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An acceleration in human-caused global warming could see the Paris Agreement’s 1.5C limit breached before 2030, a new study suggests.

The paper, published in Geophysical Research Letters, finds that, over the past decade, the planet has been warming at its fastest rate on record.

The authors isolate the trend of human-driven warming in the long-term global temperature record, removing the influence of natural factors, such as El Niño, volcanic eruptions and solar variation.

They find that the world had been warming at a rate of around 0.2C per decade since the 1970s, but has “accelerated” since 2015 to a rate of 0.35C per decade.

The study warns that if the current rate of warming persists, the 1.5C Paris threshold will be breached in the next few years.

“The essential result of this paper isn’t how fast we’re warming, but that warming is now happening faster than before and that the difference isn’t negligible,” an author on the study tells Carbon Brief.

Warming signal

The year 2024 was the hottest on record, with global average temperatures at the surface exceeding 1.5C above pre-industrial levels for the first time.

Crossing the 1.5C threshold in a single year is not equivalent to a breach of the Paris Agreement, which refers to long-term warming – typically interpreted as over a 20-year period.

However, rapidly rising global temperatures are prompting scientists to ask when this internationally recognised threshold might be broken.

Human activity has been the primary driver of rising global temperature in the long term, through greenhouse gas emissions and land-use change. However, natural factors also have warming and cooling effects from year to year.

The study authors identified three main sources of this natural variability.

El Niño and La Niña – collectively referred to as the El Niño-Southern Oscillation (ENSO) – are generally the largest drivers of year-to-year fluctuations in global temperatures. The study authors identify volcanic activity and changes in solar variation as the other two main natural influences on global temperature trends.

Study author Dr Grant Foster, formerly from the consulting firm Tempo Analytics and now retired, describes these sources of natural variability as “random noise” that sits on top of the long-term warming signal. He explains that “the larger the noise, the harder it is to see the real trend”.

To isolate the warming trend, the authors used a statistical technique that they first employed in a 2011 paper to remove the contributions of ENSO, volcanic activity and solar variation from the global temperature record.

The authors carried out this analysis on five separate datasets of global average surface temperature – NASA, NOAA, the Met Office Hadley Centre and University of East Anglia’s HadCRUT5, Berkeley Earth and Copernicus ERA5.

The plots below show the global temperature between 1880 and 2024, relative to pre-industrial temperatures, from the five datasets.

Each plot shows the original warming record (light blue), in which all drivers of warming are included, as well as the adjusted record (dark blue) which excludes the effects of ENSO, volcanoes and solar activity.

Five charts showing that removing 'natural variability' from global temperature data conforms that global warming is accelerating.
Global temperature trends from five datasets, including (light blue) and excluding (dark blue) the effects of El Nino, volcanic activity and solar activity. Source: Foster and Rahmstorf (2026).

Removing the effects of natural variability makes the years 2023 and 2024 slightly cooler, the study notes, but they remain the two warmest years since the beginning of instrumental record.

Acceleration

Record-high temperatures in recent years have led scientists to ask whether global warming is accelerating.

The authors of the new study decided to use two different statistical approaches to test whether they can identify a “statistically significant” acceleration in global warming from the long-term temperature record.

The “noise” from natural drivers of temperature change, such as ENSO, can make it tricky to spot underlying trends. However, Foster tells Carbon Brief that after removing the influence of natural variability, “acceleration is easy to prove statistically – some might even say it becomes obvious”.

Both tests find that warming is accelerating with more than 98% confidence for each of the five datasets. When the same tests were run on the unadjusted data, they failed to reach even 95% confidence, showing the importance of removing natural variability from the warming signal, according to the study authors.

Under the first statistical approach, called a quadratic analysis, the authors applied a single curved trend line to the warming signal.

For the second approach, the authors used a technique to identify the month when the rate of global warming changed noticeably. The different datasets estimated this date to range from February 2013 to February 2014. They then calculated the speed of global warming both before and after these dates.

Global temperatures increased at an average rate of around 0.2C per decade over 1970-2015, according to the study.

In contrast, the authors find that warming rates have increased to 0.34-0.42C per decade, across the five different datasets, since the February 2013-February 2014 period.

The study reveals that the rate of warming observed over the past decade has been higher than any previous decade in the instrumental record.

Foster tells Carbon Brief that “the essential result of this paper isn’t how fast we’re warming, but that warming is now happening faster than before and that the difference isn’t negligible”.

If this warming rate remains constant, the Paris Agreement 1.5C threshold would be breached between 2026 and 2029, the authors find.

(Their approach estimates the 20-year period where the average exceeds 1.5C of warming, and the breach of the limit is taken as the halfway point in this period.)

The table below shows key results for the five different datasets, including estimates for the date that warming started accelerating, the rate of warming and the year that the Paris Agreement will be breached in each.

Data source Date of acceleration Warming rate (C per decade) Year to cross 1.5C
NASA April 2013 0.36 2028
NOAA February 2013 0.36 2028
HadCRUT January 2014 0.34 2029
Berkley February 2014 0.36 2028
ERA5 February 2014 0.42 2026

Results for the five different datasets, including estimates for the date that warming started accelerating, the rate of warming and the year that the Paris Agreement will be breached in each. Source: Foster and Rahmstorf (2026).

‘Statistical significance’

There are “many opinions” among climate scientists about how fast the planet is currently warming, Foster tells Carbon Brief.

For example, a study from Dr James Hansen calculates a warming rate of 0.27C per decade after 2010. Similarly, the latest Indicators of Global Climate Change report estimates warming of 0.27C per decade over 2015-24.

Foster continues:

“But we all agree it’s higher than before. [The] thing is, we couldn’t prove that statistically.”

Foster tells Carbon Brief that in 2024, Dr Claudie Beaulieu – an assistant professor at the University of California – led a study which concluded that “a recent surge in global warming is not detectable yet”.

Beaulieu used the same statistical method as Foster to investigate whether global temperature data shows an acceleration in warming. However, she did not first remove the natural drivers of temperature change, such as ENSO.

(Carbon Brief wrote about Beaulieu’s work in more detail when it was published.)

Foster tells Carbon Brief that the study was “excellent”, adding:

“They found that confirming acceleration was a close call – the data are very suggestive – but not quite ‘statistically significant.’”

Foster explains that after removing the natural influence, the warming trend is clearer, making it easier to find statistically significant warming levels.

Beaulieu praises the new study, explaining that “the fact that the acceleration signal appears consistently across all five independent datasets is reassuring”.

However, she stresses that “the acceleration may prove temporary”.

She says that “continued monitoring over the next several years will be essential to determine whether the accelerated warming rate identified here represents a lasting shift”.

The study authors say that the main limitation of their work is that the method of removing natural variability is “empirically based, but approximate and imperfect”.

Foster says:

“We estimate the impact of things like El Niño by comparing past values of the El Niño index to past temperature changes, hence we don’t need to know the physics behind it, just the numbers. Statistical results like this are only approximate.”

Meanwhile, an acceleration in warming is supported by many other observations of the Earth’s climate.

For example, ocean heat content – the measure of the amount of energy stored in the ocean – is rising year on year. There is also evidence of acceleration in recent years, with the period from 2020 onward seeing the largest year-to-year increases in ocean heat content on record.

In addition, the Earth’s energy imbalance, which measures the difference between incoming solar radiation and outgoing radiation, has also increased in recent years.

The post Pace of global warming has nearly doubled since 2015, reveals study appeared first on Carbon Brief.

Pace of global warming has nearly doubled since 2015, reveals study

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As Prices Soar, EPA Greenlights Higher Ethanol Blends in Gasoline

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The agency typically doesn’t allow smog-creating ethanol blends in the summer but is relaxing that restriction to appease consumers and farmers.

The Trump administration handed farmers and the ethanol industry a win on Wednesday by issuing a waiver that will allow the use of higher corn-based ethanol blends in gas tanks this summer.

As Prices Soar, EPA Greenlights Higher Ethanol Blends in Gasoline

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Ugandan farmers use British court to try to stop oil pipeline

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A group of farmers plans to sue the developers of the East African Crude Oil Pipeline (EACOP) in a British court, claiming the project breaches the Ugandan constitution and climate and environment law.

In a previously unreported letter before action, sent to the developers’ UK-based arm in January, the farmers say they and their livelihoods risk being harmed by climate change which the pipeline will worsen by generating millions of tonnes of greenhouse gas emissions. 

Their law firm, London-based Leigh Day, plans to file a formal claim in the next few months, in which it will ask for construction of the pipeline – which will cost around $5.6 billion to build, spans Uganda and Tanzania and is four-fifths complete – to be halted.

The lawsuit has been crowdfunded by donations from over 40,000 people, coordinated by the Avaaz campaign group, which promote the case as “one final chance to stop one of the worst oil pipelines on the planet”.

    The pipeline is a joint venture led by French company TotalEnergies, with smaller stakes owned by Uganda, Tanzanian and Chinese national oil firms. But it is operated by EACOP Ltd, a company registered to an office in Canary Wharf, the tallest building in London’s financial district. 

    Leigh Day solicitor Joe Snape, who represents the group of farmers, said EACOP highlights how corporations in the Global North are profiting from fossil fuel extraction projects in the Global South which also suffer most from their worsening of climate change.

    Ugandan law tested in UK court

    The group of four farmers accuses EACOP Ltd of breaching their right to a clean and healthy environment under the Ugandan constitution, as well as its legal obligations under Uganda’s National Environment Act and National Climate Change Act.

    Leigh Day solicitor Joe Snape, who represents the farmers, told Climate Home News that Ugandan law has novel clauses allowing people to make environmental claims without having to demonstrate a precise link to their own loss. They just have to show that the action complained of threatens, or is likely to threaten, efforts to reduce emissions or adapt to climate change, he said.

    However, these clauses have not yet been tested in court, so it will be up to British judges, if they accept the case, to interpret how they apply in practice.

    Leigh Day is keen to use the UK’s legal system because it perceives it as more impartial and efficient than that of Uganda, Snape said. A climate lawsuit filed in Uganda more than a decade ago by a group of young people has yet to conclude.

    EACOP has been subject to repeated lawsuits in several countries, none of which have succeeded. A case at the East African Court of Justice, brought by campaign groups against Uganda and Tanzania, was rejected on procedural grounds last November. 

    A separate ongoing lawsuit in TotalEnergies’ home country of France – a refiled version of an earlier failed claim – cannot stop EACOP going ahead, but it does seek damages from TotalEnergies for affected communities. 

    Thousands already displaced

    The pipeline, which will link Uganda’s Lake Albert oil fields to Africa’s east coast in Tanzania, is around 80% completed according to its developers, with first oil exports possible as early as October.

    Thousands of people have already been displaced by the pipeline, with compensation paid and many training schemes – whose quality has been criticised – already completed.

    Despite this progress, the farmers’ legal team say that a court could still stop the pipeline from being completed. Any contractual or compensation issues arising from the stoppage and the billions of dollars of sunk costs would have to be dealt with separately, said Snape.

    Gerald Barekye, a farmer, researcher and campaigner, from the pipeline-affected Hoima district, will be one of the claimants. He said that Ugandan communities were already living with flooding, drought and food insecurity caused by climate change. 

    “Allowing these oil companies to complete the construction of the EACOP pipeline and extract millions of barrels of oil, which will produce millions of tonnes of emissions, will only make this situation in this region worse and deepen our suffering,” he said.

    Agriculture, which makes up a fifth of Uganda’s GDP and employs two-thirds of its population, is likely to be affected by falling yields, rising plant pests and diseases, reduced suitable for crop growing and changes to growing seasons caused by climate change. 

    As well as the climate impacts, they will argue that the pipeline will have a significant impact on local nature and wildlife from possible oil spills, habitat fragmentation, noise pollution and new infrastructure, and poses a threat to major water resources.

    Ugandan activists participate in a demonstration over proposed plans by Total Energies and the Ugandan government to build the East African Crude Oil Pipeline (EACOP), in Kampala, Uganda September 15, 2023. REUTERS/Abubaker Lubowa

    Michel Forst, UN Special Rapporteur on environmental defenders under the Aarhus Convention, has raised further concerns about “serious allegations of persistent and widespread attacks and threats” against environmental defenders in Uganda over the project.

    In 2022, Ugandan police arrested nine activists protesting against EACOP. One protester, Nabuyanda John Solomon, told Climate Home News at the time that police had broken one man’s arm and hit another in the eye with a baton.

    EACOP Limited did not respond to a request for comment.

    The post Ugandan farmers use British court to try to stop oil pipeline appeared first on Climate Home News.

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    How small island states can make renewables the bedrock of resilience

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    Pepukaye Bardouille is the Director of the Bridgetown Initiative and Special Advisor in the Prime Minister’s Office of Barbados. Kerrie Symmonds is Barbados’ Minister of Energy and Business and Senior Minister coordinating Productive Sectors.

    When conflict erupts in one region, consequences can reverberate across the globe. Beyond the tragic human toll, the economic impact is palpable. In 2022, the war in Ukraine illustrated this clearly: fractured supply chains and soaring oil prices sent fuel import bills skyrocketing. And again, today, as oil prices spike amidst conflict in the Middle East, the stakes could not be higher, in particular for Small Island Developing States (SIDS).

    For SIDS, resilience and energy have always been inseparable. When a hurricane hits, power lines fall. When shipments stall, oil dependence becomes a liability. Yet these countries also hold a strategic advantage in the form of abundant wind, sun, waves, and in many cases geothermal resources.

    Harnessed effectively, these can power entire economies cost-effectively. With this in mind, SIDS have set some of the world’s most ambitious climate targets, with several pledging 100% renewable electricity within the next decade or two. And they have made progress: installed renewable capacity across SIDS tripled from 3.3 GW in 2014 to 9.4 GW in 2024.

    But execution and financing still lag well behind ambition – and in the midst of an oil shock, closing that gap isn’t a policy preference for SIDS. It’s a matter of survival.

    Lessons from Barbados

    Barbados offers an example of what a credible pathway looks like. Its 50MW Lamberts and Castle project will be the country’s first utility-scale onshore wind farm and one of the largest in the Caribbean – building on a renewables base that already supplies 16% of power capacity.

    Developed as a public-private partnership, it evolved from a 10MW concept into a utility-scale investment. That journey holds several lessons for other SIDS looking to accelerate their energy transition.

    First, be honest about what is politically palatable and ensure the population shares in the upside. Many SIDS operate state utilities that view private power producers as threats to sovereignty or revenue. But private actors often bring the capital and expertise that large-scale projects require.

    The answer is smart design. Barbados models this well, pairing private generation ownership with structures that ensure national benefit, including opportunities for citizens to invest directly.

      Second, ensure that the financials really work. Small islands face high per-megawatt costs, which logistics compound: transporting and installing large wind turbines can require port reinforcements, specialist cranes, and road widening.

      These numbers rarely appear in headline budgets but can quietly kill a deal. Financing packages must therefore cover not just generation, but storage, grid upgrades, and the full logistics chain. These are too often treated as afterthoughts when they are, in practice, the difference between a project that gets built and one that doesn’t.

      Collaboration required

      Third, development partners must streamline energy transition support without compromising sustainability. Environmental and social studies, bird and bat surveys, community consultations, and grid analyses all take time, and rightly so. But their multiyear development timelines before a tender is issued are incompatible with 2030 or even 2035 energy targets.

      SIDS need simplified processes with upfront permitting clarity, clearer regulatory pathways, and predefined safeguards. Development partners must move from project-by-project structuring to practical, time-sensitive and replicable models that reduce procedural drag while upholding environmental rigor.

      Mia Amor Mottley, Prime Minister of Barbados, addresses the UN Climate Summit 2025, a high-Level special event on Climate Action.

      Mia Amor Mottley, Prime Minister of Barbados, addresses the UN Climate Summit 2025, a high-Level special event on Climate Action.

      Fourth, recognize that land access is critical to national energy security. In land-constrained countries, which most SIDS are, a handful of parcels can determine whether critical capacity is built. In Barbados, we expanded the Lamberts and Castle wind project site from 30MW to 50MW through careful planning and negotiation. These decisions can make or break a project’s financials, so landowners must be partners in the process, not obstacles to it.

      Finally, mandate ‘all of government’ teams with the stamina to deliver. The Lamberts and Castle project advanced because the Ministry of Energy and Business, Barbados National Energy Company, Barbados Light and Power, community stakeholders and International Finance Corporation – the government’s transaction adviser – worked as a unified team.

      Cheaper electricity and greater security

      Energy transition projects need cross-agency partners empowered to make timely decisions, and a shared mission – all cemented by the ability to remove bottlenecks at the highest level. Institutional collaboration is not a nice-to-have, it is the engine of delivery.

      Resilience cannot be outsourced, nor achieved through pledges alone. It must be built: panel by panel, battery by battery, turbine by turbine, grid by grid.

      Building on the progress at Lamberts and Castle, Barbados is exploring the possibility of tripling its wind energy capacity through a public–private partnership model. Importantly, this expansion will not compromise food security. Wind turbines typically occupy less than 5% of the land area, allowing the remaining space to continue supporting agricultural production, another key resilience priority for Barbados.

      In Barbados, new turbines will soon turn in the same trade winds that once powered sugar windmills, this time delivering cheaper electricity, greater economic security, and the ability to meet climate goals on our own terms. By putting renewables at the heart of resilience, SIDS can secure energy independence and lead the world in climate and economic security.

      The post How small island states can make renewables the bedrock of resilience appeared first on Climate Home News.

      How small island states can make renewables the bedrock of resilience

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