April 4, 2022

expert reaction to Assessment Report 6, Working Group 3 (Mitigation), as published by the IPCC

The Intergovernmental Panel on Climate Change (IPCC) have published the Working Group 3 contribution to its Sixth Assessment Report (AR6).

This Roundup accompanied an SMC Briefing.

Professor Sir Jim McDonald FREng, President of the Royal Academy of Engineering, said:

“Today’s IPCC report makes it clearer than ever that we must accelerate progress against our climate change promises and move to decarbonise our economy and infrastructure.  Our current trajectory will lead to 3.2C warming by 2100 and we may not have time to respond to further warnings. While the current energy crisis is the first big challenge of the just transition, it brings with it the opportunity to pivot away from fossil fuels towards cheaper renewables and a low carbon energy system as well as to support vulnerable people through home energy efficiency retrofit. The report makes it clear that the cost of the transition cannot be an excuse for delay – the economic case made by the report authors is strong, highlighting that lower cost mitigation options could reduce global GHG emissions by at least half the 2019 level by 2030, while still allowing GDP to grow. All of this means that the solution to both the UK’s short term energy crisis and our long term climate challenge are the same; redoubling our efforts on mitigation policies that focus on shifting from fossil fuels to renewables, reducing demand, and retrofitting buildings.”

Prof Andreas Busch, Professor of earth sciences at The Lyell Centre at Heriot-Watt University, said:

“The recently published Working Group III contribution to the Sixth Assessment Report of the IPCC is again highlighting the need for and potential of carbon capture and storage (CCS) to limit global warming to 1.5°C or 2°C. The report clearly states its current limitations, especially economic and sociocultural barriers that need to be overcome to use the full potential of this technology. CCS is critical in decarbonising industry that is generally difficult to decarbonise without CCS, like cement and steel. The technology is currently far behind its modelled pathway and deployment needs to be accelerated to support CO2 emission targets in the future.”

Donna Lyndsay, Vice Chair of Space4Climate, Innovation Lead Ordnance Survey, said:

“We still just about have time to mitigate against the worst impacts of climate change by collaborating and driving forward climate services to support resource efficiency, infrastructure transition and resilience. Reliable, trusted data is critical to underpin no regret decisions to support mitigation and development pathways to net-zero emissions. With Space4Climate, Ordnance Survey is pioneering new ways to support mitigation strategies in urban and rural environments in collaboration with other UK Earth Observation expertise to ensure we maximise the insights Earth Observation and location data can provide are aligned to this challenge. An example of this is the recent heat data project where we took the heat data from the National Centre of Earth Observation in the UK was introduced to our public sector customer base. As a result we now have a series of case studies and new demand for the data across the UK to support mitigation. Another example is the creation of the peatlands observatory which supports the identification of peatlands in need of restoration”

Prof Michael Wilkins, Executive Director, Professor of Practice at Centre For Climate Finance And Investment, Imperial College Business School, said:

“The significant decrease in the cost of low and zero carbon technologies over the past decade, especially in solar and wind power, demonstrates that with the right policy incentives and economic frameworks, climate change mitigation can be financed at scale and relatively quickly. The same logic could equally be applied to new technologies being developed for carbon removal, such as direct air capture, where currently costs are prohibitively expensive for large scale development.”

Prof Stuart Haszeldine, Professor of Carbon Capture and Storage at the University of Edinburgh, said:

“Technologies are already proven to stop CO2 emissions with CCS. But oil companies continue to extract fossil fuel and walk away from the consequences. Governments must govern. Now is exactly the time. With multi tens of billions profits this year and next year, oil companies cannot plead poverty. Production licences for new fossil fuels in all countries must be combined with a producer responsibility obligation to balance the tonnes of carbon extracted with the same or more tonnes of carbon stored. No subsidy, just include the proper cleanup cost. That is Net Zero.”

Dr Shaun Fitzgerald FREng, Director, Centre for Climate Repair at Cambridge, said:

“The report today is extremely important, sobering, and governments must look very carefully at their response.

“Buried in the report is clause C11, ‘The deployment of CDR to counterbalance hard-to-abate residual emissions is unavoidable if net zero CO2 or GHG emissions are to be achieved. The scale and timing of deployment will depend on the trajectories of gross emission reductions in different sectors. Upscaling the deployment of CDR depends on developing effective approaches to address feasibility and sustainability constraints especially at large scales. (high confidence)’

“What this means is that the IPCC now says we HAVE to develop and deploy greenhouse gas removal schemes at scale if we want to stay below 1.5C. There is no choice. The issue is that funding for this needs to ramp up significantly and quickly. We need to look at not just land-based greenhouse gas removal schemes, but seriously investigate the oceans. We need to stop treating the oceans as a dumping ground in the same way we need to stop treating the atmosphere like that. But more than that, we need to tend to the oceans and undo a lot of the damage we have inflicted. One of the most damaging things we have done is to annihilate many whale species over the past few hundred years. Whales provide the function of recycling nutrients by feeding at depth and defaecating at the surface. These nutrients enable phytoplankton to grow, and this is critical for the carbon flux from the atmosphere to the ocean and ultimately to the ocean floor. Research is needed so that we can investigate approaches to bring back the whale populations, which will involve us tending and caring for the oceans rather than simply taking things from it or dumping things into it. Ocean based carbon dioxide removal is the most likely able to actually scale up in sufficient time to help us get to net zero by 2050.”

Dr Bipashyee Ghosh, Research Fellow in Deep Transitions and Transformative Innovation Policy Consortium, Science Policy Research Unit (SPRU), University of Sussex Business School, said:

“A key departure point of this IPCC report is its emphasis on systemic change.

“The report invites policymakers and investors to invest in accelerating systemic transitions following different pathways in different parts of the world.

“Accelerating urban mobility system transitions in the Global South means making walking, cycling and public transportation safe, comfortable, and aspirational for all income groups; supporting new social norms for reduced mobility demand, preserving and improving existing public transport and micro-mobility services; ensuring accessibility and affordability of these services for the marginalised population.

“It is good to see that using strong scientific evidence, this IPCC report invites decisionmakers to take a holistic view of the entire system, to focus on behaviours, values and norms and not just technologies or governance mechanisms, in order to transform our societies towards equitable futures.”

Prof Rob Gross, Director of UK Energy Research Centre and Professor of Energy Policy at Imperial College London, said:

“Another IPCC report and another call for urgent action. The report makes clear that immediate short term acceleration of low carbon energy is needed if limiting warming below danger levels is to stay feasible. On the upside they note the dramatic cost reduction in leading energy options, such and wind, solar and batteries. They also note that the pace of emissions growth is falling.

“But we are merely going in the wrong direction more slowly. This is one reason that the IPCC now say we will need not just net zero but to start to remove CO2 from the air. We cannot do one instead of the other but we have reached the point where it is likely that the humanity will need to do both to avoid dangerous climate change.”

Prof Daniela Schmidt, Professor at the School of Earth Sciences and the Cabot Institute, University of Bristol, said:

“A small minority of 10% of the people on this planet are producing between 34 and 45% of the global carbon emissions which is a staggering number. Per capita consumption is a strong expression of decisions of the few impacting the many which are often also the most vulnerability to climate change impacts. IPCC WGII has shown last month what the consequences of the failures to keen warming below 1.5C are. International cooperation needs to focus on combating climate change.”

Dr Jo House, IPPC lead author, Chapter 7: Agriculture, Forestry, and Other Land Uses (AFOLU); Lead on Monitoring, Reporting and Verification, and Socio-ecological systems CO₂RE; and Reader in Environmental Science and Policy, University of Bristol, said:

“It’s now or never, if we want to limit global warming to 1.5°C. Without immediate and deep emissions reductions across all sectors, it will be impossible,”

“The lack of global progress is depressing, it is literally killing people, and is felt in every country. However what gives me hope is the progress in some countries that have reduced greenhouse gas emission year on year for more than 10 years gives, and the fall in prices of solar, wind and battery technologies by up to 85. What gives me most hope though is the number of people who want to take action, who are calling on industry and governments to do something about it, and the industries and governments willing to work together to ensure sustainable, affordable choices that put planet and people first. If we can harness this hope into rapid action and investment we have the tools and technologies to avoid the most devastating effects”

Prof Nick Eyre, Director of the Centre for Research into Energy Demand Solutions, and Professor of Energy and Climate Policy at the University of Oxford, said:

“The report spells out the importance of how we use energy, identifying the potential to reduce energy demand by 40-70% by 2050. Together with a major expansion of renewables, reducing energy demand is central to delivering a stable climate.”

Prof Laura Diaz Anadon, Professor of Climate Change Policy, Department of Land Economy, University of Cambridge, said:

“We are not on track to limit warming to 1.5ºC, even though the average annual rate of growth in emissions has slowed over the past decade.  The report shows that average annual greenhouse gas emissions during 2010 to 2019 were the highest in human history: they were 12% higher in 2019 than in 2010 and 54% higher than in 1990, around the time when the IPCC process started. At the same time, during 2010-2019, the rate of growth in emissions from energy supply and industry more than halved, while the growth in emissions from transport remained roughly constant. It also shows that, globally, the richest 10% households contribute around 40% of global consumption-based emissions, with the bottom 50% contributing less than 15%, so we have very uneven emissions patterns.”

“This report shows new, clear and increased evidence of climate action. This evidence includes the fact that at least 18 countries have achieved sustained production- and consumption- based CO2 emissions reductions for longer than 10 years, and sustained large decreases in the cost of key technologies for decarbonisation, including solar PV, on- and offshore wind and lithium-ion batteries. At the same time, an increasing range of policies and laws have resulted in improvements in energy efficiency, accelerated deployment of renewable energy, and reduced rates of deforestation.”

“The report shows there are options available in all sectors to at least halve emissions by 2030 at USD100 tCO2-eq or less. For instance, on the demand side, by 2050, a combination of effective policies, improved infrastructure and technologies leading to behavioural change has the potential to enable reductions in GHG emissions by 40-70%. On the energy sector, which accounts for 34% of emissions, the report finds that we will need major transitions. Limiting global warming to 1.5ºC or 2ºC would mean premature shut down of coal related infrastructure by 2030 and oil and gas by 2050, among other changes.”

“The next few years will be critical to improve our chances of success. Unless there are immediate and deep GHG emissions reductions across all sectors, 1.5ºC is beyond reach. The report found that policy packages, such as within an energy system and economy wide packages, are more able to support wider transitions and achieve systematic change than individual policy instruments on their own. Many regulatory and economic policy instruments have already been deployed resulting in emissions reductions and instrument design can help address equity and other objectives. Similarly, low emission technological innovation is strengthened by combining technology push policies and investments (such as for scientific training, R&D and demonstration) and tailored demand pull policies (e.g., standards, feed in tariffs and taxes), which create incentives and markets.  In short, this new report shows a growing amount of evidence on the role of a wide range of policies on emissions reductions and innovation.  At the same time, to limit warming to around 2ºC, GHG emissions would need to peak before 2050.  This new report also found that carbon dioxide removal is unavoidable to achieve net zero emissions.”

“This report is very clear about the urgency and scope of the challenge, but also the fact that there is important evidence of action, of what makes policies effective, and the need to consider equity and justice.”

Peter Taylor, Professor of Sustainable Energy Systems, University of Leeds and the UK Energy Research Centre, said:

“There are five clear messages from the IPCC WG3 report in relation to decarbonising industry. Firstly, that achieving net-zero CO₂ emissions from industry is possible. Secondly, that this will be a complex process in which demand-side measures, such as energy and materials efficiency, will be important – alongside new fuels and technologies, such as hydrogen and carbon capture and storage. Thirdly, that many of the promising low-to-zero emission technologies need further research, development and demonstration to make them commercially viable, but that any increased costs to consumers will be minimal. Fourthly, that more attention needs to be paid to the role of industry in global and national economy-wide scenarios and finally that more focus should be given to bring forward the policy packages that will deliver change, taking account both of societal impacts and the role of international competition, co-operation and co-ordination.”

Dr Steve Smith, Executive Director, CO₂RE; and Oxford Net Zero, University of Oxford, said:

“This is the first IPCC report to state clearly that carbon dioxide removal (CDR) is needed to achieve our climate targets. The report shows there are many ways to remove carbon – from tree planting and soil restoration to capturing and storing CO₂ from bioenergy facilities, and even direct air capture machines – just like there are many ways to cut emissions.

“It might sound crazy to talk about CDR when we are still putting it up there at record rates. But the reality is that if we’re serious about pursuing a robust and affordable set of actions to get to net zero by 2050, then CDR is in the mix. And that means starting now.

“With carbon removal getting lots of the headlines, it’s crucial to remember we won’t stop climate change without all the other stuff in the IPCC report: cutting energy waste, cutting fossil fuels if the carbon isn’t captured and stored, better diets, and not cutting down forests. To put things into perspective, the IPCC pathways suggest about 3-4 billion tonnes of removals to achieve net zero CO₂ emissions, 8 billion at a real stretch, while CO₂ emissions are cut by something like 40 billion tonnes.”

Dr Rob Bellamy, Lead on Responsible Innovation and Societal Engagement, CO₂RE; and Lecturer in Climate and Society, University of Manchester, said:

“The debate is no longer about whether or not we should use CDR, but what CDR, how much, where and so on. Key to answering all of these questions in a responsible way is involving wider society in decision making. CDRs are sociotechnical systems – you have the bits of kit, but they will simply not work without people, procedures, policies, governance and so on. Society needs to be a part of the conversation on which approaches to take forward, how to incentivise them if they are taken forward, and ultimately how to govern them.”

Prof Jason Lowe, Head of Climate Services at the Met Office Hadley Centre and reviewing editor on the Working Group III report, said:

“The IPCC publishes these series of assessment reports about every six years, with the last in 2013/2014.  If we are to maximize the chances of limiting warming to 1.5C then it is clear from today’s report that the world needs to reach peak greenhouse gas emissions within the next handful of years. If meaningful action to curb emissions is delayed until the next reporting cycle towards the end of the decade, we may have missed the opportunity to avert some of the most serious climate impacts.”

Dr Andy Wiltshire, Head of Earth System and Mitigation Science at the Met Office Hadley Centre, said:

“Climate change remains one of the major threats to human wellbeing and security. Rapid reductions in emissions of greenhouse gases remains the only way to reduce this risk.

“The recent set of IPCC reports bring a message of hope, that through climate resilience development combined with protection and regeneration of our environment we can simultaneously mitigate the worst risks, adapt to the inescapable impacts of climate change whilst improving human wellbeing and sustainability. To realise this potential requires urgent action to mitigate emissions and set us on a sustainable path of development.”

Prof Jon Gibbins, Professor of Power Plant Engineering and Carbon Capture at the University of Sheffield, said:

“It is progress to see that the entirely self-evident statement that “the deployment of CDR to counterbalance hard-to-abate residual emissions is unavoidable if net zero CO2 or GHG emissions are to be achieved” has been included in this round of IPCC reporting.

“But hopefully a more realistic position will become the norm by the next round, that carbon dioxide removal (CDR) can, and should, be used to indirectly capture and securely store any and all CO2 emissions that are most effectively addressed in this way.  It also very urgently needs to be recognised that new fossil fuel facilities do not necessarily have to lock in future GHG emissions, provided that carbon capture and storage (CCS) readiness becomes an integral part of new infrastructure developments. 

“With a suitable choice of location, and some very low cost provisions in the original plant, CCS will then be able to be retrofitted later with minimal cost and reduction.”

Prof Stephanie Henson, Principal Scientist at The National Oceanography Centre, said:

“The third report from the IPCC focuses on how human actions could mitigate climate change and builds on the previous two reports that detailed the impacts of climate change on humans and the evidence of climate change throughout the Earth system. This report emphasises that humanity is currently not on track to limit warming to 1.5C, but that it is still possible to halve emissions by 2030 by using existing technologies and options. For example, moving rapidly to non-fossil fuel sources of energy, improving transportation options, minimising waste in industrial manufacturing or restoring biodiverse habitats. Ambitious mitigation efforts require coordination across government, but also buy-in from global citizens to make changes to how they travel, shop and live.”

Professor Mark Maslin, University College London, said:

“After two weeks of negotiations 195 countries have agreed the summary text, just 4 hours before the release of the IPCC Mitigation report. This is because of the controversial nature of this report which clearly shows that fossil fuel production and use must be phased out as soon as possible.  This has huge consequences for any country whose economy relies heavily on fossil fuel production.  Bottom line is that the global carbon emissions must be cut by at least 43% in the next 8 years if we are to have any chance of keeping the world to just 1.5 C warming . This means stop using fossil fuels now. The IPCC Mitigation report though pessimistic about the likelihood of cutting emissions quick enough, is very positive that we have all the technology, we can easily shift the social-cultural demand for energy and we can easily build all the new infrastructure needed.  We just need the political will to go ahead and save our planet while ensuring billions of people are lifted out of energy poverty and food insecurity.”

Prof Michel Kaiser, Heriot-Watt University’s Chief Scientist and Professor of Fisheries Conservation at The Lyell Centre, said:

“The IPCC report is the clearest to date on the threat of delaying serious climate change mitigation policies.

“The UK has made huge strides in decarbonising energy and looking at nuclear power makes perfect sense. We should revisit tidal power in the form of coastal lagoons and barrages given our need to makes ourselves less reliant on externals sources of power.

“However, none of this will be effective without investment in appropriate infrastructure to keep pace with a shift to electric powered vehicles, and appropriate policies that ensure that new build properties are fit for a net zero future.”

Eliot Whittington, Director of Policy, University of Cambridge Institute for Sustainability Leadership (CISL) said:

“This report should be read as a how-to guide for any decisionmaker interested in navigating towards security, success and a sustainable environment over the next few decades. It spells out from the first line that a prosperous future economy can and must go hand in hand with the effort to decarbonise. It makes it clear we have no time to spare, and need to urgently transform words into actions. The next decade will be decisive.

“It also is clear on the toolkit for action – we must see renewable energy, efficiency, electrification and nature restoration take off at transformative scales. We must see fossil fuels quickly phased out from the economy. We will also need to explore and develop new carbon dioxide removal approaches which will be risky but essential to achieve the goals of climate stability.”

On business

“The new IPCC report is clear that the next decade can and must be transformative – taking the world from a trajectory of ever-increasing carbon emissions to one where they have halved. This will affect every business and every sector, and leading businesses are the ones working out what it means for them and their context and working hard to shape a future they can be part of. Catastrophic climate impacts represent threats to our society, our economy and our environment in a way that will be existential for many businesses as well. A growing number of businesses have set net zero goals and started to deliver the innovation and transformation required by this – but a much larger set of businesses need to take action and embark on this journey – delivering not empty promises but real commitments of action.”

On the UK

“Later this week we should see a new British Energy Strategy responding to the transformed context caused by the invasion of Ukraine. The last IPCC report last month clearly showed UK security can only be assured in a world that acts on climate change and this one shows that our best economic future including our best positioning for economic advantage in new and growing industries lies in the zero carbon energy transition. The new strategy will need to address the immediate challenges of high energy costs and transformed geopolitics in a way that accelerates a path towards long term prosperity and a new net zero future.”

On the EU

“With war on its borders the EU is at a fundamental crossroads as it navigates a new geopolitics and a new set of challenges to its energy supply and security. The new IPCC report has provided a clear routemap for the best path forward – accelerating the path towards energy independence through renewables, electrification and energy efficiency among other measures. As Europe takes the next steps with its REPower EU plan and its Fit for 55 package of policies it should take the insights from this report to heart and step up ambition.”

Adrian Bull, BNFL chair in Nuclear Energy Systems at The University of Manchester’s Dalton Nuclear Institute, said:

“To get close to the deep emissions reductions necessary, major countries need every form of low carbon generation they can muster. Today’s report highlights the fact that research and innovation can play a crucial part in bringing the costs of low carbon power generation down – but we can’t afford to wait. Nuclear – the only proven and practical way of delivering vast quantities of low carbon power 24/7 in many countries – must have a role to play alongside wind, solar, tidal and other renewable options, and this must include advanced reactor designs as well as the large, traditional reactors we’re used to. Governments in countries like the UK are finally making the necessary commitments to help this to happen but there is no time for further delays.”

Dr Andrew Wright, Reader in Building Engineering Physics at De Montfort University, said:

“This report reminds us of the urgency to move to zero carbon. Meanwhile, rocketing fuel prices are hitting household budgets hard. A collective effort is needed between government, industry, and the public to improve insulation and shift towards low carbon systems like heat pumps and expand renewable energy. According to the IPCC, existing and future buildings could approach net zero emissions by 2050 – but only with effective implementation of sufficiently ambitious policies.”

Prof Klaus Dodds, Professor of Geopolitics at Royal Holloway, University of London, said:

“The IPCC’s Climate Assessment Report is a chilling reminder that disruption and injustice is forthcoming for planet Earth. Moving to a post-fossil fuel future is an urgent necessity but how we get there depends on reconciling finance, geopolitics, sovereignty, security and technology. Tough yet fair choices need to be made now.”

Prof Myles Allen, Professor of Geosystem Science, University of Oxford and Director of the Oxford Net Zero initiative, said:

“Once again, the fossil fuel industry has played a blinder. At a time of rising carbon dioxide emissions, record profits, and a rush to license new oil and gas fields, all the headlines around the latest IPCC report are about how “we” are going to have to change our behaviour and pay to scrub carbon dioxide back out of the atmosphere. How about “they” – the industry – need to stop selling products that cause global warming – by safely and permanently disposing of all carbon dioxide generated by their activities and products by 2050? This would, of course, increase their costs – but gradually and predictably over the next 30 years by slightly less than their profits have increased over the past 9 months. Of course, the IPCC can’t say this, but that doesn’t make it any less true.”

Dr Robin Lamboll, Research Associate, Center for Environmental Policy, Imperial College London, said:

“The latest report from the IPCC shows that while we’ve made progress towards climate goals, there is still a huge gap between current action and the actions needed to limit warming below more damaging levels. Although growth in renewable energy, efficiency and electrification is displacing growth in fossil fuels, it’s too slow and we cannot afford to simply wait for this to happen on its own. The report also assesses the relationships between sustainable development goals and climate action, showing that many types of climate action can also directly help the world’s poorest, who are generally least to blame but most harmed by climate change.”

Professor Mike Meredith, oceanographer and Science Leader at the British Antarctic Survey, said of the latest IPCC report:

“Even in these times of political turmoil and a global health crisis, climate change remains a critical and urgent issue that needs addressing by all countries. Recent reports from the UN’s Intergovernmental Panel on Climate Change have given updates on the dramatic progression of global warming, and what the current and future impacts of it will be. Their messages are very stark, and it is clear that something must be done. But what?

“That is where IPCC Working Group III comes in. This group has assessed the effectiveness of different approaches to tackling climate change, and what might be the best routes forward.  They show that it is now overwhelmingly clear that urgently slashing greenhouse gas emissions is absolutely critical – any proposed approach to dealing with the climate crisis that doesn’t involve this is doomed to failure. Some scientists and policymakers believe that, challenging though this will be, it will still not be enough, and have been advocating for the active removal of CO2 from the atmosphere as well.

“There are many different ways that this could be done, with some “natural” solutions, such as planting more trees or restoring seagrass meadows. Other methods are more technological, including building large machines to actively suck CO2 from the air. Some proposed techniques are very controversial, such as fertilising the ocean to stimulate plankton growth, or purposefully brightening clouds to reflect more heat from the sun back into space. Even if these methods could be deployed on a big enough scale to make a significant different to climate, there are concerns that some of them could trigger unforeseen feedbacks on the climate system or damage to the ecosystem. If we get these wrong, we could get them very, very wrong. The work of IPCC is thus crucial: by collating and assessing all of these concepts, along with the connected societal and economic aspects, and providing the world’s governments with an overview of what is needed, what might be feasible, and what the risks are. This is critical in determining how we address the climate crisis, both in the immediate short term and over the next several years.”

Dr Joana Setzer, Assistant Professor at the Grantham Research Institute on Climate Change and the Environment at the London School of Economics and Political Science, and Contributing Author on Chapter 13 of the new IPCC report, said:

“This report shows that we will need to rely increasingly on the courts to hold governments and companies to account, and ensure that they act in ways that are more consistent with the pledges they are making domestically and internationally. The report highlights the growing importance of climate litigation, and our research indicates that the number of cases is growing around the world, helping to increase both ambition and accountability.”

Prof Simon Lewis, Professor of Global Change Science, University College London, said:

“Despite the triple crisis of the war in Ukraine, the pandemic, and rising inflation, the world’s governments have signed-off the definitive common guide to tackling climate change. This report shows how countries can meet the obligations they signed in Paris in 2015 and reaffirmed in Glasgow late last year. They have no excuses now. The scientists involved have done an incredibly impressive job in getting this over the line in the circumstances.”

Bob Ward, policy and communications director at the Grantham Research Institute on Climate Change and the Environment at the London School of Economics and Political Science, said:

“This new report lays out starkly how much trouble the world is now in because governments have been too slow to recognise and respond to the threat from climate change driven by greenhouse gas emissions. The previous IPCC report published in February was very clear about the huge scale of the potential impacts on lives and livelihoods worldwide if global temperature rises by more than 1.5 Celsius degrees. But this new report shows that warming will likely exceed 1.5 Celsius degrees by about the middle of this century, and the best we can now aim for is to bring down the temperature before the end of the century through natural and artificial means of removing carbon dioxide from the atmosphere. This means we must accelerate the development and deployment of carbon dioxide removal, even though we are not yet sure of its feasibility and cost at large scale.

“In any case we must also speed up the deployment of zero-carbon alternatives to fossil fuels, the cost of which have fallen spectacularly over the past few years, as this report shows. Europe has learned over the past few months that the dependence on fossil fuels also threatens energy security and affordability.”

Dr Hywel Davies, Technical Director of the Chartered Institution of Building Services Engineers, said:

“This assessment report must convince policymakers and commentators in the UK of the need for urgent, sustained and significant cuts in energy use and not just in emissions. It illustrates the imperative of tackling operational and embodied carbon emissions in our cities and the urgency of moving away from fossil fuels wherever possible. And finally it shows the scale of investment needed in the skills and knowledge to deliver a net zero carbon built environment.”

Prof Michael Wilkins, Executive Director, Professor of Practice at Centre For Climate Finance And Investment, Imperial College Business School, said:

“The significant decrease in the cost of low and zero carbon technologies over the past decade, especially in solar and wind power, demonstrates that with the right policy incentives and economic frameworks, climate change mitigation can be financed at scale and relatively quickly. The same logic could equally be applied to new technologies being developed for carbon removal, such as direct air capture, where currently costs are prohibitively expensive for large scale development.”

Dr Kate Simpson, Research Associate in housing adaptation and retrofit, School of Design Engineering at Imperial College London, said:

“I am glad to see the acknowledgement that energy efficiency policies can contribute to 42% of the decarbonisation of the global building stock, with particular mention to the skills and supply chains required to achieve this. The recognition that ‘2020-2030 is critical for accelerating the learning of know how…ensuring the flow of finance and developing the skills needed’ should be a call for more urgent action for governments across the world. A recent special issue focused on the capabilities required to decarbonise buildings acknowledged the role of the micro-enterprise practitioners across the construction sector, contributing to 77% of the industry and those most frequently involved in upgrading domestic building stocks (Simpson et al., 2021). Policies must work to meaningfully engage this sector and build on their existing capabilities, while connecting them with and enabling householders to decarbonise and improve affordable comfort in their homes, while reducing reliance on fossil-fuelled heating and cooling systems.”

Declared interests

Dr Robin Lamboll: “IPCC corresponding author, otherwise no conflicts of interest.”

Prof Myles Allen: “No conflicts of interest.”

Bob Ward was an observer at the plenary approval session for the Summary for Policymakers of IPCC Working Group III’s contribution to the Sixth Assessment Report

Prof Simon Lewis: “No interests to declare.”

Prof Jon Gibbins is Director of a virtual research centre covering all aspects of CCS

Prof Nick Eyre was Review Editor of Chapter 5

Prof Mark Maslin: “no conflicts.”

Prof Laura Diaz Anadon is a Lead Author on Chapter 16 of the IPCC WG3, and also a member of the new European Scientific Advisory Board on Climate Change

Prof Rob Gross: “none to declare.”

Dr Andrew Wright: “No interests to declare.”

Prof Daniela Schmidt was a WG2 author.

Prof Peter Taylor: “I have no declarations of interest.”

Prof Stuart Haszeldine: “Research funding from NERC and EPSRC. No commercial or business conflicts.”

Dr Bipashyee Ghosh is a contributing author for Chapter 5 of the IPCC report.

No others received.