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The first-ever international conference on the contentious topic of “overshoot” was held last week in a palace in the small town of Laxenburg in Austria.

The three-day conference brought together nearly 200 researchers and legal experts to discuss future temperature pathways where the Paris Agreement’s “aspirational” target to limit global warming to 1.5C is met “from above, rather than below”.

Overshoot pathways are those which exceed the 1.5C limit – before being brought back down again through techniques that remove carbon from the atmosphere.

The conference explored both the feasibility of overshoot pathways and the legal frameworks that could help deliver them.

Researchers also discussed the potential consequences of a potential rise – and then fall – of global temperatures on climate action, society and the Earth’s climate systems.

Speaking during a plenary session, Prof Joeri Rogelj, a professor of climate science and policy at Imperial College London, said that “moving into a world where we exceed 1.5C and have to manage overshoot” was an exercise in “managing failure”.

He said that it was “essential” that this failure was acknowledged, explaining that this would help set out the need to “minimise and manage” the situation and clarify the implications for “near-term action” and “long-term [temperature] reversal”.

Below, Carbon Brief draws together some of the key talking points, new research and discussions that emerged from the event.

Defining overshoot

The study of temperature overshoot has grown in recent years as the prospects of limiting global temperature rise to 1.5C have dwindled.

Conference organiser Dr Carl-Friedrich Schleussner – a senior research scholar at the International Institute for Applied Systems Analysis (IIASA) – explained the event was designed to bring together different research communities working on a “new field of science”.

He told Carbon Brief:

“If we look at [overshoot] in isolation, we may miss important parts of the bigger picture. That’s why we also set out the conference with very broad themes and a very interdisciplinary approach.”

The conference was split between eight conference streams: mitigation ambition; carbon dioxide removal (CDR); Earth system responses; climate impacts; tipping points; adaptation; loss and damage; and legal implications.

There was also a focus on how to communicate the concept of overshoot.

In simple English, “overshoot” means to go past or beyond a limit. But, in climate science, the term implies both a failure to meet a target – as well as subsequent action to correct that failure.

Today, the term is most often deployed to describe future temperature trajectories that exceed the Paris Agreement’s 1.5C limit – and then come back down.

(In the Intergovernmental Panel on Climate Change’s (IPCC’s) fifth assessment cycle, completed in 2014, the term was used to describe a potential rise and then fall of CO2 concentrations above levels recommended to meet long-term climate goals. A recent “conceptual” review of overshoot noted this was because, at the time, CO2 concentrations were the key metric used to contextualise emissions reductions).

The plot below provides an illustration of three overshoot pathways. The most pronounced pathway sees global temperatures rise significantly above the 1.5C limit – before eventually falling back down again as carbon dioxide is pulled from the atmosphere at scale.

In the second and third pathways, global temperature rise breaches the limit by a smaller margin, before either falling enough just to stabilise around 1.5C, or dropping more dramatically due to larger-scale carbon removals.

Chart amended from Schleussner et al 2024
Credit: Amended from Schleussner et al (2024).

In an opening address to delegates, Prof Jim Skea, who is the current chair of the IPCC, acknowledged the scientific interpretation of overshoot was not intuitive to non-experts.

“The IPCC has mainly used two words in relation to overshoot – “exceeding” and “limiting”. To a lay person, these can sound like opposites. Yet we know that a single emissions pathway can both exceed 1.5C in the near term and limit warming to 1.5C in the long term.”

Noting that different research communities were using the term differently, Skea urged researchers to be precise with terminology and stick to the IPCC’s definition of overshoot:

“We should give some thought to communication and keep this as simple as possible. When I look at texts, I hear more poetic words like “surpassing” and “breaching”. I would urge you to keep the range of terms as small as possible and make sure that we’re absolutely using them consistently.”

In the glossary for its latest assessment cycle, AR6, the IPCC defines “overshoot” pathways as follows:

Overshoot pathways ragout

IIASA’s Schleussner stressed that not all pathways that go beyond 1.5C qualify as overshoot pathways:

“The most important understanding is that overshoot is not any pathway that exceeds 1.5C. An overshoot pathway is specific to this being a period of exceedance. It is going to come back down below 1.5C.”

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Mitigation ambition and 1.5C viability

Perhaps the most prominent topic during the conference was the implications of overshoot for global ambition to cut carbon emissions and the viability of the 1.5C limit.

Opening the conference, IIASA director general Prof Hans Joachim Schellnhuber shared his personal view that “1.5C is dead, 2C is in agony and 3C is looming”.

In a pre-recorded keynote speech, Ralph Regenvanu, Vanuatu’s minister for climate change, called for a rejection of the “normalisation of overshoot” and argued that “we must treat 1.5C as the absolute limit that it is” and avoid backsliding. He added:

“Minimising peak warming must be our lodestar, because every tenth of a degree matters.”

Prof Skea opened his keynote with some theology:

“I’m going to start with the prayer of St Augustine as he struggled with his youthful longings: ‘Lord grant me chastity and continence, but not yet.’ And it does seem that this is the way that the world as a whole is thinking about 1.5C: ‘Lord, limit warming to 1.5C above pre-industrial levels, but not yet.’”

Referencing the “lodestar” mentioned by Regenvanu, Skea warned that it is light years away and, “unless we act with a sense of urgency, [1.5C is] likely to remain just as remote”.

Speaking to Carbon Brief on the sidelines of the conference, Skea added:

“We are almost certain to exceed 1.5C and the viability of 1.5C is now much more referring to the long-term potential to limit it through overshoot.”

Schleussner told Carbon Brief that the framing of 1.5C in the conference is “one that further solidifies 1.5C as the long-term limit and, therefore, provides a backstop against the idea of reducing or backsliding on targets”.

If warming is going to surpass 1.5C, the next question is when temperatures are going to be brought back down again, Schleussner added, noting that there has been no “direct” guidance on this from climate policy:

“The [Paris Agreement’s] obligation to “pursue efforts” [to limit global temperature rise by 1.5C] points to doing it as fast as possible. Scientifically, we can determine what this means – and that would be this century. But there’s no clear language that gives you a specific date. It needs to be a period of overshoot – that is clear – and it should be as short as possible.”

In a parallel session on the “highest possible mitigation ambition under overshoot”, Prof Joeri Rogelj, professor of climate science and policy at Imperial College London, outlined how the recent ruling from the International Court of Justice (ICJ) provides guidance to countries on the level of ambition in their climate pledges under the Paris Agreement, known as “nationally determined contributions” (NDCs). He explained:

“[The ruling] highlights that the level of NDC ambition is not purely discretionary to a state and that every state must do its utmost to ensure its NDC reflects the highest possible ambition to meet the Paris Agreement long-term temperature goal.”

Rogelj presented some research – due to be published in the journal Environmental Research Letters – on translating the ICJ’s guidance “into a framework that can help us to assess whether an NDC indeed is following a standard of conduct that can represent the highest level of ambition”. He showed some initial results on how the first two rounds of NDCs measure up against three “pillars” covering domestic, international and implementation considerations.

In the same session, Prof Oliver Geden, senior fellow and head of the climate policy and politics research cluster at the German Institute for International and Security Affairs and vice-chair of IPCC Working Group III, warned that the concept of returning temperatures back down to 1.5C after an overshoot is “not a political project yet”.

He explained that there is “no shared understanding that, actually, the world is aiming for net-negative”, where emissions cuts and CDR together mean that more carbon is being taken out of the atmosphere than is being added. This is necessary to achieve a decline in global temperatures after surpassing 1.5C.

This lack of understanding includes developed countries, which “you would probably expect to be the frontrunners”, Geden said, noting that Denmark is the “only developed country that has a quantified net-negative target” of emission reductions of 110% in 2050, compared to 1990 levels. (Finland also has a net-negative target, while Germany announced its intention to set one last year. In addition, a few small global-south countries, such as Panama, Suriname and Bhutan, have already achieved net-negative.)

Geden pondered whether developed countries are a “little bit wary to commit to going to net-negative territory because they fear that once they say -110%, some countries will immediately demand -130% or -150%” to pay back a larger carbon debt.

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Carbon removal

To achieve a decline in global temperatures after an initial breach of 1.5C would require the world to reach net-negative emissions overall.

There is a wide range of potential techniques for removing CO2 from the atmosphere, such as afforestation, direct air capture and bioenergy with carbon capture and storage (BECCS). Captured carbon must be locked away indefinitely in order to be effective at reducing global temperatures.

However, despite its importance in achieving net-negative emissions, there are “huge knowledge gaps around overshoot and carbon dioxide removal”, Prof Skea told Carbon Brief. He continued:

“As it’s very clear from the themes of this conference, we don’t altogether understand how the Earth would react in taking carbon dioxide out of the atmosphere. We don’t understand the nature of the irreversibilities. And we don’t understand the effectiveness of CDR techniques, which might themselves be influenced by the level of global warming, plus all the equity and sustainability issues surrounding using CDR techniques.”

Skea notes that the seventh assessment cycle of the IPCC, which is just getting underway, will “start to fill these knowledge gaps without prejudging what the appropriate policy response should be”.

Prof Kristie Ebi, Dr Jonathan Donges. Prof Debra Roberts, Prof Deliang Chen, Dr Matt Gidden, Dr Annika Högner and Dr Keywan Riahi at a plenary session at the Overshoot Conference.
Prof Kristie Ebi, Dr Jonathan Donges, Prof Debra Roberts, Prof Deliang Chen, Dr Matt Gidden, Dr Annika Högner and Dr Keywan Riahi at a plenary session at the Overshoot Conference. Credit: IIASA

Prof Nebojsa Nakicenovic, an IIASA distinguished emeritus research scholar, told Carbon Brief that his “major concern” was whether there would be an “asymmetry” in how the climate would respond to large-scale carbon removal, compared to its response to carbon emissions.

In other words, he explained, would global temperatures respond to carbon removal “on the way down” in the same way they did “on the way up” to the world’s carbon emissions.

Nakicenovic noted that overshoot requires a change in focus to approaching the 1.5C limit “from above, rather than below”.

Schleussner made a similar point to Carbon Brief:

“We may fail to pursue [1.5C] from below, but it doesn’t relieve us from the obligation to then pursue it from above. I think that’s also a key message and a very strong overarching message that’s going to come out from the conference that we see…that pursuing an overshoot and then decline trajectory is both an obligation, but it also is well rooted in science.”

Reporting back to the plenary from one of the parallel sessions on CDR, Dr Matthew Gidden, deputy director of the Joint Global Change Research Institute at the Pacific Northwest National Laboratory, also noted another element of changing focus:

“When we’re talking about overshoot, we have become used to, in many cases, talking about what a net-zero world looks like. And that’s not a world of overshoot. That’s a world of not returning from a peak. And so communicating instead about a net-negative world is something that we could likely be shifting to in terms of how we’re communicating our science and the impacts that are coming out of it.”

On the need for both CDR and emissions cuts, Gidden noted that the discussions in his session emphasised that “CDR should not be at the cost of mitigation ambition”. But, he added, there is still the question of how “we talk about emission reductions needed today, but also likely dependence on CDR in the future”.

In a different parallel session, Prof Geden also made a similar point, noting that “we have to shift CDR from being seen as a barrier to ambition to an enabler of even higher ambition, but not doing that by betting on ever more CDR”.

Among the research presented in the parallel sessions on CDR was a recent study by Dr Jay Fuhrman from the JGCRI on the regional differences in capacity to deploy large-scale carbon removal. Ruben Prütz, from the Potsdam Institute for Climate Impact Research, presented on the risks to biodiversity from large-scale land-based CDR, which – in some cases – could have a larger impact than warming itself.

In another talk, the University of Oxford’s Dr Rupert Stuart-Smith explored how individual countries are “depending very heavily on [carbon] removals to meet their climate targets”. Stuart-Smith was a co-author on an “initial commentary” on the legal limits of CDR, published in 2023. This has been followed up with a “much more detailed legal analysis”, which should be published “very soon”, he added.

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Impacts of overshoot

Since the Paris Agreement and the call for the IPCC to produce a special report on 1.5C, research into the impacts of warming at the aspirational target has become commonplace.

Similarly, there is an abundance of research into the potential impacts at other thresholds, such as 2C, 3C and beyond.

However, there is comparatively little research into how impacts are affected by overshoot.

The conference included talks on some published research into overshoot, such as the chances of irreversible glacier loss and lasting impacts to water resources. There were also talks on work that is yet to be formally published, such as the risks of triggering interacting tipping points under overshoot.

Speaking in a morning plenary, Prof Debra Roberts, a coordinating lead author on the IPCC’s forthcoming special report on climate change and cities and a former co-chair of Working Group II, highlighted the need to consider the implications of different durations and peak temperatures of overshoot.

For example, she explained, it is “important to know” whether the impacts of “overshoot for 10 years at 0.2C above 1.5C are the same as 20 years at 0.1C of overshoot”.

Discussions during the conference noted that the answer may be different depending on the type of impact. For heat extremes, the peak temperature may be the key factor, while the length of overshoot will be more relevant for cumulative impacts that build up over time, such as sea level rise.

Similarly, if warming is brought back down to 1.5C after overshoot, what happens next is also significant – whether global temperature is stabilised or net-negative emissions continue and warming declines further. Prof Schleussner told Carbon Brief:

“For example, with coastal adaptation to sea level rise, the question of how fast and how far we bring temperatures back down again will be decisive in terms of the long-term outlook. Knowing that if you stabilise that around 1.5C, we might commit two metres of sea level rise, right? So, the question of how far we can and want to go back down again is decisive for a long-term perspective.”

One of the eight themes of the conference centred specifically on the reversibility or irreversibility of climate impacts.

In his opening speech, Vanuatu’s Ralph Regenvanu warned that “overshooting 1.5C isn’t a temporary mistake, it is a catalyst for inescapable, irreversible harm”. He continued:

“No level of finance can pull back the sea in our lifetimes or our children’s. There is no rewind button on a melted glacier. There is no time machine for an extinct species. Once we cross these tipping points, no amount of later ‘cooling’ can restore our sacred reefs, it cannot regrow the ice that already vanished and it cannot bring back the species or the cultures erased by the rising tides.”

As an example of a “deeply, deeply irreversible” impact, Dr Samuel Lüthi, a postdoctoral research fellow in the Institute of Social and Preventive Medicine at the University of Bern, presented on how overshoot could affect heat-related mortality.

Using mortality data from 850 locations across the world, Lüthi showed how projections under a pathway where warming overshoots 1.5C by 0.1-0.3C, before returning to 1.5C by 2100 has 15% more heat-related deaths in the 21st century than a pathway with less than 0.1C of overshoot.

His findings also suggested that “10 years of 1.6C is very similar [in terms of impacts] to five years of 1.7C”.

Extreme heat also featured in a talk by Dr Yi-Ling Hwong, a research scholar at IIASA, on the implications of using solar geoengineering to reduce peak temperatures during overshoot.

She showed that a world where a return to 1.5C had been achieved through geoengineering would see different impacts from a world where 1.5C was reached through cutting emissions. For example, in her modelling study, while geoengineering restores rainfall levels for some regions in the global north, significant drying “is observed in many regions in the global south”.

Similarly, a world geoengineered to 1.5C would see extreme nighttime heat in some tropical regions that is more severe than in a 2C world with no geoengineering, Hwong added.

In short, she said, “this implies the risk of creating winners and losers” under solar geoengineering and “raises concerns about equity and accountability that need to be considered”.

After describing how overshoot features in the outlines of the forthcoming AR7 reports in his opening speech, Prof Skea told Carbon Brief that he expects a “surge of papers” on overshoot in time to be included.

But it was important to emphasise that a “lot of the science that people have been carrying out is relevant within or without an overshoot”, he added:

“At points in the future, we are not going to know whether we’re in an overshoot world or just a high-emissions world, for example. So a lot of the climate research that’s been done is relevant regardless of overshoot. But overshoot is a new kind of dimension because of this issue of focus on 1.5C and concerns about its viability.”

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Adaptation

The implications of overshoot temperature pathways for efforts to prepare cities, countries and citizens for the impacts of climate change remains an under-researched field.

Speaking in a plenary, Prof Kristie Ebi a professor at the University of Washington’s Center for Health and the Global Environment – described research into adaptation and overshoot as “nascent”. However, she stressed that preparing society for the impacts associated with overshoot pathways was as important as bringing down emissions.

She told Carbon Brief that there were “all kinds of questions” about how to approach “effective” adaptation under an overshoot pathway, explaining:

“At the moment, adaptation is primarily assuming a continual increase in global mean surface temperature. If there is going to be a peak – and, of course, we don’t know what that peak is – then how do you start planning? Do you change your planning? There are places, for instance when thinking about hard infrastructure, [where overshoot] may result in a change in your plan.”

IIASA’s Schleussner told Carbon Brief that the scientific community was only just “beginning to appreciate” the need to understand and “quantify” the implications of different overshoot pathways on adaptation.

In a parallel session, Dr Elisabeth Gilmore, associate professor in environmental engineering and public policy at Carleton University in Canada, made the case for overshoot modelling pathways to take greater account of political considerations.

“Not just, but especially, in situations of overshoot, we need to start thinking about this as much as a physical process as a socio-political process…If we don’t do this, we are really missing out on some key uncertainties.”

Current scenarios used in climate research – including the Shared Socioeconomic Pathways and Representative Concentration Pathways – are “a bit quiet” when it comes to thinking about governance, institutions and peace and conflict, Gilmore said. She added:

“Political institutions, legitimacy and social cohesion continue to shift over time and this is really going to shape how much we can mitigate, how much we adapt and especially how we would recover when adding in the dimension of overshoot.”

Gilmore argued that, from a social perspective, adaptation needs are greatest “before the peak” of temperature rise – because this is when society can build the resilience to “get to the other side”. She said:

“Orthodoxy in adaptation [research] that you always want to plan for the worst [in the context of adaptation, peak temperature rise]… But we don’t really know what this peak is going to be – and we know that the politics and the social systems are much more messy.”

Dr Marta Mastropietro, a researcher at Politecnico di Milano in Italy, presented the preliminary results of a study that used emulators – simple climate models – to explore how human development might be impacted under low, medium and high overshoot pathways.

Mastropietro noted how, under all overshoot scenarios studied, both the drop to the human development index (HDI) – an index which incorporates health, knowledge and standard of living – and uncertainty increases as the peak temperature increases.

However, she said “the most important takeaway” from the preliminary results was around society’s constrained ability to recover from damage.

“This percentage of damages that are absorbed is always less than 50%. So, even in the most optimistic scenarios of overshoot, we will not be able to reabsorb these damages, not even half of them. And this is considering a damage function which does not consider irreversible impacts like sea level rise.”

Meanwhile, Dr Inês Gomes Marques from the University of Lisboa in Portugal, shared the results of an as-yet-unpublished study investigating whether the Lisbon metropolitan area holds enough public spaces to offer heatwave relief to the population under overshoot scenarios. The 1,900 “climate refugia” counted by researchers included schools, museums and churches.

Marques noted that most of the population were found to be within one kilometre of a “climate refugia” – but noted that “nuances” would need to be added to the analysis, including a function which considers the limited mobility of older citizens.

She explained that the researchers were aiming to “establish a framework” for this type of analysis that would be relevant to both the science community and municipalities tasked with adaptation. She added:

“The main point is that we need to think about this now, because we will face some big problems if we don’t”.

Delegates attend a poster session at the Overshoot Conference. Credit: IIASA
Delegates attend a poster session at the Overshoot Conference. Credit: IIASA

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Legal implications and loss and damage

Significant attention was given throughout the conference to the legal considerations of the breach of – and impetus to return to – the Paris Agreement’s 1.5C warming limit.

This included discussions about how the international legal frameworks should be updated for an “overshoot” world where countries would need to pursue “net-negative” strategies to bring temperatures down to 1.5C.

There were also discussions around governance of geoengineering technologies and the fairness and justice considerations that arise from the real-world impacts of breached targets.

The conference was being held just months after the ICJ’s advisory decision that limiting temperature increase to 1.5C should be considered countries’ “primary temperature goal”.

IIASA’s Shleussner told Carbon Brief that the decision provided “clarity” that countries had a “clear obligation to bring warming back to 1.5C”. He added:

“We may fail to pursue it from below, but it doesn’t relieve us from the obligation to then pursue it from above.”

Prof Lavanya Rajamani, professor of international environmental law at the University of Oxford, insisted that “1.5C was very much alive and well in the legal world”, but noted there were “very significant limits” to what could be achieved through the UN Framework Convention for Climate Change (UNFCCC) – the global treaty for coordinating the response to climate change – both today and in the future.

Summarising discussions around how countries can be pushed to deliver the “highest possible ambition” in future climate plans submitted to the UN, Rajamani urged delegates to be “tempered in [its] expectations of what we’re going to get from the international regime”. She added:

“Changing the narratives and practices at the national level are far more likely to filter up to the international level than trying to do it from a top-down perspective.”

In a parallel session, Prof Christina Voigt, a professor of international law at the University of Oslo, pointed out that overshoot would require countries to aspire beyond “net-zero emissions” as “the end climate goal” in national plans.

Stabilising emissions at “net-zero” by mid-century would result in warming above 1.5C, she explained, whereas “net-negative” emissions are required to deliver overshoot pathways that return temperatures to below the Paris Agreement’s aspirational limit. She continued:

“We will need frontrunners. Leaders, states, regions would need to start considering negative-emission benchmarks in their climate policies and laws from around mid-century. There will be an expectation that developed country parties take the lead and explore this ‘negativity territory’.”

Voigt added that it was “critical” that nations at the UNFCCC create a “shared understanding” that 1.5C remains the “core target” for nations to aim for, even after it has been exceeded. One possible place for such discussions could be at the 2028 global stocktake, she noted.

She said there would need to be more regulation to scale up CDR in a way that addresses “environmental and social challenges” and an effort to “recalibrate policies and measures” – including around carbon markets – to deliver net-negative outcomes.

In a presentation exploring governance of solar radiation management (SRM), Ewan White, a DPhil student in environmental law at the University of Oxford, said the ICJ’s recent advisory opinion could be interpreted to be “both for and against” solar geoengineering.

Countries tasked with drawing up global rules around SRM in an overshoot world would need to take a “holistic approach to environmental law”, White said. In his view, this should take into account international legal obligations beyond the Paris Agreement and consider issues of intergenerational equity, biodiversity protection and nations’ duty to cooperate.

Dr Shonali Pachauri, research group leader at IIASA, provided an overview of the equity and justice implications that might arise in an overshoot world.

First, she said that delays to emissions reductions today are “shifting the burden” to future generations and “others within this generation” – increasing the need for “corrective justice” and potential loss-and-damage payments.

Second, she said that adaptation efforts would need to increase – which, in turn, would “threaten mitigation ambition” given “constrained decision-making”.

Finally, she pointed to resource consumption issues that might arise in a world of overshoot:

“The different technologies that one might use for CDR often depend on the use of land, water, other materials – and this, of course, then means competing with many other uses [of resources].”

A separate stream focused on loss and damage. Session chair Dr Sindra Sharma, international policy lead at the Pacific Islands Climate Action Network, noted that the concept of loss and damage was “fundamentally transformed” by overshoot – adding there were “deep issues of justice and equity”.

However, Sharma said that the literature on loss and damage “has not yet deeply engaged with the specific concept of overshoot” despite it being “an important, interconnected issue”.

Sessions on loss and damage explored the existence of “hard social limits” under future overshoot scenarios, insurance and the need to bring more factors into assessments of habitability, including biophysical and social-economic constraints.

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Communication challenges and next steps

At the conference, scientists and legal experts collaborated on a series of statements that summarised discussions at the conference – one for each research theme and an overarching umbrella statement.

IIASA’s Schleussner told Carbon Brief that the statements represented a “key outcome of the conference” that could provide a “framework” to guide future research.

Nevertheless, he noted that statements are a “work in progress” and set to be “further refined” following feedback from experts not able to attend the conference.

At the time of going to press, the overarching conference statement read as follows:

“Global warming above 1.5C will increase irreversible and unacceptable losses and damages to people, societies and the environment.

“It is imperative to minimise both the maximum warming and duration of overshoot above 1.5C to reduce additional risks of human rights violations and causing irreversible social, ecological and Earth system changes including transgressing tipping points.

“This is required by international law and possible by removing CO2 from the atmosphere and further reducing remaining greenhouse emissions.”

Conference organisers also pointed delegates to an open call for research on “pathways and consequences of overshoot” in the journal Environmental Research Letters. The special issue will be guest edited by a number of scientists who played a key role in the conference.

Meanwhile, communications experts at the conference discussed the challenges inherent in conveying overshoot science to non-experts, noting potential confusion around the word “overshoot” and the difficulties in explaining that the 1.5C limit, while breached, was still a goal.

Holly Simpkin, communications manager at the Potsdam Institute for Climate Impact Research, urged caution when communicating overshoot science to the general public:

“I don’t know whether ‘overshoot’ is an effective communication framing. It is an important scientific question, but when it comes to near-term action and the requirements that an ambitious overshoot pathway would ask of us, emissions are what are in our control.

“We could spend 10 more years defining this and, actually, it’s quite complex…I think it’s better to be honest about that and to try to be more simple in that frame of communication, knowing that this community is doing a wealth of work that provides a technical basis for those discussions.”

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Overshoot: Exploring the implications of meeting 1.5C climate goal ‘from above’

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Analysis: Wind and solar power overtake fossil fuels in Germany for first time ever

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More of Germany’s electricity came from wind and solar power than fossil fuels for the first time ever in 2025.

Together, wind and solar power generated 225 terawatt hours (TWh) of electricity – accounting for 44% of the total in 2025 – with just 217TWh (43%) coming from fossil fuels.

Solar and onshore wind have grown rapidly under Germany’s “Energiewende” strategy over the past two decades, as the nation transitions away from both coal and nuclear power.

Renewables have recently faced mounting opposition from the far-right Alternative for Germany (AfD) party and the current coalition government has been trying to develop new gas-power plants.

Nevertheless, Carbon Brief analysis of Energy Institute data – shown in the chart below – illustrates how wind and solar have continued growing, emerging as the nation’s largest power source.

The success of renewables in Germany mirrors the EU as a whole, which also saw wind and solar overtake fossil-fuel power generation in 2025 for the first time.

“Other renewables” includes hydropower, bioenergy, geothermal and other renewable sources not otherwise stated. Source: Energy Institute Statistical Review of World Energy, 2026.

Germany has various targets in place that require a rapid expansion of wind and solar power, including cutting economy-wide emissions to net-zero by 2045.

The nation is also aiming to increase renewables’ share of electricity consumption to 80% by 2030 to achieve a “largely climate neutral” power system by 2035. It aims to decarbonise its electricity entirely once coal power has been phased out, which has a deadline of “no later than” 2038.

(The renewables targets also include electricity generated from hydropower and bioenergy. The latter produces a relatively large share of Germany’s power – roughly a tenth in 2025.)

Germany has to rely on renewables more than neighbours, such as France and the UK, to achieve its climate goals. This is due to its phaseout of nuclear power, which is a key part of the “Energiewende” strategy.

Nuclear power has long faced widespread public opposition in Germany. This year, the centre-right chancellor Friedrich Merz described the nuclear phaseout as a “strategic mistake”, but the government has ruled out a return to conventional nuclear power.

The country has an official coal phaseout date of 2038, but experts say the country is on track to eliminate coal from its power supply years earlier. This is despite some pressure to temporarily slow the transition away from coal during the recent energy crisis.

(Very few outside the AfD are calling to scrap the coal phaseout altogether, but the government will publish a review of the timelines in August.)

While coal generation has fallen quickly, even as nuclear was being phased out, some argue that coal could have been cut more quickly if nuclear had remained.

Gas-power expansion has also been framed by the government in recent years as an essential component of Germany’s transition away from coal and nuclear power, to support a renewables-heavy grid.

The current government under Merz has tried to boost gas and recently adopted a law to provide state support for new gas-fired power plants. The plan is for these plants to be converted to run on “green hydrogen” by 2045, in order to meet the climate-neutrality goal.

Germany aims to install 115 gigawatts (GW) of onshore wind by 2030 and approved a record 20.8GW of new capacity in 2025. 

Meanwhile, solar generation has reached unprecedented levels during the hot summer of 2026.

However, the government’s planned grid reforms have been criticised by the renewables industry for risking slowing down the energy transition. Under the proposals, renewables developers would only be granted automatic grid connections in areas with limited grid capacity if they waive compensation for future curtailed generation.

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Analysis: Wind and solar power overtake fossil fuels in Germany for first time ever

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Analysis: 84% of nations miss deadline to identify ‘nature-harming’ subsidies by 2025 

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Most countries failed to meet a 2025 target to identify all of their subsidies that could be “harmful” to biodiversity, according to Carbon Brief analysis.

The findings also reveal that 32 countries spend an estimated $270bn on biodiversity-harming subsidies and other incentives each year.

This is the “tip of the iceberg”, one expert notes, with “trillions” spent globally.

In 2022, almost every country in the world agreed on a set of “goals” and “targets” aiming to halt and reverse biodiversity loss by 2030.

One of these targets asked countries to identify all subsidies that damage biodiversity by 2025, before phasing out or reforming at least $500bn of these incentives by 2030.

The subsidies can be found in a range of sectors, including fossil fuels, agriculture, forestry, mining and fishing.

Just 21 countries appear to have met the 2025 goal, Carbon Brief finds, based on analysis of 134 national reports submitted to the UN Convention on Biological Diversity (CBD) by 1 July 2026.

Five of the world’s 17 megadiverse countries were among those that met the deadline.

Country progress

Carbon Brief’s analysis looks at the number of countries that have met the 2025 target to identify their use of nature-harming subsidies.

However, the metrics to determine which countries have “met” this target are not explicitly defined.

Carbon Brief included any country that says it has completed the process of identifying its subsidies. In almost every case, these countries also included a total figure for the value of those subsidies.

The analysis finds that 21 countries say they have identified their harmful subsidies, as shown in the map below (yellow). This amounts to 16% of the countries that have submitted national reports so far.

A further 11 countries, plus the EU, have provided figures for some of their subsidies, such as only those in a specific sector (dark blue).

Of the 134 national reports submitted to the CBD, 66 make reference to beginning the process (medium blue), while the remaining 68 do not (light blue). The final 62 countries party to the CBD have yet to submit a national report (light grey).

(Every country in the world participates in the CBD, except for the US and the Holy See – the governing body of the Catholic church, which is seated in Vatican City.)

Map of the world showing that 21 countries have identified all of their nature-harming subsidies
Countries that have identified all of their harmful subsidies (yellow); provided figures for some sectors (dark blue); begun the process, but not provided any numbers (medium blue); not begun the process (light blue); and not submitted a national report to the CBD (light grey). Credit: Carbon Brief analysis

The 32 countries that have identified some or all subsidies spend almost $270bn on nature-harming incentives annually, according to Carbon Brief’s analysis.

This is based on a tally of the figures for the most recent available year listed in countries’ national reports, in US dollars using conversion rates at the end of the given year and adjusted for inflation. The analysis also includes figures from other reports cited in the country submissions.

The $270bn reported in country submissions to date is “just the tip of the iceberg”, notes Eva Zabey, the chief executive of Business for Nature. The global figure could be as high as $1.8tn, according to a 2022 estimate from non-profit group, the B Team.

The figures identified by Carbon Brief are a “warning” that the “world is not moving fast enough” to tackle harmful subsidies, Zabey says, adding:

“The positive news is that some countries have shown it can be done and this should embolden others to follow suit…Subsidy reform should be treated as an economic necessity, not an environmental checklist.”

Harmful subsidies are expected to be among the key priorities at the upcoming COP17 UN nature summit, being held in Armenia in October 2026.

Subsidy target

There is no single definition of a “harmful” subsidy. (See: ‘Harmful’ subsidies.) 

The aim to identify these subsidies stems from target 18 of the Kunming-Montreal Global Biodiversity Framework (GBF) – the global agreement containing a series of goals and targets for nature.

Target 18.
Target 18 of the Kunming-Montreal Global Biodiversity Framework. Credit: UN CBD (2022)

Target 18 calls on countries to identify subsidies and other incentives that are harmful for biodiversity by 2025.

It also says that nations should “eliminate, phase out or reform” these subsidies in a “proportionate” way, reducing them by at least $500bn per year by 2030.

It says countries should first target the “most harmful” incentives, while simultaneously scaling up positive incentives for nature.

All 2030 targets in the GBF are global – with countries each expected to outline how they will contribute nationally. So far, 169 countries have submitted these national targets.

Only 38% of countries addressed the 2025 aim to identify harmful subsidies in their national targets “to some extent”, according to a draft version of an upcoming progress report.

Countries’ national reports do not “provide a sufficient basis to determine” whether the 2025 milestone was met, says the report, but available evidence “suggests” that it was not.  

‘Harmful’ subsidies  

There is no universally agreed-upon definition of a “biodiversity-harmful subsidy” – or how it differs from an environmentally harmful subsidy.

In general, “harmful” environmental subsidies impact humans’ surroundings, whereas those harmful to biodiversity directly affect species and ecosystems. Paul Elton, a PhD candidate at the Australian National University, tells Carbon Brief:

“If you were to do a study that focused on biodiversity-harmful subsidies versus one that focused on environmentally-harmful subsidies, there’d be a Venn diagram where a large percentage would overlap.”

A 2022 working paper on identifying subsidies harmful to biodiversity published by the Organisation for Economic Co-operation and Development (OECD) depicted biodiversity as a subset of the environment, with climate and air falling outside the scope of “biodiversity”.

However, the report also noted that climate change is one of the five key drivers of biodiversity loss, adding:

“As such, subsidies that lead to larger greenhouse gas emissions, for example, will also indirectly impact on biodiversity.”

Distinction between the “environment” and “biodiversity”, according to an oft-cited working paper on identifying and assessing biodiversity-harming subsidies. Credit: OECD (2022)
Distinction between the “environment” and “biodiversity”, according to an oft-cited working paper on identifying and assessing biodiversity-harming subsidies. Credit: OECD (2022)

Prof Jessica Dempsey, a political ecologist at the University of British Columbia, tells Carbon Brief that she would “absolutely” consider fossil-fuel subsidies to be biodiversity-harming – not only as a driver of climate change, but also because the extraction of fossil fuels can cause localised harms to biodiversity. She adds:

“I do think probably it is true that all harmful subsidies are not necessarily biodiversity-related. Some care in that is important, but subsidies to the sectors that are known drivers of biodiversity loss feel very obvious to me.”

Biodiversity-harming subsidies can be either direct or indirect.

Direct subsidies refer to government expenditures that go towards a project that harms nature, such as construction of a new gas-fired power plant. Indirect subsidies could include tax exemptions that encourage a certain behaviour, such as lower tax rates on fuels for agricultural machinery.

Subsidies in agriculture, fishery and energy sectors are most commonly deemed “harmful”, but damage can also be caused by support for forestry, infrastructure, transport, construction, water and other sectors.

One recent estimate of the global total of biodiversity-harming subsidies put the figure at $1.7-3.2tn annually. An estimate of environmentally harmful subsidies put the figure at $2.6tn.

Elton tells Carbon Brief:

“It’s useful to contextualise the $500bn ambition of the GBF against those global estimates of how big [the total] actually could be, because that underscores the fact that so far, you’ve only got a subset of nations reporting about $250bn by your analysis, which is only half of the [phase-out target].

“It’s a significant lack of accountability.”

The chart below compares the $2.6bn estimated value of harmful subsidies to the $500bn phase-out target set in the GBF and the value of the subsidies identified so far in national reports.

Chart showing biodiversity harming subsidies
Comparison of the harmful subsidies identified by countries in their national reports (light blue), the phase-out target for subsidies outlined in the GBF (medium blue) and a global estimate of environmentally harmful subsidies (dark blue). Credit: Carbon Brief analysis

Sectoral breakdown

Many subsidies can have both negative and positive impacts on biodiversity, according to the 2022 OECD working paper.

A subsidy on constructing dams for new hydropower can harm local biodiversity by disrupting water flows and flooding certain areas, for example. But it also reduces fossil-fuel dependence, lowering emissions and leading to a decrease in global warming.

Ronald Steenblik, a subsidies expert and co-author of the report estimating $2.6bn of harmful subsidies, tells Carbon Brief:

“What’s harmful is somewhat in the eye of the beholder.”

Most experts agree that a few sectors receive the bulk of the world’s biodiversity-harming subsidies: fossil fuels, agriculture and infrastructure, with much smaller contributions from other sectors, such as forestry, mining and fisheries.

Of the subsidies reported to the CBD, almost half were for the fossil-fuel sector, and around one-quarter for agriculture and fishing.

Chart showing that almost half of nature-harming subsidies go towards fossil fuels
Sectoral breakdown of identified subsidies. “Multiple” means a country either did not distinguish between sectors or reported one number encompassing several sectors. “Other” refers to specific sectors not named in the chart. Credit: Carbon Brief analysis.

Dempsey says it is “surprising” that mining “didn’t show up” in these figures. (Of the 32 countries that provided subsidy data, only one mentioned mining as an industry that received harmful subsidies.)

Limitations

One limitation of Carbon Brief’s analysis is the lack of standardisation of subsidy data.

The methodology underlying the national reports lists several definitions of environmentally harmful subsidies, adding:

“[T]here is no standardised, globally agreed methodology for assessing the value of subsidies…nor is there a single global dataset providing this information.”

It adds that it is “important” for countries to identify harmful subsidies “within their national context”. Steenblik says:

“When you get down into the details, you can have lots of arguments of where you draw the line. And, so, the big question on this spreadsheet is where countries drew that line.”

For example, China’s national report says the country has already identified all biodiversity-harming subsidies and reformed them entirely.

In Australia, a 2026 study – led by Elton from Australian National University – identified biodiversity-harmful subsidies worth $26.3bn over 2022-23, a number that amounts to just over 1% of the country’s GDP.

However, in its national report, Australia identified $155m worth of subsidies, largely in the agricultural sector. (The national report says that the identified agricultural subsidies are those that are “potentially most harmful to the environment”.)

Elton tells Carbon Brief that this discrepancy underscores the necessity of an independent assessment of harmful subsidies, “rather than this just being seen as a tick-the-box reporting exercise by officials in the environment department”.

When it comes to actually phasing out harmful subsidies, Dempsey says, focusing on the quality of the subsidy – and who benefits from it – is just as important as focusing on the numbers. She adds:

“If we don’t take this lens of understanding the beneficiaries and we only focus on the [numbers], we really risk having policy changes that then lead to increased affordability problems for everyday working people, and backlash.”

Methodology

Carbon Brief analysed national reports submitted to the CBD by 134 parties – 133 countries and the EU – to assess which ones had identified all of their biodiversity-harmful subsidies and therefore met the 2025 deadline.

The reports were submitted in 2026, with the analysis including those submitted by 1 July 2026.

The figures for each country can be found in this spreadsheet. More than three-quarters of reports did not list any figures.

To get the full tally for the amount listed, Carbon Brief used the figures for 2025 (or the nearest available year) and converted the local currency into US dollars, based on conversion rates in the given year using the currency exchange rates calculator from the US Treasury.

These figures were then adjusted for inflation to the year 2025. Numbers were rounded to the nearest $1,000.

In total, this amounted to $269,856,769,000 in subsidies across 32 countries.

Many countries listed the sector that each subsidy is going towards. Carbon Brief standardised these inputs using the following categories:

  • Agriculture and fishing
  • Energy
  • Forestry  
  • Fossil fuels 
  • Infrastructure
  • Transport 
  • Other
  • Multiple sectors

“Multiple sectors” was assigned when a country provided only a partial sectoral breakdown of their subsidies or none at all.

“Other” was selected to encompass sectors that were named more infrequently, including water, mining, tourism and construction.

The designations employed and the presentation of the material on the map in this article do not imply the expression of any opinion whatsoever on the part of Carbon Brief concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.

The post Analysis: 84% of nations miss deadline to identify ‘nature-harming’ subsidies by 2025  appeared first on Carbon Brief.

Analysis: 84% of nations miss deadline to identify ‘nature-harming’ subsidies by 2025 

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Cook Government must recognise risks posed by Woodside’s Scott Reef drilling plans

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SYDNEY, Monday 27 July 2026 — In response to an announcement that Woodside’s Browse to North West Shelf (Browse) Project was declared a State Significant Project by the WA Government, the following comments can be attributed to Senior Campaigner at Greenpeace Australia Pacific, Hannah Schuch:

“The WA Government must not ignore the significant risks clearly associated with Woodside’s plans to drill for gas at the pristine Scott Reef — to endangered marine life, our oceans, and our climate — all of which are valued and relied upon by Western Australians.

“The WA Environmental Protection Authority has already found Woodside’s plans to drill at Scott Reef would have unacceptable impacts on the environment without considering the climate impacts of 1.6 billion tonnes of carbon pollution associated with this disastrous proposal.

“Woodside’s gas drilling plans, including seismic blasting and carbon dumping in the heart of a precious ecosystem, pose potentially fatal risks to pygmy blue whales and genetically unique green sea turtles, and could cause a catastrophic oil spill.

“If the WA and federal governments are concerned with the prosperity of WA, they must reject Woodside’s nature and climate-wrecking proposal to drill for gas at Scott Reef.”

—ENDS—

High res images and footage of Scott Reef can be found here.

For more information or to arrange an interview, please contact Emma Sangalli on 0431 513 465 or emma.sangalli@greenpeace.org

Cook Government must recognise risks posed by Woodside’s Scott Reef drilling plans

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