methane emissions can be designated as causing “no additional warming”. (This interpretation remains controversial as it assumes the continuation of historical levels of warming.)

    IAMs are the tools used to generate future emissions scenarios. Because they combine CO2 and methane emissions, the impact of methane emission cuts alone is difficult to isolate in existing emission scenarios.

    IAM-generated scenarios also assume mitigation decisions driven by costs. Combinations of CO2 and methane emission pathways that are not purely cost-effective are, therefore, not represented, even though climate policy is messy and emission pathways are rarely cost-effective in the real world.

    Only a few countries – including Japan, Mexico and South Korea – specify methane mitigation targets.

    A different approach

    In our study, we separate CO2 and methane emissions and treat them as independent.

    Instead of choosing a conversion method, we suggest that states and organisations set a limit on peak global warming first, then, based on their existing net-zero targets, determine the minimum compatible methane reduction target.

    Companies and countries around the world have set net-zero targets focused on CO2, as well as those that include all greenhouse gases. As a result, our research looks at the necessary methane reductions for both types of goal. We consider scenarios where companies or countries deliver linear – in other words, steady – emissions reductions to reach net-zero.

    Using a simple climate model, we systematically combined methane and CO2 (or greenhouse gas) mitigation pathways starting in 2025 and calculated peak warming.

    The figure below shows how peak warming depends on both the year of reaching net-zero CO2 and the level of methane cuts.

    Peak global warming relative to 1850-1900 reached until 2100 (50% likelihood), for combinations of the year of global net-zero CO2 emissions (x-axis) and the change in global methane (CH4) emissions between 2020 and that year (y-axis), assuming linear trajectories. Black lines are contours of equal peak warming. The three bars on the right show independent estimates of where CH4 emissions could or would land on the same vertical scale: CH4 mitigation available at no net cost (IEA, red), the 2030 mitigation potential (Global methane status report, orange), and the current legislation scenario for 2050 (Global methane status report, purple). Adapted from Weber et al. (2026).

    The blue arrows in the figure show that to limit warming to 1.7C under a 2050 net-zero CO2 scenario, methane emissions would need to fall by at least 69% by 2050, relative to 2020.

    Our research also finds that, if an organisation or country’s 2050 net zero-target covers all greenhouse gases, its methane emissions would need to fall by 63% instead.

    However, under current policies, methane emissions are expected to increase by around 20% by 2050, relative to 2020. We find that this pathway would result in peak warming above 2C by 2050 – even if global CO2 emissions were to reach net-zero by that date (see purple bar on the right-hand side of the figure above).

    The figure also shows how, if methane emissions remained at 2020 levels and net-zero CO2 was delivered by 2040 or later, warming would exceed 1.85C. This level of warming is above what has been argued as consistent with the Paris Agreement’s “well-below” 2C limit.

    Conversely, cutting methane emissions by around one-third – in line with the Global Methane Pledge target for 2030 – could reduce peak warming by 0.15C, of which 0.05C could be delivered by interventions that come at no net cost. These are shown by the orange and red bars, respectively, on the figure above.

    The table below highlights the minimum compatible methane cuts for three different peak warming levels and net-zero CO2 or greenhouse-gas emission targets.

    Peak warming Year of net-zero CO2 emissions Year of net-zero greenhouse-gas emissions
    2050 2060 2100 2050 2060 2100
    1.7C -69% -63%
    1.8C -32% -56% -11% -47%
    2C +8% -8% -83% >50% +33% -78%

    Minimum methane emission reductions between 2020 and the year of net-zero emissions, consistent with peak warming of 1.7C, 1.8C, and 2.0C at 50% likelihood, assuming linear emission trajectories. For some net-zero targets and peak warming levels, there are no compatible methane mitigation targets (indicated by “–”).

    Remaining carbon budget

    The global carbon budget refers to the amount of cumulative CO2 emissions allowable while still meeting a particular global warming threshold.

    The 2021 climate science report from the Intergovernmental Panel on Climate Change (IPCC) and a 2023 Nature study estimated that, by 2025, the remaining carbon budget for holding warming to 2C would be around 1,000-1,150bn tonnes of CO2 (GtCO2).

    We find that these estimates are founded on the assumption of methane reductions of 27-35% by 2050, relative to a 2020 baseline. (A 2024 Communications Earth & Environment study reached similar conclusions.)

    Under the GWP* metric, where methane emissions are only cut to maintain “no additional warming”, the remaining carbon budget would be constrained. The best estimate of a 2C budget shrinks by around 30% to approximately 750GtCO2.

    Finally, if methane emissions are not cut at all in the future, our findings suggest that the remaining carbon budget for 1.7C of global warming has, in effect, already been exhausted.

    Our analysis shows how peak warming depends on both CO2 and methane reduction – and how methane-specific targets can help refine existing net-zero targets.

    Crucially, we show that complementing net-zero CO2 targets with stringent methane cuts is necessary to limit peak warming to well-below 2C.

    Weber, K. et al. (2026) Limiting warming by CO2 and methane mitigation in an expanded scenario space, Communications Earth & Environment, doi:10.1038/s43247-026-03832-1

    The post Guest post: Why tough methane cuts are crucial for keeping warming ‘well-below’ 2C appeared first on Carbon Brief.

    Guest post: Why tough methane cuts are crucial for keeping warming ‘well-below’ 2C

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