FLOODING: Up to 700 people are believed to have been killed by flash floods in Nigeria, reported BBC News. Northern Nigeria has faced “prolonged dry spells worsened by climate change”, followed by “excessive rainfall”, which can cause flash flooding, reported the Associated Press.
FIRES: In Canada, continuing wildfires forced the evacuation of more than 26,000 people, “with heavy smoke choking millions of Canadians and Americans and reaching as far away as Europe”, reported Le Monde. CBC News reported that authorities in the Canadian province of Saskatchewan have been “battling the worst wildfire [the state has] seen in decades”. Scientist Prof Colin Laroque told the broadcaster: “This is classic climate change…This is our new normal.”
DEVASTATION: In northeastern India, at least 48 people have been killed in flash floods, Al Jazeera reported. Meanwhile, in China’s southwestern Yunnan province, heavy rainfall over the weekend triggered “flash floods and mudslides”, damaging roads and disrupting power supplies to around 5,000 people, reported Reuters.
DRILL, BABY, DRILL: The Trump administration in the US announced plans to eliminate Biden-era protections across millions of acres of the Alaskan Arctic, opening the area up for drilling and mining “in some of the last remaining pristine wilderness in the country”, the New York Times reported. According to US energy secretary, Chris Wright, Trump wants to “double the amount of oil coursing through Alaska’s vast pipeline system” and build a “massive natural gas project as its ‘big beautiful twin’”, reported the Associated Press.
‘GOLD STANDARD’: Elsewhere, more than 6,000 scientists and academics signed an open letter opposing a new push by Trump to impose what he called a restoration of “gold standard science” across federal agencies and national laboratories, reported the the New York Times. It explained: “The executive order puts his political appointees in charge of vetting scientific research and gives them the authority to ‘correct scientific information’, control the way it is communicated to the public and the power to ‘discipline’ anyone who violates the way the administration views science.” Meanwhile, CNN reported that “NASA scientists describe ‘absolute sh*tshow’ at agency as Trump budget seeks to dismantle top US climate lab”.
How much global investment in clean-energy technologies, including renewables, nuclear and energy storage, is expected in 2025, according to the International Energy Agency. This is “twice the amount expected for fossil fuels”, reported Reuters.
(For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Monday, Tuesday, Wednesday, Thursday and Friday.)
The UK’s sunniest spring generated a record amount of solar power, according to new Carbon Brief analysis. The data revealed that the nation’s solar sites generated a record 7.6 terawatt hours (TWh) of electricity from January to May 2025. This is 42% higher than the 5.4TWh generated in the same period last year, as well as marking a much larger 160% increase over the past decade, the analysis said. It added: “The solar electricity generated in 2025 to date has avoided the need to import gas costing around £600m, which would have released 6m tonnes of carbon dioxide (MtCO2) when burned.” The Times and BBC News covered the analysis.
This week, Carbon Brief examines a “casual dress” policy that has been “surprisingly effective” at driving emissions savings in Japan.
For many people, the thought of Japan conjures up images of thronging cities, bright lights and smartly dressed “salary-men” unwinding in an “izakaya” (Japanese pub) after a gruelling day at the office.
Every morning, in cities around Japan, some 38 million office workers put on a uniform of suits and ties and make their way to work.
Come summer, however, and the morning commute adopts a laid-back Friday feel. Men’s suit jackets and neckties are replaced by open collars and short sleeves. Venture to the southern island of Okinawa and you might spot a salary-man in a Hawaiian-style “kariyushi” shirt.
This was not always the case. Twenty years ago this month, then-environment minister Yuriko Koike introduced Japan – and the world – to the term “Cool Biz”.
“Cool Biz” – literally Cool Business – is an enduring campaign aimed at reducing energy consumption from air conditioning in the hot summer months when temperatures routinely exceed 30C.
Introduced in 2005, the same year the Kyoto protocol finally “entered into force”, Cool Biz mandated that government office buildings turn down the air conditioning to 28C and encourage employees to cool off by wearing less formal clothing. The campaign was characterised by the pithy slogan: “No jacket, no necktie.”
The impact was near immediate. By official estimates, nearly half a million tonnes of CO2 were saved in the first year of Cool Biz. The following year the savings tripled.
In 2012, the policy was estimated to have saved Japan 2.2 MtCO2 of emissions. (This is equivalent to the emissions of Montenegro that year.)
While temperature regulations were only mandated in government buildings, the impacts of the campaign extended far wider.
Thanks to a widespread publicity campaign – which included a Cool Biz fashion show of Japanese public figures and business leaders – name recognition reached 96% in its first year, according to a survey by the Ministry of Environment.
Uniqlo, Japan’s largest clothes retailer, recorded a 14% sales bump – which it attributed to its range of Cool Biz-appropriate casual workwear. And the Federation of Japanese Necktie Unions petitioned the government, after it forecast a 30% sales slump worth approximately £1bn.
Twenty years on, working in relaxed attire in summer has become “firmly established in Japanese society”, Atsushi Watabe, programme director of sustainable consumption and production at Japan’s Institute for Global Environmental Strategies, told Carbon Brief.
But research into its popularity revealed that concerns about climate change are unlikely to have played a major role in the uptake.
Surveys with members of the public found that Cool Biz had little or no impact on peoples’ reported environmental awareness or commitment, according to Prof Elizabeth Shove, an emeritus professor of sociology at Lancaster University,
Cool Biz’s actual success was a case of “accidental steering” through a combination of social, material and historical factors, said Shove.
Government officials led by example, she said. Japan’s then prime minister Junchiro Koizumi insisted that Cool Biz be worn for cabinet meetings and appeared in interviews in open-collar shirts.
“If the ministers are wearing a tie, their subordinates would feel uneasy about not wearing it,” prime minister Koizumi said at the time. “So the ministers should not wear a tie.”
Turning down the air conditioning in government buildings, likewise, set a standard for other businesses to follow.
Timing also played a role, according to Watabe. Women working in Japanese offices were some of the earliest to support Cool Biz, having been subjected to cooling conventions adapted for male workers, he said, adding:
“Gradually, men who had always considered wearing suits outside as the norm also accepted the change and began to feel its benefits.”
A key lesson is that the success of Cool Biz came from shifting societal norms rather than targeting the behaviour of individuals, said Shove:
“Norms and values don’t just exist – they come from histories of standards, regulations and building research… [Cool Biz] was surprisingly effective by not changing individual behavior, but by just setting a new standard in the government’s own buildings and in industry.”
DRILLED: A new podcast series explored how ”Greenpeace, which was only tangentially involved in the Standing Rock [oil pipeline] protests, has been slapped with a $666m bill for damages”.
REPUBLICANS ‘SCARED’: The Guardian interviewed former Democratic presidential candidate Bernie Sanders on a wide range of issues, including his thoughts on why some Republicans are “scared” to speak about the reality of climate change.
SELLING NEGATIVE EMISSIONS: A feature in the Financial Times examined the “battle to create a carbon trading market for negative emissions” in the UK.
DeBriefed is edited by Daisy Dunne. Please send any tips or feedback to debriefed@carbonbrief.org.
This is an online version of Carbon Brief’s weekly DeBriefed email newsletter. Subscribe for free here.
This complex undertaking is often characterised by “non-linearity” and “feedback loops”, where small changes can go on to have disproportionately large impacts and where seemingly straightforward paths encounter unexpected roadblocks.
Interventions can be self-amplifying – leading to runaway change, or they can be self-defeating – when progress seems impossible to attain.
Our new policy brief sheds light on these intricate dynamics, which can be overlooked when governments use analytical frameworks based on standard economic thinking.
The brief sets out the most common archetypes of system change and behaviour, as well as the underlying feedback loops that drive them, with the aim of helping policymakers to understand the recurring patterns that can either accelerate or impede progress.
Governments that can recognise these patterns – as well as the ways they can be harnessed or sidestepped – are likely to be better equipped to manage structural change.
This article delves into three key examples from the policy brief, exploring how they are influencing the energy transition and what lessons can be drawn for effective policymaking.
At the heart of the energy transition lies a powerful engine: the reinforcing feedback loops inherent in the development and diffusion of many clean-energy technologies.
This virtuous cycle operates through several mechanisms.
First, “learning by doing”, which means that as more units of a technology, such as solar panels or wind turbines, are produced and deployed, manufacturers and developers become more efficient, processes are refined and costs fall.
Second, economies of scale kick in: as production volumes increase, unit costs decrease due to efficiencies in manufacturing and more developed supply chains.
Finally, wider deployment can trigger network effects and the emergence of complementary innovations. This means that as the adoption of a given technology grows, it can foster an ecosystem of supporting infrastructure, skilled labour and supporting technologies, which can further boost its attractiveness and viability.
Together, these three elements create a powerful reinforcing loop: initial investment drives innovation and cost reduction, which spurs increased demand, attracting further investment.
Solar photovoltaics (PV) and wind turbines are prime examples of this dynamic.
The astonishing growth of solar offers a particularly vivid illustration of the way in which reinforcing feedback loops can blindside experts and policymakers alike.
Solar growth has far exceeded projections made in the early 2000s. Indeed, the world’s actual installed capacity in 2020 was over 700 gigawatts (GW), more than ten times the level expected in outlooks published in 2006, as shown in the figure below.
Global solar deployment has exceeded expectations due to disparate trends and drivers in individual markets that, together, all point in the same direction. China, for instance, met its 2030 target for wind and solar capacity six years ahead of schedule in 2024.
Batteries are also riding this wave, with costs plummeting by around 85% over the past decade as deployment, particularly in road transport, scales up.
However, not all clean-energy technologies benefit from this self-amplifying pattern.
Nuclear power and hydropower, for example, have historically not shown the same rapid cost declines, due to their large, complex and site-specific nature. This contrasts with the smaller, modular and replicable characteristics of technologies, such as solar PV.
This does not negate the potential role of such technologies, but it does mean that they are less likely to see disruptive, exponential and self-reinforcing growth.
There are a number of potential conclusions for policymakers.
Early in the transition, interventions such as feed-in tariffs and public procurement were crucial in kick-starting these reinforcing feedbacks for solar and wind.
As these technologies mature and become cost-competitive, the focus shifts to removing other barriers, such as streamlining permitting processes, investing in grid expansion and reforming markets so they are better able to integrate variable renewable output.
These same principles could now be applied to newly emergent clean-energy technologies. Policies that directly nurture these reinforcing loops, such as deployment subsidies and clean technology mandates, can be expected to be most effective in the initial stages.
Turning again to the example of solar energy, while such initial efforts appeared to be expensive, they paid off over time by unlocking future cost reductions and, thus, kick-starting the self-amplifying feedback loops that are now driving further progress.
This contrasts with the idea that carbon pricing is necessarily the most efficient policy for decarbonisation. It may well be helpful, but as it will not drive rapid early technology adoption, it is less likely to have a self-amplifying effect in the initial stages of the transition.
While the growth of renewable energy is the driving force of the energy transition, another system dynamic, termed “renewable cannibalisation“, can act as a dampening feedback loop. This can potentially slow progress long before full decarbonisation is achieved
This cannibalisation process results in variable renewable energy (VRE) sources, such as solar and wind, receiving decreasing prices for the electricity they generate.
Essentially, the more solar and wind capacity that is connected to the grid, the more they undermine their own revenue. This happens through three main channels.
First, the merit order effect, whereby solar and wind, which have very low operating costs, push more expensive fossil-fuel generators out of the market when supply is abundant.
In markets with marginal pricing, this leads to lower wholesale electricity prices during periods of high renewable output. While this cuts prices for consumers – at least in the short term – these lower prices also reduce revenues for renewable generators, potentially undermining the economic case for further investment.
For example, in California, solar power unit revenues fell by $1.30 per megawatt hour (MWh) for each percentage point increase in solar penetration between 2013 and 2017.
Second, price volatility, where uncertainty over future trends in the generation mix and the balance between supply and demand can make long-term revenues difficult to predict.
This increased uncertainty can raise the cost of capital for new renewable projects, again acting as a brake on investment
The UK, for example, experienced this before the introduction of “contracts for difference” (CfDs), which helped stabilise revenue expectations for renewable developers.
Third, volume risk, where rising VRE capacity increases the likelihood of more frequent curtailment – periods when renewable generation exceeds demand or grid capacity, forcing generators to scale back output and lose potential revenue.
Curtailment in itself is nothing new, but the scale and frequency is changing. Recent analysis by University College London suggests that without significant flexibility or storage, UK renewable generation could exceed demand for more than 50% of the time by 2030.
The analysis found that installed wind and solar capacity is set to surge beyond current levels of electricity demand, as illustrated in the figure below, finding that this could “deter investment” in new projects if no action is taken to address the problem.
These dampening feedback loops illustrate a classic “limits to success” scenario. The very success of renewables, if unmanaged, can create conditions that hinder their continued expansion.
The policy implications here are nuanced. One solution is CfDs, which offer renewable generators a fixed price and have been effective in many countries at mitigating the merit order effect and price volatility, thus maintaining investment.
However, as VRE penetration becomes very high and surplus generation becomes a regular occurrence, other solutions are likely to be needed. This is because existing CfD designs often include clauses that stop payments when market prices drop below zero.
As a result, alternative CfD designs, guaranteeing revenues based on installed capacity or potential – rather than actual – electricity generation might be considered, for example, even though these have other drawbacks.
More fundamentally, our research suggests the solution to this challenge lies in fostering the co-evolution of renewables with technologies such as energy storage and green hydrogen production. These can absorb surplus generation and turn a problem into an opportunity.
Whereas, traditionally, it might be assumed that the market on its own can optimally allocate risk, research suggests that a redesign of market structures may be needed to enable investment and fully realise the cost-saving opportunities of the new technologies.
This is one of several sets of feedbacks discussed in a separate new report published today, looking at the power sector transition in China.
The energy transition is not a series of isolated changes in different sectors. Instead, it is an interconnected system, where progress in one area can catalyse shifts elsewhere. Shared technologies can create reinforcing feedbacks that accelerate decarbonisation across multiple fronts, generating cross-sector synergies.
The relationship between clean power and transport electrification is a powerful example of this. As batteries are deployed at scale in electric vehicles (EVs), their costs fall, enabling ever-wider deployment and further cost declines, as shown in the chart below.
This is due to the learning-by-doing and economies-of-scale feedbacks discussed above.
This cost reduction then makes batteries more viable for grid-scale energy storage, which, in tur, helps integrate more low-cost VRE into the power system.
Cheaper, cleaner electricity then further incentivises the electrification of transport, as well as heating and light industry. This increased electrification boosts demand for renewable power, driving further deployment and cost reductions in solar and wind. It also expands the potential for demand-side response, where consumers adjust their electricity use to help balance the grid.
A similar dynamic is anticipated for “green” hydrogen. As deployment in one anchor sector – perhaps fertilisers or refining – drives down the cost of electrolysers, it makes green hydrogen more competitive for other applications, such as shipping or even long-duration energy storage in the power sector.
Each sector’s adoption of green hydrogen contributes to the shared learning and cost reduction, benefiting all.
The policy implications of these cross-sector synergies could be significant. Their existence suggests, for example, that there is no need to wait for decarbonisation of the power sector to advance further, before beginning the electrification of transport, heating or industry.
This is in contrast to the argument that transport should only be electrified after cutting power sector emissions, since increased EV charging will drive up demand for gas- or coal-fired generation.
While there will be a marginal increase in emissions from plugging a new EV into the power grid, the insights described in our brief imply that it is still likely to be more effective to pursue the transition away from fossil fuels in multiple sectors in parallel, because it can activate beneficial cross-sector feedback loops that are greater than the sum of their parts.
As such, our research suggests that policymakers hoping to take advantage of cross-sector synergies could aim to deliberately strengthen technological linkages between different parts of the energy system. Examples include electricity tariffs and market structures that reward “smart” EV charging and vehicle-to-grid (V2G) services, encouraging industrial participation in demand-side response and promoting integrated home energy systems. These interactions can amplify the benefits of early investment in the transition.
Archetypes such as the self-reinforcing growth of clean technologies, the potential for renewable cannibalisation, the accelerating power of cross-sector synergies and seven others described in our new report paint a picture of a transition that is far from linear. Instead, we find that it is governed by complex interdependencies and feedback loops.
Consequently, our research suggests that policymakers will be much better equipped to manage and steer the transition, if they adopt a systems thinking approach.
Recognising these recurring patterns allows for the design of more robust and effective policies that anticipate challenges and leverage opportunities.
For instance, understanding the power of reinforcing feedback loops in technology diffusion underscores the value of early-stage support for nascent clean-energy technologies.
Conversely, anticipating the dampening effects of renewable cannibalisation highlights the likely benefits of combining renewable buildout with evolving market designs and strategic investments in flexibility solutions, such as storage and demand-side response.
Policymakers that understand and work with these dynamics are likely to be in a better position to spark self-amplifying changes – achieving maximum value for minimum effort – and to avoid self-defeating interventions that go nowhere.
The figures, revealed in new Carbon Brief analysis, show that the nation’s solar sites have generated a record 7.6 terawatt hours (TWh) of electricity during January to May 2025.
This is some 42% higher than the 5.4TWh generated in the same period last year, as well as marking a much larger 160% increase in the past decade.
Solar hit a new half-hourly record of 13.2 gigawatts (GW) on 6 April and, for the first time, accounted for more than 10% of monthly electricity generation in two consecutive months (April and May).
The solar electricity generated in 2025 to date has avoided the need to import gas costing around £600m, which would have released 6m tonnes of carbon dioxide (MtCO2) when burned.
However, solar was still only the UK’s sixth-largest source of electricity in 2025 to date, after gas (37TWh), wind (33TWh), imports (18TWh), nuclear (15TWh) and biomass (8.0TWh).
Although this year’s solar high was partly driven by the record sunniest spring, it was also aided by rising capacity, which reached 20.2GW in 2024, up by 2.3GW from 17.9GW a year earlier.
Solar capacity is set to reach at least 45GW by 2030 as part of the government’s ambition to decarbonise the power sector and become a “clean-energy superpower”.
(This article refers to the UK throughout, but the electricity generation data only covers the island of Great Britain. Northern Ireland is part of the all-Ireland electricity system.)
The leap in solar output in 2025 saw generation reaching a record 7.6TWh in the first five months of the year, up 42% year-on-year.
Electricity output from UK solar installations saw particularly big jumps in March – where the 2,320 megawatts (MW) average was up 66% from a year earlier – and in April (3,189MW, up 53%).
There was a more modest 37% year-on-year increase in May 2025 – the country’s second-sunniest May on record – with average output reaching a new monthly high of 3,383MW.
The amount of electricity generated from solar also hit a new high of 2.5TWh in May 2025, beating April 2025’s 2.3TWh into second place. The previous record of 2.1TWh was set in June 2024.
The figure below shows the average monthly output of the UK’s solar capacity, in MW. Output dips in the short, dark days of winter and generally peaks with the longer daylight hours in June.
(The differences between installed electricity generating capacity, actual power output at any given moment and the amount of electricity generated per hour/day/month/year can cause confusion. The UK’s installed solar capacity reached 20GW at the end of last year. This is the maximum amount of power that could theoretically be produced at one time. In practice, the maximum power output recorded to date is 13GW and the average across a full month reached just over 3GW in May, generating 2.5TWh of electricity.)
The electricity generated by the UK’s solar panels in the first five months of 2025 – at 7.5TWh – is enough to have offset the need for around 16TWh of imported gas.
Buying this gas would have cost around £600m – based on recent average wholesale prices – and burning it would have resulted in roughly 6MtCO2, adding nearly 2% to total UK emissions.
The 16TWh of avoided gas imports is equivalent to 10% of the UK’s net gas imports in the same period last year – or around 10 individual Q-Max liquified natural gas (LNG) tankers, the largest currently available.
(For comparison, the UK only took 24 LNG deliveries during April to September 2024, according to data provider Argus. Figures for the first five months of last year are not available.)
The total amount of electricity generated by solar determines how many deliveries of imported gas can be avoided each month, as well as how far the power sector can cut its emissions.
In total, solar accounted for 11.6% of UK electricity generation in May 2025, only the fourth time it has ever breached the 10% threshold, after June 2023, June 2024 and April 2025.
(Solar topped 10% of monthly global electricity generation for the first time in April this year.)
However, the impact on the electricity market depends more closely on the hour-to-hour and day-to-day variations in solar generation due to the weather, seasons and diurnal cycles.
The highest UK solar output on record was reached at 13:00 on 6 April, when the technology was delivering 13.2GW of power and meeting 40% of demand for that half-hour period.
The UK saw 653 hours of sunshine in the period from 1 March to 31 May 2025, making it the sunniest spring since records began in 1910, according to the Met Office.
This total is 43% higher than the average for 1961-90. Before this year, the previous record for the sunniest spring had been set in 2020, when there were 626 sunshine hours.
UK sunshine hours have been on an increasing trend, particularly since the 1980s, according to Met Office analysis for Carbon Brief and illustrated in the chart below, which does not cover 2025.
The analysis found that, on average, spring months had been around 15% sunnier over the past decade than during the reference period from 1961-90.
(The analysis put this trend down to a combination of natural variability, changing circulation patterns and possible human influence from shifts in aerosol pollution.)
In a statement announcing the sunniest spring, Met Office scientist Emily Carlisle said: “Seven of the top ten sunniest springs on record for the UK since 1910 have occurred since the year 2000.”
A further Met Office release notes that spring 2025 is not only the sunniest spring on record, but also the fourth-sunniest season overall, with only three summers having had more sunshine.
The extra sunshine this spring contributed to unusually high solar power output per unit of installed capacity, a metric known as the “capacity factor” of the UK’s solar plants.
The capacity factor is a percentage, showing the actual electricity generation relative to the maximum theoretical output, if the panels were working at full capacity all of the time.
While sunny weather helped drive the new highs for solar this spring, the UK’s growing capacity also contributed to the records.
After stagnating at around 12-14GW for several years after the then-Conservative government’s decision to end subsidies for solar in 2015, the UK’s installed capacity has since leapt to 20.2GW as of the end of 2024.
Capacity has grown as prices have fallen – boosting the economic case for solar – and as projects with newer “contracts for difference” have started to get built.
Early 2025 has seen the strongest start to the year since 2012 in terms of new rooftop solar capacity. Moreover, the UK is expected to add 3-3.5GW of new solar capacity across 2025 as a whole, according to Solar Media Market Research, up from the 2.3GW added in 2024.
Since taking office last July, energy secretary Ed Miliband has approved around 3GW of new solar capacity at giant sites, including the 500MW Heckington Fen and 500MW Gate Burton schemes.
The government is targeting 45-47GW of solar by 2030 as part of its “mission” to become a “clean-energy superpower”, which aims to have low-carbon sources meeting 100% of UK electricity demand and at least 95% of generation in the country.
Before then, the National Energy System Operator (NESO) is aiming to run the electricity system without fossil fuels for a short period, at some point this year.
Since setting itself this target in 2019, NESO has been making preparations by contracting for zero-carbon sources of grid stability services. These include “inertia” and voltage control, which have traditionally only been offered by conventional fossil-fuel generators.
Only familiar to grid engineers, previously, these terms have recently seen widespread usage in media coverage and finger-pointing over April’s blackouts in Spain and Portugal.
The increase in electricity generation from variable sources, such as wind and solar, brings new technical and market-related challenges, including increasing periods of “negative pricing”.
However, the solutions to these challenges are well-known and already being implemented in the UK. These include the buildout of battery storage systems, increasing interconnector capacity linking the national grid to other countries and new sources of grid stability, such as flywheels.
This is an online version of Carbon Brief’s fortnightly Cropped email newsletter. Subscribe for free here.
LIVESTOCK EMISSIONS: Climate scientists speaking to the Financial Times accused the governments of New Zealand and Ireland of using an “accounting trick” to “cover up” methane emissions from their livestock sectors. An open letter from 26 climate scientists and covered by the newspaper said that New Zealand’s “proposed new methane targets risk setting a dangerous precedent”. The title added that scientists have separately raised concerns about Ireland’s approach.
POTENTIAL PROBLEMS: The controversy hinges on a way for measuring the impact of methane emissions on climate change, called “global warming potential star” (GWP*), the FT said. This method “estimates [methane’s] contribution to warming based on how emissions are changing relative to a baseline”. By contrast, the “long-established approach” used by most countries “compares the total warming impact of a given mass of methane to the same mass of [carbon dioxide] over a 100-year period”, the newspaper said.
‘MISAPPLICATION’: The scientists told the FT that some governments are “misapplying” GWP* to justify setting “no additional warming” targets, which allow methane emissions to remain flat rather than decline. The governments of Ireland and New Zealand did not respond to the newspaper’s requests for comment. But the newspaper added that “proponents” of the GWP* typically argue that it “better reflects methane’s short-lived nature in the atmosphere compared to the long-lasting effects of CO2”. One of the scientists behind the letter explained more of his thoughts in a LinkedIn post. A scientist not involved in the letter also posted a response.
SOMETHING FISHY: Elsewhere, an investigation by DeSmog and the Guardian has alleged that several UK supermarkets have sold seabass linked to “devastating overfishing” in Senegal. The two publications said that the retailers are accused of selling fish from Turkish farms that import large quantities of “fishmeal” – ground up fish used as feed – sourced from the African nation. Overfishing for fishmeal in Senegal is linked to “unemployment” and “food insecurity”, according to the Guardian. Responding to the claims, several of the supermarkets said they do not currently source from the implicated farms, but declined to say whether they had in the past.
EARLY MONSOON MAYHEM: An “unprecedented” early monsoon caught India’s farmers off guard, with “massive crop losses in states such as Tamil Nadu, Maharashtra, Telangana and Gujarat”, IndiaSpend reported. Climate scientists attributed the pre-monsoon thunderstorms to “unusual sea surface temperature patterns in the Pacific since 2023” and a higher frequency of “western disturbances” – extratropical storms originating over the Mediterranean. In the past week, north-eastern India has been battered by flash floods and landslides, with “at least 32 people killed and tens of thousands displaced”, the Independent reported. The newspaper noted that “studies show the monsoon in south Asia is getting worse due to the climate crisis”.
DELUGE AND DROUGHT: BBC News reported that more than 700 people are believed to be dead after “devastating” floods hit Nigeria, with the farming region of Mokwa witnessing “the worst [floods] in the area for 60 years”. Separately, Reuters reported that China’s south-western Yunnan province was hit by “flash floods and mudslides”, triggered by heavy rainfall. In unconnected reporting, Bloomberg said that China had stepped up cloud seeding to “bolster rainfall across parched wheat-growing areas” in the north, adding that the country had ramped up “weather modification” investments as “climate change heightens food security risks.”
CANADA BURNS: Canada’s prairie provinces continued to reel from “record-breaking” early-season wildfires, the Guardian reported. It pointed out that in Manitoba alone, wildfires have burned “about 200,000 hectares already this year” – three times “the recent full-year average”. Manitoba premier Wab Kinew said that simultaneous fires “in every region” were a “sign of a changing climate that we are going to have to adapt to”. The Guardian added that First Nations peoples in Saskatchewan – one of three recognised Indigenous peoples in Canada – “have been particularly affected, with some entire communities evacuated”.
In this Spotlight, Carbon Brief speaks to the UK’s former lead UN negotiator about the successes and challenges of international nature talks.
Will Lockhart OBE represented the UK in UN nature negotiations from 2021 until the end of COP16 talks in Rome in February of this year.
In 2022, he helped to negotiate the Kunming-Montreal Global Biodiversity Framework (GBF), a landmark deal which has a headline “mission” to “halt and reverse” nature loss by 2030.
Following his departure from government, he spoke to Carbon Brief about his highs and lows, whether the world is making progress towards meeting its biodiversity goals and the role of UN summits – called COPs – in tackling environmental issues.
Carbon Brief: When you look back at your time heading up biodiversity negotiations, what are your highlights?
Will Lockhart: It’s all still emotionally raw. From a global perspective, the agreement of the GBF was a huge personal highlight. That was a really, really complicated negotiation. The notion that you could have frontpage news that was about an international agreement on nature, that was immensely exciting.
CB: In your view, is it possible to achieve the GBF’s mission to halt and reverse biodiversity loss by 2030?
WL: The trajectory right now would suggest, no, it’s looking incredibly hard to achieve. But, even then, with exactly the right interventions at exactly the right scale, it might still be possible. A fair question might be was it ever possible?…There has always been a contested evidence base about whether it could ever have been achieved.
The important thing is that people spent a lot of time thinking about why we were setting certain kinds of targets…We wanted them to be specific, measurable and achieveable. What does achievable mean? What does ambitious mean? What message are we trying to send? This is politics, this isn’t necessarily science.
If the answer is that it was never possible in the first place, then the question is: ‘Why did the world agree to it?’ And the answer to that is: ‘Because it matters that we try.’
CB: Could there be a better way for countries to address biodiversity loss than the current system?
WL: It’s a very complicated question. A question that everyone has to bear in mind is: ‘What [is the] value [of] the COPs?’ You pour a huge amount of time and resource into a global dialogue, which results in a very, very carefully negotiated outcome. It’s extremely important, in my view, that you have a space where the whole world can come together in a room and agree that it wants to do something. The question is, where does the world locate that process?
I worry that the world is simultaneously asking too much and too little of COPs. It’s asking too much in the sense that there’s so much coverage and intense scrutiny of ‘this person’s arrived’, ‘this comma has moved’…There’s an extraordinary media circus. [There is] extreme expectation on each individual meeting.
And, at the same time, it’s simultaneously asking too little of them. It’s like: ‘Great, this word was in so it was a good COP’ or ‘this word was out so it was a bad COP’. And of course COPs are just one tiny part of this huge global process that needs to happen if we’re going to tackle these problems. I rather worry – and I know that colleagues feel the same – they’re just viewed as ends in themselves.
This interview has been edited for clarity and length. A longer article has been published on Carbon Brief’s website.
RECORD FOREST LOSS: Tropical forest loss hit its highest level in a two-decade record in 2024 – double the level of 2023 – according to satellite data from Global Forest Watch covered by New Scientist. The report authors “attributed the surge in forest loss to the El Niño weather phenomenon and the warming global climate, which made the rainforest a tinderbox”, the magazine said. Climate Home News added that the rate of forest loss was the equivalent of losing 18 football pitches every minute.
RATIFY THIS: The EU ratified the UN “High Seas Treaty” last Wednesday, “joining a global effort to protect the ocean, curb environmental damage, tackle climate change and preserve biodiversity”, Jurist News reported. The EU’s ratification of the landmark treaty was joined by six of its member states: Cyprus, Finland, Hungary, Latvia, Portugal and Slovenia. The EU also pledged €40m as part of a Global Ocean Programme to support African, Caribbean and Pacific countries, according to an EU Commission press release.
THOUSAND CUTS: A “cornerstone” ecological research programme could potentially be culled by the Trump administration, the New York Times reported. Abolishing the Ecosystems Mission Area (EMA) “was an explicit goal of Project 2025, the blueprint for shrinking the federal government”, the story added. However, the budget cut “still needs to be approved by Congress”, with scientists rallying to save the EMA, the paper wrote. On Monday, the Trump administration announced plans to “eliminate federal protections across millions of acres of Alaskan wilderness” that could open the region to drilling and mining, according to another New York Times story.
NET NATURE LOSS?: In the UK, the Guardian reported that the “nature-friendly farming budget is set to be slashed” for “all but a few farms” in an upcoming spending review. Meanwhile, legal analysis of the Labour government’s new planning and infrastructure bill showed that “more than 5,000 of England’s most sensitive, rare and protected natural habitats are at high risk of being destroyed by development”, per another Guardian story. A key concern for green groups, it added, is a “cash for trash” clause that allows developers to “inflict adverse effects on the integrity of a protected site” if they pay into a fund to restore nature elsewhere.
MIRAGE CITY: Reuters reported on Egypt’s plans to build a new desert city, 42km west of Cairo, that could reroute “about 7% of [its] annual Nile River quota” from fertile delta land. According to the story, an estimated 10m cubic metres of Nile water will flow daily to Jirian city to “pass by upscale glass-fronted housing units and eventually” irrigate a 2.28m acre “New Delta” agricultural project. Jirian city will include luxury housing, a free economic zone and even a “yacht marina”, the newswire added, noting that the country is facing “mounting water shortages, power constraints and deepening economic crisis”.
FOREST-FRIENDLY BATTERIES: Electric car batteries made using iron and phosphorus “that pose less of a threat to forests” are “rapidly replacing batteries reliant on cobalt and nickel”, according to an International Energy Agency (IEA) report covered by Climate Home News. From 2020 to 2024, the market share of lithium nickel manganese cobalt batteries has risen from one-tenth to almost half, according to the IEA data. Both cobalt and nickel are “mainly mined in rainforest countries”, such as the Democratic Republic of the Congo and Indonesia, the publication added.
REFORESTED SCHOOLS: Mongabay explored how “urban forests” in schools in Niger are helping to build “climate resilience and education”.
SO LONG, SALGADO: The New Yorker examined the visual legacy of photojournalist Sebastião Salgado, who died last week. Salgado’s Genesis series is celebrated as a “paean to natural landscapes and Indigenous ways of living”.
SECOND ACT: In an Atlantic long-read, writer Emma Marris looked at the debate calling for a law to protect ecosystems along with endangered species in the US.
PROUD, NATURALLY: CBC News reviewed Animal Pride, a new documentary about queer animal behaviour that filmmaker Connel Bradwell described as “nature’s coming-out story”.
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
Will Lockhart OBE represented the UK in UN nature negotiations from 2021 until the end of COP16 talks in Rome in February of this year.
He tells Carbon Brief that the agreement of the Kunming-Montreal Global Biodiversity Framework (GBF) in Canada in 2022 was a “huge personal highlight” that made nature “frontpage news”.
But when asked about whether it is possible to reverse the rapid decline of biodiversity in just five years – the headline “mission” of the GBF, commonly referred to as the “Paris Agreement for nature” – he says:
“The trajectory right now would suggest, no, it’s looking incredibly hard to achieve. But…with exactly the right interventions at exactly the right scale, it might still be possible.
“A fair question might be was it ever possible?…There has always been a contested evidence base about whether it could ever have been achieved.”
Shortly after the GBF was agreed in 2022, Carbon Brief spoke to a range of biologists who expressed doubt that it would be possible to totally reverse the decline of nature over such a timescale.
Earlier this year, Carbon Brief and the Guardian published an investigation finding that more than half of countries who have submitted plans to the UN failed to commit to protecting 30% of their territories for nature – one of the key levers for reversing biodiversity loss.
Countries have never fully met any target to help nature since the UN biodiversity convention was established in the 1990s.
The world’s biodiversity is declining at a faster rate than at any other time in recorded history. Around one million animal and plant species already face extinction.
The GBF is a global agreement with an aim to “halt and reverse biodiversity loss” by 2030 and achieve “harmony with nature” by 2050.
To help achieve its aims, the GBF sets out 23 targets for countries covering a wide range of topics, from protecting and restoring ecosystems to slashing subsidies for activities harmful to nature and providing funding to developing countries.
The GBF follows the Aichi targets, the previous set of UN goals for tackling nature loss by 2020 that ended in collective failure.
Towards the end of the 2010s – as it became clear that the Aichi targets were likely to fail – a flurry of research papers were published examining what it would take to “bend the curve” on biodiversity loss.
Among the most influential was a 2018 commentary in Nature Sustainability, led by the late pioneering biodiversity scientist Prof Georgina Mace. It urged countries to “clearly specify the goal for biodiversity recovery” in their post-2020 agreement for nature, “analogous to the [UN climate change] 1.5-2C target”.
On biodiversity loss, Mace and her team wrote:
“This declining trend must not only be halted, but also reversed.”
The post-2020 agreement for nature – covering the decade from 2021 to 2030 – was meant to be finalised in 2020. However, the Covid-19 pandemic caused the COP15 biodiversity summit to be postponed several times, before it was eventually held in two parts, starting in October 2021 and concluding in December 2022.
When negotiators met in Montreal to decide the details of their post-2020 agreement, the idea of halting and reversing biodiversity loss within a few years was already viewed as a steep challenge, Lockhart says:
“The important thing is that people spent a lot of time thinking about why we were setting certain kinds of targets…We wanted them to be specific, measurable and achieveable. What does achievable mean? What does ambitious mean? What message are we trying to send? This is politics; this isn’t necessarily science.
“If the answer is that it was never possible in the first place, then the question is: ‘Why did the world agree to it?’ And the answer to that is: ‘Because it matters that we try.’”
When Carbon Brief spoke to biologists about the feasibility of the goal in 2023, they expressed similar sentiments.
Dr David Obura, founding director of Coastal Oceans Research and Development, Indian Ocean (CORDIO) East Africa and current chair of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), told Carbon Brief in 2023:
“As a scientist, whether we can achieve halting and reversing by 2030, I’m highly doubtful.
“[But] for a political document like this, there has to be a time-bound [element]. So, in that sense, I think halt and reverse by 2030 is the right language to have, for sure.”
But whether setting a lofty target truly spurred sufficient action on biodiversity loss remains an open question.
Following on from the agreement of the GBF in 2022, countries were asked to submit new national plans for how they will meet its goal. These are known as national biodiversity strategies and action plans (NBSAPs).
In October 2024, Carbon Brief and the Guardian reported jointly that 85% of nations had missed the deadline for submitting their NBSAPs.
As of June 2025, only 26% of parties have submitted new NBSAPs. (Separately, 67% of parties have submitted shorter – and less detailed – national targets.)
Further Carbon Brief and Guardian reporting found that, of countries that have submitted nature plans, more than half do not commit to protecting 30% of their territories for nature by 2030, which was billed as one of the headline targets of the GBF.
And research published in Nature Ecology and Evolution found that countries that have submitted nature plans have broadly failed to commit to another GBF target to restore 30% of degraded ecosystems by 2030.
Following on from a set of fractious UN environmental negotiations last year, some experts have called for “reforms” to the way that these summits – known as COPs – work.
Lockhart tells Carbon Brief that, following his time representing the UK at the highest level at COPs, he still carries hope for the future of these summits. But, he says, he also has questions about how the world views the role of these negotiations in addressing environmental problems:
“A question that everyone has to bear in mind is: ‘What [is the] value the [of] COPs?’
“You pour a huge amount of time and resource into a global dialogue, which results in a very, very carefully negotiated outcome. It’s extremely important, in my view, that you have a space where the whole world can come together in a room and agree that it wants to do something.
“The question is, where does the world locate that process?”
He said that he fears the “world is simultaneously asking too much and too little of COPs”, continuing:
“It’s asking too much in the sense that there’s so much coverage and intense scrutiny of ‘this person’s arrived’, ‘this comma has moved’…There’s an extraordinary media circus. [There is] extreme expectation on each individual meeting.
“And, at the same time, it’s simultaneously asking too little of them. It’s like: ‘Great, this word was in so it was a good COP’, or ‘this word was out so it was a bad COP’. And, of course, COPs are just one tiny part of this huge global process that needs to happen if we’re going to tackle these problems. I rather worry – and I know that colleagues feel the same – they’re just viewed as ends in themselves.”
COPs were “always” meant to be just one “part of the jigsaw puzzle”, he adds:
“We agree stuff. It doesn’t get delivered, by and large. It doesn’t get delivered because the implementation processes aren’t in place back at home in different government departments.
“The reasons that the implementation processes aren’t in place varies based on political factors, capability factors, jurisdictional factors, all sorts of different things. The problem is that by focussing on COPs as an end to themselves, we risk missing the wood for the trees.”
Lockhart is now working as the director of climate and energy at Apolitical, an online platform offering training and support for governments globally.
Carbon Brief的最新分析显示，2025年第一季度，中国的碳排放量同比下降了1.6%，过去12个月则下降了1%。
新增风电、太阳能和核电的装机容量所带来的出力，足以应对电力需求激增，从而削减燃煤发电量；而此前的排放下降则主要被归因于经济增长放缓。
这项基于官方数据和商业数据的分析显示，中国的碳排放量一年多来一直保持稳定或下降。
不过，该排放量仅比最近的峰值低1%，这意味着只要出现短期反弹，中国的碳排放就可能创下新高。
其他主要发现包括：
如果这种因清洁能源增长而带来的电力行业碳排放下降趋势得以延续，可能预示着Carbon Brief此前在分析中预测的结构性排放下降的开始。
电力行业碳排放下降的趋势很可能在2025年继续。
然而，未来的走势在很大程度上将取决于中国即将于明年公布的下一份五年规划中所设定的清洁能源与减排目标，以及中国对特朗普政府敌对贸易政策的应对策略。
过去十年来，尽管中国化石燃料和水泥行业的碳排放量有高低起伏，但总体上升了20%。
最新数据显示，该排放量可能已经接近达峰以及趋稳，甚至正步入结构性下降的阶段。
截至2025年第一季度的最新数据显示，中国的碳排放量已经连续一年多呈现稳定或下降趋势，如下图所示。
不过，由于该排放量仅比最近的峰值低1%，这意味着其仍有可能在短期内反弹并创下新高。
因此，中国未来的碳排放走向尚未确定，这取决于各经济部门的趋势，以及中国对特朗普关税政策的应对方式。
2025年第一季度中国碳排放的下降主要源于电力行业排放下降了5.8%。尽管整体电力需求增长了2.5%，但火电（主要是燃煤和燃气发电）却减少了4.7%。
由于大量新建风电、太阳能和核电装机投入运行，发电量的增长足以弥补需求的增长。水电发电量也有所上升，虽然其受季节因素影响，但同样对化石能源的替代发挥了作用。
电力行业碳排放降幅超过化石能源发电量降幅，因为生物质和天然气的占比上升，同时燃煤电厂的平均能效也有所提升。
具体而言，燃煤电厂度电煤耗平均下降了0.9%。
下图底部显示了第一季度电力行业煤炭使用造成的碳排放量减少情况，该数据低于其他行业的碳排放量变化。
而在电力行业之外，碳排放量增长了3.5%，其中以金属和化工行业的煤炭使用增幅最大。
煤制化工产业正在快速扩张，背后的推动力包括对进口油气依赖的担忧。2025年第一季度，由于煤价走低而油价偏高，该产业的经济性更具吸引力。
粗钢产量同比增长了0.6%，金属制品增长6%，有色金属产量增长2%。这些增长主要集中在3月份，企业赶在关税生效前集中出口，带动金属需求激增，而高产出一直持续到4月。
房地产开工量同比下降24%，新房销售下降3%，反映出建筑行业对水泥、钢材和玻璃的需求持续疲软。
相比之下，汽车和机械制造的经济产出分别增长了12%和13%，表明对金属的需求正在上升。
水泥产量同比下降1.4%，降幅低于往年，可能是由于气温偏高使得依赖天气的施工活动提前启动。
由于燃气发电装机容量增长14%，尽管燃气发电的平均利用率下降，但电力行业的天然气消费量估计增长了6%。但在其他行业，天然气消费减少，总体上抵消了电力行业天然气需求量的增长。
石油制品消费略有上升，如图中最上方所示。由于天气偏暖，依赖天气的施工和农业活动与往年相比提前开工。
然而，从结构性角度来看，汽车电动化和货运行业改用液化天然气，预示着石油需求将持续走低。
在2025年第一季度排放量同比下降1.6%之际，中国的碳排放自2024年3月以来已连续一年多保持平稳或下降态势。
然而，截至2025年3月底的12个月内，排放量仅比近期峰值下降了1%，这意味着只要出现短期反弹，排放量就可能再创新高。
继一季度大幅下降后，电力行业过去12个月的排放量同比也出现下滑。
在过去40年里，这种情况曾经发生过四次——分别是在2009年、2012年、2015年和2022年。但此次下降首次主要得益于清洁能源发电的增长。
2025年一季度清洁能源发电增速不仅超过整体用电需求增长，也高于过去15年电力需求的平均增长，如上图虚线所示。
此外，过去六个月水电发电量同比保持稳定，这意味着这轮清洁能源的增长是由太阳能、风能和核电装机容量的增长所推动的，而非水电的逐年波动所致。
除发电行业外，2024年12月到2025年3月期间，各行业碳排放均有所下降，但煤化工是个例外。
要使中国整体碳排放量达峰并开始下降，各下降行业的减排总量需超过仍在增长行业的排放增量。
电力和化工以外的煤炭使用量与水泥行业同时达峰，但此后一直在反弹，目前已接近之前的峰值水平。
中国煤炭工业协会预计，钢铁和建材行业的煤炭使用量将下降，而化工行业的煤炭消费量将继续增长。
对煤炭未来需求增长的预期主要集中在化工行业，这也代表着煤炭从单纯的燃料向燃料和原料双重角色的转变。
该协会还认为，燃煤发电将至少在短期内恢复增长，但他们已将2025年的预测下调，与2024年底的展望相比有所保守。
“关税战”可能影响了预期。有分析指出，如果中国GDP因关税下降0.5到1个百分点，可能导致主要用于发电站的燃煤需求也出现类似的下降。
疫情后经济反弹到2024年3月结束，石油产品的消费量自此下降，较峰值减少了2%。尽管化工和航空领域的需求在上升，但由于交通运输领域电气化趋势增强，预计其长期仍呈下降趋势。
天然气的使用量近几个月有所下降，但总体趋势仍可能保持上升。
下表列出了每个行业在12 个月周期内的最高排放量，以及自最新峰值以来的减排量。
除了水泥生产之外，其他行业目前还不能明确判断是否已达排放峰值。然而，有迹象表明，其他行业的峰值也可能已经过去。
诚然，对于石油产品消费和钢铁生产而言，行业预测表明未来排放趋势可能会下降。
对于电力行业而言，只要新增清洁能源装机容量维持在当前或更高水平，就有望带来结构性的排放峰值——因为清洁能源的增长足以覆盖新增的电力需求。
这些行业碳排放量合计占全国八成以上。若这些行业均进入结构性下降阶段，那么中国碳排放总量很可能将开启持续下降通道。
特朗普政府实施的史无前例的贸易关税政策，以及中国的反制措施，将影响今年及未来中国的经济和碳排放前景。
关税措施实施后，首当其冲的是中国沿海出口大省的工厂减产，从而导致排放下降，同时也可能波及投资和消费支出。
但因双方随后达成90天休战协议，反而刺激美国订单短期内激增，以弥补短暂的贸易放缓，并在休战结束前囤积商品。
中国对关税的反应主要集中在通过刺激措施抵消其经济影响。
虽然暂时的休战会降低出台刺激政策的紧迫性，但当前美国对中国的平均关税税率仍高达40%，远高于特朗普上台前的水平，因此中国领导层也很可能在为未来再次加征关税做好准备。
中国的重点将是为那些原本出口至美国的产品开拓国内市场。这一转向或将助力中国实现长期以来所希望推动的经济向消费驱动型增长转型，而成功实现经济再平衡，有望带来更低能耗的经济增长。
中国的应对措施还包括加大对“新质生产力”的重视，该概念强调新兴科技的发展。
这一概念涵盖了清洁能源产业，该产业如今已成为中国经济的重要引擎，因此难以在刺激计划中被忽视。
中国发改委最新公布的低碳示范项目清单，明确了清洁能源投资的重点方向。绿氢、储能、“虚拟电厂”以及基于氢能的工业脱碳是新的增长领域。
从碳排放角度来看，中国对特朗普关税的反应最关键的问题在于：针对这些优先领域（包括新兴的低碳领域及其他清洁能源产业）的刺激措施，是否足够有力。
中国碳排放面临的另一个不确定性来源，是即将于今年6月生效的新可再生能源电力电价政策。
新政策取消了与煤电价格挂钩的价格保障机制，要求新的风电和太阳能发电项目与购电方直接签订电力合同。这可能导致新建风电和太阳能发电项目的售电价格下降。
不过，政策也为满足中央政府能源目标所需的新增装机容量提供了更有利的价格机制——“差价结算”。
该政策的直接影响可能是大量项目争相在6月前完成投产，以确保能够按现行政策享有机制电价。
其效果已经体现在最新数据中：仅 3 月份中国就增加了 23 吉瓦 (GW) 的太阳能和13GW的风能，比该月之前的新增太阳能和新增风能的最高记录高出80%和110%。
下图根据不同的预测显示，预计2025年和2026年新增清洁能源发电量仍将高于去年创纪录的水平。
然而，这一政策也带来了更大的不确定性。一些行业，尤其是分布式光伏，将经历上半年装机量的激增而下半年放缓的艰难时期。
不确定性主要集中在两个方面。首先是地方如何执行这一政策，因为省级政府拥有相当大的回旋余地。考虑到清洁能源对许多省份经济的重要性，预计地方政府会力求以尽量不扰乱行业的方式来落实政策。
第二个不确定性来自中央政府的能源目标。新电价政策将更优惠的价格与中央政府的能源目标挂钩。而在过去几年中，清洁能源增长远远超过了官方设定的目标。
这凸显了即将出台的“十四五”规划中能源目标的关键作用。国家能源局设定的目标是“年均新增2亿千瓦（200吉瓦）以上新能源的合理消纳利用”，这一数字远低于去年实际新增的360吉瓦。
当然，电价政策的最终效果也取决于市场环境。当前中国煤电项目仍在快速上马，存在产能过剩风险。
中国风电光伏发展面临的不确定性，也对该国履行《巴黎协定》下的国际气候承诺带来影响。
2020-2023年碳强度（即单位经济产出的排放量）下降进度明显滞后，中国已经明显偏离实现其2030年碳强度承诺的路径，几乎可以肯定将无法实现2025年的阶段性目标。2024年中国的碳强度下降了3.4%，未达到实现2025年和2030年目标所需的改善速度。
2025年政府工作计划中并未设定碳强度目标，仅包含单位国内生产总值能耗降幅超过3%（不包括原材料消耗）的目标。
这可以间接反映碳强度的改善幅度。2024年，中国的碳强度下降了3.4%，而化石能源使用强度下降了3.8%。如果2025年两者之间的比例相似，那么碳强度可能只能下降大约2.5%。在这种情况下，如果GDP增长达到5%的目标，碳排放量仍可能上升超过2%。
政府工作计划中没有设定碳强度目标，也没有特别强调碳强度的下降，显示出当局当前并未将实现这一目标作为优先事项。
政府工作报告中强调了“双碳”目标，即在2030年前实现碳达峰、2060年前实现碳中和。
然而，按照这些目标，2030年前碳排放仍可继续增长。这意味着到该年度，绝对排放量可能在2024年的水平上大幅增加。因此，即便“双碳”目标得以实现，也不能确保中国当前最核心的国际气候承诺——2030年碳强度目标——能够兑现。
即便今年碳排放有所下降，未来五年也需要大幅加快碳强度改善步伐，才能兑现中国2030年《巴黎协定》承诺。
如果中国仍然致力于兑现2030年承诺，那么该过程就需要体现在下一个五年规划设定的目标中。
过去12个月可能标志着中国二氧化碳排放的一个重要转折点：清洁能源的增长首次超过电力需求增长，并在电力领域取代了化石燃料的使用。
尽管新的电价政策带来了一定的不确定性，但预计2025年仍将迎来创纪录的清洁能源新增装机容量，这表明这种趋势将在今年持续。
中国碳排放的未来长期走势将在很大程度上取决于即将出台的五年规划中设定的目标，以及北京应对美国关税和其他经济压力所采取的政策。
从短期看，美国加征关税将抑制能源需求增长和排放水平。为抵消特朗普关税影响而制定的经济政策，很可能会进一步推动清洁能源产业的发展，并可能促使经济重心转向国内消费，这意味着能源消费的增长将相对于GDP增长更少。
但另一方面，中国此前的经济刺激措施往往伴随着排放的急剧上升。中国若想转向消费和新技术驱动的刺激政策，而非高碳排的基建重工业，就必须突破传统发展模式。
电力行业的排放是否已经达峰，将取决于清洁能源供应增长与总体电力需求增长之间的竞赛。
按行业来看，除了电力行业，建筑材料、钢铁以及石油制品消费等领域的排放也可能已经达峰。
这些行业合计占中国与化石燃料相关碳排放的80%以上。然而，在所有这些行业中，都存在短期反弹的可能和不确定性。
目前仍有较大排放增长潜力的行业是煤化工。美国加征关税后国际油价的下跌将削弱该行业的盈利能力，可能导致即便新增产能增加，其工厂利用率也将下降。中国对自美国进口石化产品征收的报复性关税本可能本可能使煤化工行业受益，但这些关税据报已被豁免。
总体而言，这些因素可能推动中国未来五年排放持续下降，并有望在未来五年内实现大幅绝对减排。
然而，若政策出现转向，也同样可能导致碳排放在通往2030年的过程中继续上升。
Shenzhen, a city of nearly 18 million people bordering Hong Kong, is known for pioneering China’s economic reforms 40 years ago.
Now, it is taking carbon mitigation measures ahead of others and acts as a “pilot” for the construction of “low-carbon cities” in China.
It is the first Chinese city that has replaced all of its buses, taxis and ride-hailing cars with electric versions, while about 77% of all new cars sold in Shenzhen were NEVs in 2024 – significantly higher than the national rate of 48%.
It has also introduced a carbon emissions cap – in support of switching from the “dual control of energy” to “dual control of carbon” – ahead of the announcement of a national cap.
In addition, the Shenzhen local emissions trading system (ETS) and “green bonds” were both rolled out before the national ETS and national “green” bonds.
Despite taking steps early, some scholars tell Carbon Brief that Shenzhen’s efforts – which the local government calls the “Shenzhen model” – will be tricky to reproduce for city-level low-carbon transitions elsewhere in China.
Carbon Brief looks back at Shenzhen’s low-carbon transition efforts to date and assesses its progress on carbon mitigation.
Shenzhen’s low-carbon transition did not happen overnight – it resulted from early planning, government support and market-driven solutions, Wei Fulei, director of finance, taxation, trade and the industrial development research centre at the China Development Institute (CDI), a state-sponsored thinktank based in Shenzhen, tells Carbon Brief.
The city’s low-carbon transformation kicked off in the 2000s, when the number of days with heavy air pollution peaked in Shenzhen.
A BBC News report back in 2017 said that after a decade’s work on tackling pollution, Shenzhen “reduced its average air pollution by around 50%”.
The move was largely a result of changing its “industrial base”, which made Shenzhen “one of [the] first batch of these ‘low-carbon cities’”, said the BBC News article.
During this period, the officials developed strategies for “low-carbon development”. Part of this included nourishing the growth of a number of “strategic emerging industries”, such as the “information and communications technology“, which in return provided core technology support for low-carbon industries, largely benefiting the NEV sector.
The current leading global electric vehicle (EV) giant, BYD, for example, was born in Shenzhen against this background.
“With this ‘industry gene’, Shenzhen only needs to adapt and upgrade accordingly to meet the new demands of the NEV industry [in the 2020s],” says Wei.
According to the Shenzhen government work report at the 2025 “two sessions”, the city – whose population makes up 1% of the country’s total – produced 22% of China’s NEVs in 2024.
About 100 new “climate investment and financing projects” will be launched in the year ahead, said the report, adding that another 180bn yuan ($24bn) of “green loans” will be also be issued.
Shen Xinyi, analyst and China team lead at the Centre for Research on Energy and Clean Air (CREA), tells Carbon Brief that the local government has a track record of nurturing new industries:
“Wind and solar power, along with EVs, were all emerging industries that required substantial investment and technological research 20 years ago…The risk of failure was high, but the Shenzhen government introduced innovative policies to support them.”
The quick growth of NEV companies has pushed up the share of NEVs in the local vehicle market. On top of national subsidies, the local government has also provided support for producing and purchasing NEVs.
In 2024, NEVs accounted for some 77% of new car sales in Shenzhen, significantly higher than the national share of 48%.
In addition, the city has also replaced all of its buses, taxis and ride-hailing cars with electric versions – the first city to have done so in China.
Heran Zheng, lecturer in sustainable infrastructure economics and finance at University College London (UCL), tells Carbon Brief that the “greener transport fleet” speeds up Shenzhen’s low-carbon transition, because a city’s low-carbon transition mainly requires two focuses – “transport transition” and “industry decarbonisation”.
Zheng says:
“There are limited policy efforts a city can make in carbon mitigation. It can work on greener transports. London, for example, set up the Ultra Low Emission Zone to encourage the usage of public transport and cleaner vehicles. And a city can upgrade industries and mitigate their emissions, which are harder to do because no city wants to slow down economic growth.”
Shenzhen, “different from some coal mining cities in China”, has an “advantage” in industry transition, says Zheng, which allows it to set “more ambitious” emissions targets.
China uses energy intensity and carbon intensity – the energy use and emissions per unit of gross domestic product (GDP) – as key metrics in its climate policies.
In addition, the country has been using the “dual control of energy” system – regulating energy intensity and energy consumption – since 2016. However, it announced plans to switch to the “dual control of carbon” in 2024.
Under the new system, a binding cap for total carbon dioxide (CO2) emissions will be set and will become the main target after 2030, while carbon intensity – the prime target before 2030 – will be gradually lowered to be the secondary target.
(Read more about the “dual control” systems in this edition of China Briefing.)
Here too, Shenzhen was an early mover. As early as 2023, it became China’s “first city to explicitly state its commitment to the ‘dual control [of carbon]’ system”, according to Dialogue Earth.
It issued two “implementation plans” towards this effort, published in 2023, as well as developing a city-level carbon emissions cap.
The plans, compared to the national ones, have more ambitious timelines. A city-level “dual control of carbon” system will be built up by 2025 and it will be “fully implemented” in 2026-30. One of the plans says:
“We will strive to achieve the goal of using a dual carbon emission control approach to carry out quota allocation in the Shenzhen carbon market [for the] manufacturing industry by 2028…and strive to achieve a significant improvement in market regulation capabilities by 2030.”
Shenzhen plans to reduce its energy intensity by 14.5% before the end of 2025, compared to 2020 levels. The national energy intensity target is 13.5% during the same period.
Zheng says that Shenzhen’s commitment “should be within its capacity”, adding:
“There are three major carbon mitigation areas [for China as a whole] – steel, cement and electricity. Shenzhen has no major steel and cement industries, so it only needs to largely focus on electricity…It is also not at the upstream of a supply chain, unlike some fossil fuel cities; it doesn’t need to worry about business, such as coal mining. Its industry structure is dominated by ‘high value-added’ industries, such as technology and NEVs, whose emissions are easier to mitigate.
“In addition, the city is a technology hub. A lot of high-emissions manufacturers have moved out of Shenzhen to its neighbouring cities, such as Shanwei. This is what we call ‘emissions outsourcing’. Shenzhen, benefiting from this, has fewer hurdles in [its] green transition.”
Last year, Zheng and colleagues published a study on this outsourcing of emissions between Chinese cities in Nature. They found that “some cities benefit from the carbon mitigation efforts of other cities more than their own” and suggested that policymakers work to acknowledge these effects.
Another “big difference” between Shenzhen and other cities is that “Shenzhen has its own nuclear power”, says Zheng, which is “important” for the city’s electricity transition – the remaining sector that Shenzhen needs to put efforts towards low-carbon transition.
According to a 2021 report, Shenzhen’s “largest local power source” is the Daya Bay nuclear power station, with a total installed capacity of 6.1 gigawatts (GW).
Nuclear power accounted for 35% of the city’s total power generation in 2021.
It has also pushed up Shenzhen’s low-carbon energy usage – about 47% of Shenzhen’s primary energy consumption was from clean energy in 2024.
Nuclear dwarfs all the other clean energy sources feeding into the city’s grid. The Shenzhen local authority’s 2025 government work report says current solar power capacity stands at about 1GW – and it does not mention wind capacity.
Its “14th five-year plan for climate change response” says that Shenzhen’s renewable energy capacity has “little room” for future growth due to “scarce” energy resources and “limited” land for wind and solar power.
Meanwhile, Shenzhen relies heavily on imported electricity, which accounts for approximately 70% of the city’s total electricity consumption.
This reliance limits Shenzhen’s control over emissions from the sector. It also challenges the local grid’s ability to manage demand during peak usage times.
In 2024, China approved the constructions of more nuclear reactors in Shenzhen’s neighbouring city of Huizhou.
The Shenzhen government also aims to “raise the combined share of natural gas, nuclear and renewable energy to 90% in 2025, up from the current figure of 77%, which is noticeably ahead of the nationwide figure of 52%”, according to a research paper in 2022.
Zheng says that “Shenzhen is a lot like its neighbour Hong Kong, whose energy transition does not rely on solar and wind build up either”.
He adds that in order to achieve a sustainable energy transition, both Shenzhen and Hong Kong would need to utilise their advantage as “financial cities”.
Shenzhen has long been using “market forces” and has successfully “struck a balance between government support and market-driven solutions”, where enterprises “take the lead, handling 90% of the work”, while the government intervenes only when necessary, says Wei.
With little interference from the government, Shenzhen was one of the first seven cities and provinces in China that established a local “pilot” ETS in 2013, ahead of the national rollout in 2021.
Similar to China’s national scheme, the local ETS allocates emissions allowances for companies to trade on the market, based on their emissions intensity – the emissions per unit of output – rather than absolute emissions.
The Shenzhen local ETS covered 38% of the city’s carbon emissions upon launching. The figure rose to 50% in 2020 and will continue to expand, says a report by the trading forum International Carbon Action Partnership (ICPA), with a shift to an “absolute cap” for carbon emissions being announced to apply from 2027.
(For now, the national ETS does not include a cap on emissions either, although this is also set to change.)
However, Yan Qin, carbon analyst at consultancy firm ClearBlue Markets, tells Carbon Brief that despite Shenzhen ETS plans to expand its coverage, more pilot ETS are seeing their coverage “shrinking” due to enterprises leaving to join the national ETS”.
ICPA’s research also finds that electricity production was excluded from the Shenzhen ETS after 2019 when it “transitioned to the China national ETS”.
Yan says that the pilot ETS, nevertheless, “has been an important testing field, paving the way for the successful launch of national ETS eventually. [It] will continue to exist and cover the small to medium enterprises as well as sectors outside national ETS”.
The Shenzhen local ETS, as of 2022, covers water, gas, heat, manufacturing, transport and other sectors, says ICPA.
It was the biggest local ETS in China as of 2024 and maintains the highest annual trading volumes in the country for several consecutive years, says Shenzhen Business News.
In the meantime, Shenzhen has taken initiatives in “green finance”, bringing private investments into the market.
In 2021, Shenzhen issued China’s first overseas sales of “green government bonds” in Hong Kong along with China’s first local “green finance legislation”, which provides a “solid institutional guarantee” for regulating the “green market”, according to an assessment of the legislation by research institute the International Institute of Green Finance.
In contrast, China’s national sovereign bonds were only available to international buyers from April 2025.
Various other “green finance” products have also been issued. According to state-run newspaper Economic Daily, about 4.6 trillion yuan ($633bn) was traded for new energy, NEVs and other environment-related stocks at the Shanghai and Shenzhen Stock Exchange in the first half of 2024.
Nevertheless, Zheng says that the impact of the “green bonds” is “hard to evaluate”. He says: “A lot of projects, such as sewage treatment, can also fall into the category of ‘green bonds’”.
According to the state broadcaster CCTV, Shenzhen’s “green bonds” issued in 2021 covered projects including “construction of ordinary public high schools, urban rail transit and water management”.
Zheng says that although these projects are linked to energy efficiency improvements, they nonetheless make only “limited contributions” to cutting carbon emissions.
Zheng adds that market guidance is “necessary” in a city’s low-carbon transition, but “there is not yet a study on how large a green finance product can make a difference on mitigation”.
Shen says there is nevertheless an important role for “financial instruments” to support the low-carbon transition. She explains:
“Low-carbon industries generally have higher costs than fossil fuel-based industries…With policy support and financial instruments, the costs can be reduced, allowing these industries to scale up.”
The local government and media outlets have touted the city’s achievements on climate as the “Shenzhen model”, implying that it could be applied elsewhere.
Xu Hua, an official from the Shenzhen Municipal Ecology and Environment Bureau, said the model “demonstrated the results to the world” at last year’s COP29:
“Firstly, Shenzhen has continuously improved its top-level design…establishing a comprehensive policy system. Secondly, the city has focused on the transformation and upgrading of key sectors…promoting strategic emerging industries such as new energy, energy conservation, and environmental protection. Thirdly, following the principle of openness…Shenzhen has been exploring new paths for green and low-carbon development.”
Xu added that the city “positions itself as a leader in green development nationwide”, as it had “significantly reduced its energy consumption, water usage and carbon emissions per 10,000 yuan of GDP to one-third, one-eighth and one-fifth of the national average, respectively” by the end of 2023.
However, not all of Shenzhen’s journey is “replicable”, says Shen, adding: “Shenzhen capitalised on the opportunities of its era.” She tells Carbon Brief:
“For example, its supply chain advantages and the skilled workforce that has settled in the city have been key enablers of its high-end manufacturing sector.”
Zheng agrees with Shen, saying that Shenzhen can only represent a certain type of city in China. He says:
“Shenzhen is China’s Silicon Valley and heavily invests in high-end technology. It can only represent a [certain] type of cities in China, the ‘top tier’, such as Beijing, Shanghai and Guangzhou. There are more than 300 cities in China, all facing unique transition situations. It is meaningless for coal-heavy industrial cities to learn from Shenzhen.”
Other cities in China, meanwhile, have also started to explore their own ways to achieve sustainable development.
The city of Suzhou has built the Suzhou Industrial Park – one of China’s first pilot low-carbon industrial parks. It has also established a “market-based carbon inclusion trading system”, which incentivises “voluntary” carbon emission trading among citizens, as well as small- and medium-sized companies.
Meanwhile, the city of Tianjin has launched a collaboration with Singapore to “explore a path for China’s urban systems to reduce carbon emissions”, according to a Xinhua report.
Other cities must “adapt strategies according to their unique conditions”, Shen adds. This sentiment is reflected in a 2023 document issued by China’s State Council – the country’s central government. The document, called “China’s green development in the new era”, says that:
“Local authorities should rely on their resource endowments, environmental conditions and industrial development foundations to fully leverage the comparative advantages.”
TEMPERATURE WARMING: Global temperatures could hit nearly 2C above pre-industrial levels for the first time in the next five years, according to new data from the UN World Meteorological Organization (WMO) covered by the Financial Times. The outlet noted that this would not represent a breach of the Paris Agreement target of keeping warming below 2C, as this threshold is typically measured over at least two decades. However, it added that 2C of warming would result in a “fall in crop yields” and more than a third of the world’s population being exposed to extreme heat.
WILDFIRE EMERGENCY: Wildfires in Canada have forced thousands of people to flee their homes, CBC News reported. The government of Manitoba declared a state of emergency after evacuating 17,000 people and neighbouring province Saskatchewan followed suit a day later, CBC News said. Manitoba premier Wab Kinew said the prevalence of fire in “every region” was a “sign of a changing climate that we are going to have to adapt to”, according to Le Monde. BBC News noted that “scientists have linked worsening wildfire seasons to climate change”.
MONSOON IN MAY: Monsoon rains hit the coast of India’s southernmost state of Kerala eight days early, marking the earliest arrival of the rainy season in 16 years, Reuters reported. Just two days later, the rains reached Mumbai – the city’s earliest monsoon in 75 years, according to Business Standard. India Today said human-caused climate change and “natural climatic systems” played a role.
ALPINE DISASTER: A landslide of ice, mud and rocks triggered by the collapse of a glacier has buried a large part of the Swiss village of Blatten, Swissinfo reported. Climate scientist Christian Huggel told Reuters that climate change had “likely played a part in the deluge”, given that the loss of permafrost can “negatively affect the stability of mountain rock”. The Swiss army has been deployed to find a missing person, Reuters said.
The equivalent amount of primary tropical forest that was lost every minute in 2024, according to data from the World Resources Institute.
(For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Tuesday, Wednesday, Thursday and Friday.)
A new analysis by Carbon Brief of data from UK energy regulator Ofgem showed how the biggest driver of recent increases in electricity bills in the UK has been wholesale electricity prices – which in the UK are set almost exclusively by wholesale gas prices. In contrast, “green levies” – costs added to bills in order to pay for government climate policies – actually fell during the height of the gas price spike, as the dark grey area of the chart shows. This runs counter to opposition politicians’ claims that the UK’s high electricity prices are caused by its target for net-zero emissions by 2050 and green levies.
This week, Carbon Brief speaks to US climate scientists taking part in a 100-hour livestream aimed at raising awareness of their work and the risks they face.
Marathon livestreams are typically the preserve of video gamers, sex workers and chess stars – not climate scientists. But unusual times call for unusual measures.
Hundreds of climate scientists and meteorologists from across the US are this week participating in a 100-hour livestream, which aims to raise awareness of their work as the government gears up for a major programme of cuts to federal science agencies.
The broadcast runs day and night until Sunday afternoon on YouTube, with each speaker advised to dedicate their 30-45 minute session to presenting their research in layperson’s terms – with a mention of how it is or could be impacted by federal cuts to science.
The online event comes after the Trump administration set out plans to halve NASA’s science budget and shrink the National Oceanic and Atmospheric Administration (NOAA’s) funding by more than a quarter.
The livestream will be rolling while NASA’s climate and space monitoring lab, the Goddard Institute for Space Studies, is moving out of its New York building on 31 May, after the federal government abruptly terminated the space agency’s lease.
(The White House has also cancelled funding to the body that produces the country’s National Climate Assessment, blocked US scientists from attending Intergovernmental Panel for Climate Change meetings and laid off hundreds of workers at the agency responsible for hurricane preparations.)
Speaking to Carbon Brief in a personal capacity, climate scientist and keynote speaker Dr Kate Marvel described the livestream event as a “fire hose of public engagement”. She added:
“It is scientists making the case to the people we work for. We work for the American people because we receive taxpayer dollars. It is really important for us to share our results, to explain to people why what we do is important and to help them see themselves in what we do.”
At 1:30am California time – 4:30am New York time – on Thursday morning, more than 750 people were tuned in to the livestream, and the comment section was lively.
Some viewers shared words of encouragement – “not from the continent of America but still here to support!!! climate science affects us all!!!!” and “beautiful visualisations!”
Others focused on the science: “Look up the relationship between the Salton Sea and earthquakes – fascinating findings”, “does this mean misaligned storms have two different impacts on each level?” and “albedo effect [fire emoji]”.
Livestream organiser Dr Margaret Duffy, who studies cloud dynamics at the Massachusetts Institute of Technology, said the event’s “long format” is designed to underscore the “widespread” nature of the cuts. She told Carbon Brief:
“[It will] make clear that it’s not one or two programmes that are being cut, [nor] one or two researchers that are losing their funding. Researcher after researcher after researcher will explain what they do, and then make the connection to the cuts and what is happening to them.”
The audience is being pointed to materials to help them contact their political representatives about cuts to climate and weather research – but this is not an obligation, Duffy said, explaining that “at a very basic level, we just want to share with the public what it is that we do”.
Climate scientist Marvel commended the livestream organisers for “stepping up” amid much-justified “flailing” and “panic”, adding:
“We are not in normal times. There is a lot of fear and there’s a lot of reasons to be afraid. I think trouble may be coming for us – but we just need to make sure that we get in good trouble. [In other words] you shake things up, you maybe attract negative attention. Maybe it’s scary and maybe there are consequences. But ultimately, you are always going to be happy to have done the right thing.”
WATER CRISIS: Atmos Earth looked at how changing rainfall patterns are impacting the lives of Palestinians already denied access to water.
FRAGILE TEXTS: In a photo essay, Al Jazeera looked at how encroaching desert sands are threatening centuries-old manuscripts stored in Oualata, Mauritania.
LURCHING RIGHT: For Drilled, Amy Westervelt unpacked the structural issues in the US media hurting climate coverage.
DeBriefed is edited by Daisy Dunne. Please send any tips or feedback to debriefed@carbonbrief.org.
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China Briefing handpicks and explains the most important climate and energy stories from China over the past fortnight. Subscribe for free here.
ENVOY REMARKS: Xinhua published an exclusive interview with Chinese climate envoy Liu Zhenmin, in which he spoke about how China-Europe cooperation could make a “positive contribution” to combating climate change. In the interview, Liu said that developed countries were “generally worried about who will share the responsibilities that the US should bear” after its withdrawal from the Paris Agreement, adding that China “deeply regretted” the “shrinking space” for US-China climate cooperation. The outlet quoted Liu saying: “However, we must see that China and the US do not have fundamental differences in the field of climate change, but rather have broad space for cooperation.”
EU AMBIVELANCE: Meanwhile, the EU’s ambassador to China, Jorge Toledo, warned that the EU may not hold an expected “high-level economic [and] trade dialogue” with China in July, due to current negotiations over Chinese EV tariffs and supply chains “not making progress”, reported the Hong Kong-based South China Morning Post (SCMP). European countries, such as the Netherlands, France and Germany, on the other hand, have expressed interest in more collaboration in areas such as climate and the low-carbon transition, said state-supporting media the Global Times. Belinda Schäpe, China policy analyst at Centre for Research on Energy and Clean Air (CREA), nevertheless wrote on LinkedIn that while both China and Germany “expressed support” for tackling climate change, it is “unclear how this will translate into Germany’s position on cooperation in areas like energy transition or climate diplomacy”.
EARLY PEAK?: China’s emissions will “likely peak a few years ahead of its self-set deadline of 2030”, Bloomberg said, reporting comments by Zhu Guangyao, who was the country’s vice minister of finance from 2010-2018 and who cited analysis recently published by Carbon Brief. The outlet quoted Zhu saying: “It’s most likely China will realise the peak of carbon emissions a few years before 2030…That’s good news for China, also good news for Asia, for the whole world.” Meanwhile, the SCMP published a comment article by former UN secretary general Ban Ki-moon on China’s “green energy leadership”. In the article, Ban called on China to target a 30% reduction in emissions below 2023 levels by 2035 in its next international climate pledge (nationally determined contribution, NDC).
‘GREEN TRANSFORMATION’: China’s central government approved an action plan for “advancing the green and low-carbon development” of the manufacturing sector between 2025 and 2027 at a State Council executive meeting, reported state news agency Xinhua. The full text of the action plan is not yet public. The meeting called for “deep[ening the] green transformation of traditional industries” while “accelerat[ing] innovation in green technologies”, added the outlet. The state-owned newspaper Securities Daily said that the policy extends “intensive” regulatory support and will affect a range of industries, including steel, metals and construction. About 20% of the “total output of China’s manufacturing industry” in 2024 had already come from “national-level green [factory] plants”, added the newspaper. (According to the “general principals” outlined by the Chinese government, such plants have tighter requirements on their emissions of greenhouse gases and other pollutants.)
RECTIFY THE ‘RAT RACE’: Meanwhile, the National Development and Reform Commission (NDRC) commented on “neijuan” (内卷) – officially translated as “rat race competition” that leads to oversupply in affected industries, including clean energy, steel and oil refining, reported Xinhua. According to the newswire, the NDRC said at its May press conference that this “rat race” had “disrupted” fair competition and “must be rectified”. According to the NDRC transcript, government officials called for eliminating “inefficient and backward production capacity” in the oil refining and steel industries, “preventing blind new construction” in the coal chemical and aluminium industries, and “guiding” “new-energy vehicle” (NEV) and solar companies to “focus on technology research and development”. Nevertheless, the officials stated that the majority of the investments the NDRC had approved from January to April this year were still in the “energy” and “advanced technology” sectors, among others, reported Chinese media outlet Dazhong News. The NDRC also said its “two new” policy “stimulated green consumption” of products such as NEVs, according to the transcript. Separately, the production of NEVs rose by 39% in April, said the Communist party-affiliated People’s Daily, adding that China’s “shift toward intelligent and green development is gaining momentum”.
SOLAR RUSH: China installed a “record” 105 gigawatts (GW) of solar capacity between January and April 2025, industry outlet PV Tech said, citing a recent data release by the National Energy Administration (NEA). It added that “April alone” accounted for 45GW of new additions – compared to a total of 46GW solar installations in China between January and March 2024 – as a deadline set by a new renewable pricing policy “triggered a project installation rush”. [Outside China, the US is the only country in the world to have more than 105GW of solar capacity in total. The UK has 18GW.]
THERMAL FALL: Analysis by thinktank Climate Energy Finance found that the amount of new solar installations between January and April was eight times larger than that of new thermal capacity (13GW, mainly coal). It added that China’s coal plants were only running 46% of the time on average in the first four months of 2025, saying that this was a “record low”. Similarly, Reuters reported that “thermal power generation in China, fuelled mainly by coal, fell 2% in April and 4% from January to April amid slower overall power output growth”. New data from energy thinktank Ember found that wind and solar power generated 26% of the country’s electricity in April 2025, the “highest monthly share on record”.
ROOFTOP ‘BOOM’: Meanwhile, separate data from consultancy Rystad Energy found that, of the 60GW of solar installed between January and March 2025, rooftop solar installations accounted for 36GW, marking the “highest quarterly total for distributed solar in [China’s] history”, solar news outlet PV Magazine reported. Industry news outlet SolarQuarter said that, according to Rystad Energy’s forecasts, the rooftop solar installation “boom” will continue through to June 2025, “potentially pushing total distributed solar capacity additions for the year to 130GW”.
SOLAR CYBER SCARE: Reuters reported that the US government is “reassessing the risk posed by Chinese-made” renewable energy components after “rogue communication devices not listed in product documents ha[d] been found in some Chinese solar power inverters by US experts”. The newswire added that it “was unable to determine how many solar power inverters and batteries they have looked at”. Following this, the Japanese government also “launched an investigation into Chinese-made solar panels”, reported SCMP. Tom Nunlist, associate director at consultancy firm Trivium China, wrote on LinkedIn that while “an industrial-scale plot to disrupt the US power grid” cannot be ruled out, it is “far more likely that we’re dealing with commonplace bill of materials errors”. He added that “given the atmosphere, I think there’s a good chance this will get blown way out of proportion”. Meanwhile, the industry association SolarPower Europe called for stronger cybersecurity rules for Europe’s clean-energy installations, following the discovery of “unexplained electronic components in imported circuit boards from an unnamed country destined for [Denmark’s] energy infrastructure”, PV Magazine said. It added that the “suspicious elements were not solar components”.
RAIN AND FLOODING: Four people were killed by “torrential rain” in Guizhou province in southwest China and 17 people remained missing, reported Reuters on 23 May. China is facing “hotter and longer heatwaves and more frequent and unpredictable heavy rain as a result of climate change” and its “huge population” made the country “especially vulnerable to the effects of climate change, authorities have said”, added the outlet.
EXTREME HEAT: Temperatures in north China reached as high as 43C in May, according to China Qixiang Aihaozhe, a popular scientific blog. State broadcaster CGTN reported that many places in the provinces of Henan and Hebei broke local temperature records for May and that ground temperatures in “multiple places” broke 70C on 20 May. The outlet noted that May is a “critical” period for maximising wheat harvest yields. Reuters reported that China disbursed 1.4bn yuan ($194m) for “agricultural production disaster prevention and relief”. Meanwhile, cooling demand from air conditioners could drive electricity demand to be about 100GW higher than last year, Bloomberg cited the NEA as saying. Lauri Myllyvirta, lead analyst at CREA, posted on Bluesky that, even if this demand does disrupts the recent plateau in China’s emissions, the “structural trend” of clean-energy additions pushing overall emissions down will continue to drive reductions in the long-term.
The share of China’s overseas energy investments that went to solar and wind projects between 2022-2023, reported Inside Climate News citing data from Boston University’s Global Development Policy Center. Only 13% of investments had gone into solar and wind from 2000-2021, added the outlet, noting that 2021 was the year that China pledged to stop funding overseas coal projects.
Shenzhen, a city bordering Hong Kong that is known for pioneering China’s economic reforms, is leading the country in several carbon mitigation measures and is seen as a “pilot” for the construction of “low-carbon cities”.
Carbon Brief looks back at Shenzhen’s efforts to date and assesses its progress on carbon mitigation. The full article will be available on Carbon Brief’s website.
Since the 2000s, Shenzhen has developed strategies for “low-carbon development”. Part of this included nourishing the growth of a number of “strategic emerging industries”, such as “new-energy vehicles” (NEVs).
According to a government work report, Shenzhen – whose population makes up 1% of the country’s total – produced 22% of China’s NEVs in 2024. NEV also comprised 77% of the new car sales in Shenzhen last year, significantly higher than the national share of 48%.
The city has also replaced all of its buses, taxis and ride-hailing cars with electric versions – the first city to have done so in China.
Heran Zheng, lecturer in sustainable infrastructure economics and finance at University College London (UCL), told Carbon Brief that a city’s green transition mainly requires two focuses: “transport transition” and “industry decarbonisation”.
With no major heavy industries, Shenzhen has an “advantage” in industry low-carbon transition, said Zheng, which allows it to set “more ambitious” emissions targets.
Shenzhen was China’s “first city to explicitly state its commitment to the ‘dual control [of carbon]’ system”, according to Dialogue Earth. It issued two “implementation plans” towards this effort and developed a city-level carbon emissions cap.
Shenzhen plans to reduce its energy intensity by 14.5% before the end of 2025, compared to 2020 levels. The national energy intensity target is 13.5% during the same period.
Zheng said that Shenzhen’s commitment “should be within its capacity”, adding:
“There are three major carbon mitigation areas – steel, cement and electricity. Shenzhen has no major steel and cement industries, so it only needs to largely focus on electricity…In addition, the city is a technology hub. A lot of high-emission manufacturers have moved out of Shenzhen to its neighbouring cities.”
Another “big difference” between Shenzhen and other cities is that “Shenzhen has its own nuclear power”, said Zheng, which is “important” for the city’s electricity transition – the remaining sector that Shenzhen needs to put efforts on towards green transition.
According to a 2021 report, nuclear power is Shenzhen’s “largest local power source”. It contributed 35% of the city’s total power generation in 2021.
Nuclear dwarfs all the other clean energy sources feeding into the city’s grid. The Shenzhen local authority’s 2025 government work report says current solar power capacity stands at about 1GW – and it does not mention wind capacity.
Its “14th five-year plan for climate change response” says that Shenzhen’s renewable energy capacity has “little room” for future growth due to “scarce” energy resources and “limited” land for wind and solar power.
In 2024, China approved the construction of more nuclear reactors in Shenzhen’s neighbouring city of Huizhou.
The Shenzhen government also aims to “raise the combined share of natural gas, nuclear and renewable energy to 90% in 2025, up from the current figure of 77%, which is noticeably ahead of the nationwide figure of 52%”, according to research published in 2022.
Shenzhen was one of the first seven cities and provinces in China that established a local “pilot” emissions trading system (ETS) in 2013, ahead of the national rollout in 2021.
Yan Qin, carbon analyst at consultancy firm ClearBlue Markets, told Carbon Brief that despite Shenzhen’s plans to expand the coverage of its ETS, most pilot ETSs are seeing their coverage “shrinking” due to enterprises leaving to join the national ETS.
In the meantime, Shenzhen issued China’s first overseas sales of “green government bonds” in 2021 in Hong Kong. In contrast, China’s national sovereign bonds were only available to international buyers from April 2025.
Zheng said that the impact of the green bonds is “hard to evaluate”. He added that projects, such as sewage treatment, can “also fall into the category of ‘green bonds’”. Although linked to energy efficiency improvement, they nonetheless make only “limited contributions” to cutting carbon emissions, he added.
The local government and media outlets have touted the city’s achievements on climate as the “Shenzhen model”.
But Shenzhen’s journey is not all “replicable”, said Shen Xinyi, analyst and China team lead at the Centre for Research on Energy and Clean Air (CREA), adding that “Shenzhen capitalised on the opportunities of its era”.
Zheng said Shenzhen can “only represent a [certain] type of city in China, the ‘top tier’, such as Beijing, Shanghai and Guangzhou”. He added:
“There are more than 300 cities in China, all facing unique transition situations. It is meaningless for coal-heavy industrial cities to learn from Shenzhen.”
Other cities must “adapt strategies according to their unique conditions”, Shen added.
This report is by freelancing climate journalist Henry Zhang and Carbon Brief’s China section editor Wanyuan Song.
CRITICAL MINERALS: An episode of consulting firm Trivium China’s podcast discussed China’s critical mineral export controls.
‘MARSHALL PLAN’?: Sam Geall, Dialogue Earth’s outgoing chief executive officer, published a comment on China’s new role amidst shifting “climate politics”.
US-CHINA DECOUPLING: In an exclusive interview with Chinese financial media Caixin, Huang Hanquan, dean of the Chinese Academy of Macroeconomic Research – a thinktank under the direct management of NDRC – said there are still “risks” in US-China decoupling.
‘ZERO-CARBON’ PARKS: The 21st Century Business Herald, a Chinese media outlet, published an interview with Chai Qimin, director of the International Cooperation Department at the National Center for Climate Change Strategy and International Cooperation, a thinktank under the China’s Ministry of Ecology and Environment, talking about “zero-carbon industrial parks”.
Peer effects on rural household carbon emissions in China
Scientific Reports
New research found that the “peer effect” – a phenomenon where an individual’s behavior and attitudes are influenced by their peers – has a “significant positive impact” on carbon emissions in rural China. The paper quantified emissions from rural Chinese households over 2012-20 using data from “China family panel studies” and “carbon emission accounts and datasets”. The authors found that carbon emissions from “low social status families” are influenced by those of “high social status families”. They added that the “peer effect has a relatively greater impact on the carbon emissions of farmers in the eastern region”.
The impact of carbon news coverage on corporate green transformation
Scientific Reports
A new study of Chinese companies found that “carbon news coverage significantly enhances the corporate green transformation”. The authors examined the effect of “carbon news coverage” on the green transformation of “Chinese A-share listed enterprises” over 2013-21. They found that “carbon news coverage” can help enterprises with their “green transition” by “alleviating financing constraints, strengthening environmental information disclosure and increasing R&D investment”. They added that “carbon emissions trading market and carbon news coverage serve as multiple co-regulations of formal and informal environmental regulation, synergistically advancing enterprises’ green transformation”.
China Briefing is compiled by Wanyuan Song and Anika Patel. It is edited by Wanyuan Song and Dr Simon Evans. Please send tips and feedback to china@carbonbrief.org
Marine life plays a significant part in this process, as organisms transfer carbon from the ocean surface to the deep sea upon death or as they migrate.
Our new research, published in Nature Communications, suggests the contribution of ocean biology to climate regulation is more complex than previously thought.
To explore how ocean biology shapes the past, present and future climate, we explore an extreme scenario where all marine life has been wiped out.
We find that – in a pre-industrial climate – CO2 levels would rise by 50% without marine life, leading to 1.6C of global warming.
In a separate study in Nature Climate Change, we estimate that ocean biology sequesters the equivalent of 10bn tonnes of CO2 each year.
This is more than one quarter of annual fossil-fuel emissions from human activity.
We also calculate that the contribution of marine life to carbon storage is worth hundreds of billions of dollars each year.
The ocean takes up and stores vast amounts of CO2 every year through two mechanisms known as “carbon pumps”.
The first is the “solubility pump”. This is the process by which dissolved CO2 in seawater is transported from the ocean’s surface to its depth through the sinking and upwelling of water mass.
The second is the “biological carbon pump”. This is the process where carbon is converted into organic materials by plankton and other marine organisms at the ocean’s surface and then transported to the deep sea when they die or migrate.
Scientists have long known that the biological carbon pump played an essential role in maintaining low atmospheric CO2 levels before the industrial revolution.
However, the conventional view is that the solubility pump has been responsible for the ocean’s steady absorption of rising CO2 emissions caused by human activity.
Our findings challenge this view, by showing the biological carbon pump plays a crucial role in the modern ocean’s sequestration of atmospheric CO2.
We find that, without marine life, the ocean’s capacity to capture CO2 emissions would be significantly diminished.
To get an estimate of the contribution of the marine carbon pump in a stable pre-industrial climate, we simulate the planet’s climate as it was before the industrial era using a complex Earth system model.
(This is the second generation of the Norwegian Earth system model, which contributed to the sixth Coupled Model Intercomparison Project.)
We then explore what would happen to the Earth’s climate system under two scenarios:
In a pre-industrial scenario with no marine life, we find that atmospheric CO2 levels would rise to 445 parts per million (ppm). This is an increase of more than 50% on the “healthy ocean” scenario, where CO2 levels are 282ppm.
(This suggests that the influence of marine life on global CO2 levels is greater than the sum of all human activity, which has – so far – raised atmospheric CO2 concentrations to around 425ppm).
The rise in CO2 levels caused by the absence of marine life would result in about 1.64C of global warming at the surface and a 1.15C increase in global sea surface temperature.
This warming would have considerable impacts on the wider world, including declines in sea ice area at the Arctic and Antarctic of close to 25% and an Atlantic Meridional Overturning Circulation that was around 9% weaker.
The value of exploring such an extreme scenario is to investigate the role biological processes in the ocean play in carbon storage, as well as the implications of damage to marine life.
Our estimation that pre-industrial atmospheric CO2 would rise by 163ppm without ocean biology is on the lower end of the 150-240ppm range approximated by some previous studies.
However, previous estimates of the contribution of the biological carbon pump in a pre-industrial climate neglect the interactions between oceanic and terrestrial biospheres.
Our research reveals that terrestrial ecosystems – such as tropical forests and grasslands – play a crucial role in compensating for the increase in CO2 concentrations when ocean life declines. (This is due to the CO2 fertilisation effect, when higher CO2 concentrations speed up photosynthesis).
We find that in the extreme pre-industrial scenario, approximately half the carbon lost from the ocean is absorbed by the land.
The figure below illustrates the Earth’s carbon reservoirs in a pre-industrial climate with (left) and without (right) marine life. It shows how, if marine life is wiped out, carbon content decreases in the ocean and marine sediment, whereas more carbon accumulates in the atmosphere and on land.
Today, the ocean captures approximately 25% of human-caused CO2 emissions – which allows it to play a crucial role in slowing global warming.
In order to estimate the overall importance of marine life to carbon sequestration in the ocean, we also conduct experiments for various future emission pathways – both with, and without, marine life.
In all cases, we find that more CO2 emitted by human activities remains in the atmosphere when there is no marine life.
One might think that the ocean’s lower concentrations of carbon in the pre-industrial climate, relative to the atmosphere, might mean it would be able to absorb more additional carbon.
However, we find the absence of marine life fundamentally alters the vertical distribution of carbon in the ocean. Although the total amount of carbon stored is lower, there is more carbon at the surface due to an absence of organisms. This, in turn, hinders additional CO2 from entering the ocean.
Another surprising finding of the simulations was that the terrestrial biosphere’s capacity to absorb excess CO2 by increasing its vegetation mass diminishes over time, potentially due to limited nutrients.
The figure below shows the distribution of human-caused CO2 in the Earth’s carbon reservoirs under two 2100 scenarios. The chart on the left shows a scenario with ocean life, and the chart on the right shows one without ocean biology.
It illustrates how, without marine life, more CO2 stays in the atmosphere and less goes into the land and the ocean.
The study shows that in the absence of marine life, future warming would occur faster and more intensely.
This acceleration in warming would potentially trigger other processes that could further amplify warming, such as greater ocean stratification, longer sea-ice free Arctic summers and greater loss of permafrost.
Damaging marine life is economically costly given the many and various benefits – or “ecosystem services” – provided by carbon sequestration.
We estimate that the sinking of organic matter sequesters approximately 2.8bn tonnes of carbon annually, locking it away from the atmosphere for at least 50 years.
This carbon sequestration capacity is equivalent to 10bn tonnes of atmospheric CO2 – or roughly 27% of emissions generated by fossil fuels in 2024.
We estimate – based on a carbon price of $90 per tonne of CO2 – that the carbon storage provided by the marine carbon pump is worth $545bn per year in international waters and $383bn per year within national waters. Its total value is projected to exceed $2.2tn by 2030.
Carbon storage is valuable because it helps avoid climate impacts.
This economic value is important for developing countries, particularly small island developing states whose national waters are collectively responsible for 11% of biological carbon pump sequestration activity, in terms of carbon stored.
The top eight countries where the biological carbon pump value is highest in proportion to gross domestic product (GDP) are small island states. These are the Cook Islands, Kiribati, the Marshall Islands, Micronesia, Nauru, Niue, Palau and Tuvalu. Of these nations, just one – the Cook Islands – is classified by the World Bank as high income.
These climate-impacted nations’ key role in preserving ocean health should be considered in discussions of international climate finance.
The figure below shows the economic value of carbon sequestration of the biological carbon pump for each of these eight small island states, calculated on the basis of a carbon price of $90 per tonne of CO2.
For example, it illustrates how Micronesia and Kiribati have an estimated biological carbon pump value of $4,620m and $8,525m each year, respectively.
A healthy ocean buys the world time in the battle against global warming, but the window to protect it is closing rapidly.
Marine ecosystems remain vulnerable to a raft of human activities, including industrial fishing, pollution, shipping and deep-sea mining. Stronger conservation policies, enhanced financial incentives for lower income countries and increased international cooperation are essential to protect the services provided by ecosystems.
These are important steps towards not only protecting 30% of the global ocean as agreed under the new Global Biodiversity Framework – but it will help to reach the Paris Agreement’s climate target.
There are a number of tools at governments disposal to protect the valuable services provided by marine ecosystems. This includes promoting sustainable fishing and ecotourism, establishing marine protected areas and undertaking robust environmental impact assessments.
Nations can also support protection of the biological heat pump within international waters by ratifying the High Seas Treaty, which recognises the importance of protecting biogeochemical cycles.
