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The International Panel on Climate Change published its report into Climate Change and Land. Covering topics such as; Desertification, Land Degradation, Sustainable Land Management, Food Security, and Greenhouse gas fluxes in Terrestrial Ecosystems.
Dr Jessica Davies, Senior Lecturer in Sustainability, Lancaster University, said:
“Sinking carbon from the atmosphere into the land with trees or soils isn’t a replacement for rapidly reducing our fossil fuel use, so it isn’t a silver bullet. But if we want to limit warming to 1.5 or 2 degrees it is an essential part of the solution. To avoid the worst consequences of climate change, we need to not only reduce our fossil fuel emissions, but also reduce land use emissions and even achieve negative emissions. Tree planting or increasing carbon stocks in soils are a relatively natural means for achieving negative emissions, that in many cases provide other benefits as well. This report highlights that restoring soils and vegetation can help with climate change whilst also delivering other benefits for biodiversity, food production and water resources.
“Vegetation and soil cannot capture endless amounts of carbon. If we’re restoring soils or ecosystems to sequester carbon, then as those soils recover or plants approach maturity the amount of carbon added each year will slow down – but at that point we will have stored carbon in the land and we can maintain that store.
“This report strongly highlights that there are also many other benefits to taking a land-based approach to mitigating climate change – for example, if we’re restoring soils, we increase the carbon stored helping with climate change, but we may also get food production benefits from increased soil fertility, biodiversity benefits and improved soil water storage or infiltration that can help protect us from floods and droughts.”
Prof Corinne Le Quéré, Member of the Committee on Climate Change, and Professor of Climate Change Science, University of East Anglia, said:
“The IPCC has issued a stark warning: the way the world uses its land must change to limit global warming to 1.5°C. That includes rethinking how food is produced globally, our food choices, and how land is managed. Rapid action is needed – delay risks serious impacts including desertification, further degradation of land, and potential disruption to the global food supply. The IPCC’s findings chime with our advice to Government: the UK needs to reduce food waste, promote healthy diets, and use land sustainably, including planting more trees and restoring degraded soils. All of these steps will help to improve people’s lives whilst reducing the harmful emissions which cause climate change.
“In early 2020, the Committee on Climate Change will publish a comprehensive assessment of the policies needed to ensure land in the UK is used sustainably and contributes to the UK’s commitment to reduce its emissions to ‘net zero’ by 2050.”
Prof. John Crawford, Head of the Integrated Solutions Lab, Rothamsted Research, said:
“The future risks we face are highly interconnected, often in ways that make it difficult to predict outcomes. However, complexity should not be conflated with complicated. As the report highlights, these interconnections mean that solving a few problems in a coordinated way can mitigate a far larger number of additional connected risks.
“For example, increasing soil health will results in significant reductions in atmospheric carbon, store more water for food production, increase the efficiency of crop nutrition and make our production systems more resilient to climate shocks and food commodity price fluctuations. Embracing complexity actually makes it easier to identify and implement solutions. However, it also means that there is no single intervention and solutions require that we break down traditional barriers between scientific disciplines and businesses in such a way that we can coordinate our response across the whole food chain.
“Again, there is new hope because agriculture is on the brink of a technology and data-enabled revolution that will give us access to almost real time information about agriculture and its environmental impact. This will enable more sophisticated mathematical analysis such as has been used in physics for nearly 300 years to solve complex problems in astronomy, engineering and to a lesser extent in medicine.
“The single most important message from this report is that the food system has been broken by a world view that ignores the interconnections in that system, and that has produced unintended consequences that will have dire consequences for our future wellbeing if nothing is done. Reconnecting the food system by acknowledging these interconnections, will allow new levels of optimisation at the scale of the whole system (rather than its parts). It will allow us to identify fewer and more synergistic interventions that reduce a far larger number of risks.”
Prof Colin Campbell, Chief Executive, James Hutton Institute, said:
“We welcome the report. Its findings are clear and stark. How we manage our land, and the use of our land needs to change. We need transformational change, not just incremental changes. In northern temperate regions, this means we need to rest land more frequently from intensive cultivation techniques and regenerate and restore habitats that sequester carbon. The importance of peatlands and forestry is clear but converting land under current agriculture practises needs to acknowledge the cultural barriers and ‘transition’ land uses such as agroforestry have a role to play here because they incorporate the benefits of both and allow farmers to adapt their systems towards higher C sequestering systems. It’s good to see an acknowledgement of the importance of understanding human behaviour and the choices we all make but these areas of social science are still under-resourced at a time when we need much more social science working together with the natural sciences to solve the climate change challenges.
“Food waste is an area we can do a lot better. Some estimates put food waste due to pest, disease and deterioration at 30% and clearly, this has a big impact. So, producing crop varieties with resistance to disease and pests and also crops with longer shelf-life will help a great deal. Also, new technology such as indoor vertical farming eliminates pests and disease by growing crops in a high hygiene environment without the need for pesticides. Such systems are also climate-proof and reduce food miles and with more uniform and consistent food less produce is rejected so Indoor Systems will also dramatically reduce food waste.”
Dr Joeri Rogelj, Lecturer in Climate Change, Grantham Institute, Imperial College London, said:
“This latest IPCC report takes a deep dive in how land can contribute to solving the climate change challenge. It strengthens the findings of last year’s 1.5°C Special Report, while our understanding of what needs to be done to keep warming to 1.5°C remains unchanged. There is no silver bullet and ambitious, transformational action in all sectors is required in the next decade. This new report, however, clarifies what future role the land sector could play.
“There are some great opportunities for climate and development, but also potential disastrous outcomes if things are not done right. Opportunities are there where using the land for climate action contributes positively to eliminating hunger or eradicating poverty – think better managing pastures and forests making them more resilient, increasing the amount of carbon retained in soils thus making them healthier, or making our food system more efficient by increasing productivity and cutting out food losses and waste. There are also pitfalls when betting on land and nature to take up too big a role: zealously relying on excessive amounts of bioenergy, carbon-dioxide removal or nature-based solutions to get to net zero is a risky and unwise strategy. When badly implemented, these measures can result in further land degradation or counteract sustainable development. Moreover, the climate benefits of measures like rewilding or other nature-based solutions cannot be taken for granted. The carbon stored in natural systems can easily be returned to the atmosphere with a sequence of extreme weather events like the heatwaves we have been experiencing recently.
This report thus provides new building blocks for a smart approach to climate action, in which land and nature are not used as out-of-jail cards for emission reductions from power stations or industry. The health and sustainable management of land and natural systems is both an aim and a means to ambitious climate action in the next decade.”
Prof Jane Rickson, Professor of Soil Erosion and Conservation, Cranfield University, said:
“The IPCC Report presents the latest evidence on how global warming and associated climate change (CC) phenomena have significant impacts on global land resources (in particular soil, water and vegetation), which affect peoples’ health, livelihoods and wellbeing. The Report demonstrates that CC induced land degradation from more frequent and extreme weather events is hindering progress towards the UNs’ Sustainable Development Goals, including No Poverty (SDG 1), Zero Hunger (SDG 2) and Sustainable Cities and Communities (SDG11). Finite natural resources are under increasing competition from a growing global population, often leading to irreversible land degradation processes such as soil erosion, compaction, loss of organic matter, loss of biodiversity, landslides and salinisation. The Report also recognises that land degradation (such as draining of peatlands and soil erosion) aggravates climate change, leading to an escalating crisis. The Report acknowledges that the extent and severity of climate change effects are likely to vary over space and time (as will the ability of the environment and society to control, mitigate or adapt to these effects).
“The ‘call for action’ in D3 is very convincing: urging politicians and land managers to implement policies and practices that will reverse, mitigate and/or adapt to the unprecedented rates of global warming that are causing the current climate crisis. The Report lists practical and cost-effective land management responses to the impacts of climate change on land that will bring co-benefits in the short- and long term. Uptake of these measures needs adequate extension and advisory services, training, access to resources and more secure land tenure. Devising national policy that can be implemented locally is challenging. The Report acknowledges the need for mechanisms to incentivise land managers (and others involved throughout the agriculture and forestry supply chain) to mitigate or adapt to climate change in the short term (often incurring financial costs to their businesses), that will bring longer term benefits (to the benefit of society). It also recognises that mitigation and adaptation measures such as introducing new crops / changing land use and management will have economic, social, ecological and environmental consequences that must be understood before implementation.
“The Report warns that CC induced land degradation is already beyond control in places (e.g. coastal erosion due to sea level rise, thawing of permafrost and loss of crop yields due to soil erosion). Delay in action will increase the need for more widespread action in the future; will limit the number of options available; and will reduce the effectiveness of those options in adapting / mitigating the adverse effects of CC on land.”
Dr John Lynch, Postdoctoral Researcher, Department of Physics, University of Oxford, said:
“Land-based carbon storage through, for example, forestation or soil carbon sequestration, can only provide part of what is required to mitigate climate change, because the total sequestration capacity of the land is limited to only a fraction of the CO2 we have emitted1. And the challenge is becoming ever greater as fossil fuel emissions continue to increase2. Nature-based approaches can still play an important role in climate change mitigation and adaptation, and provide a range of wider environmental and social co-benefits; but as the report highlights, we still need to rapidly decrease our emissions3.”
Prof Mark Maslin, Professor of Climatology, University College London (UCL), said:
“The IPCC climate change and land report demonstrates the huge impact humanity is having on the land. Over 70% of the ice-free land on Earth is directly affected by humans. We currently use nearly a third of the land productivity for food, feed, fibre, timber and energy. Our use of the land is a major source of greenhouse gases contributing to climate change.
“The report clearly shows that though massive reforestation and rewilding are important, but they are no substitute for rapid cuts in greenhouse gas emissions. If the climate is to be stabilised at 1.5C then global carbon emissions must be reduced to zero by 2050 and then negative carbon emissions driven by reforestation must occur for the rest of the century.
“The report shows that there are considerable win-win solution through managing our land better – from increasing food security, reducing deforestation, ameliorating local changes in climate and absorbing greenhouse gases.
“This report is a wakeup call to the World that we must manage how we use the land as we rely on the land for everything from our food, our water, our resources and our protection. Climate change is having a significant effect on the land and as well as making massive cuts in global carbon emissions we must reforest, rewild and switch to sustainable agriculture to offset and adapt to the changes that are already occurring.
“This report should make everyone deeply concerned about the vulnerability of our land. But it provides hope that there are many holistic and sustainable land-based solutions we can use to combat climate change and provide sustainable safe and secure future for humanity. These will require international cooperation and a willingness to manage the land for everyone’s benefit including future generations.”
Dr Jessica Thorn, Research associate and African Women in Climate Change Science Fellow. University of York, said:
“One of the most serious points raised in the report is that climate change will likely increase environmentally-induced migration both within countries and across borders, leading to an increase in so-called climate refugees. Moreover, it has clear implications for those living in growing informal settlements, which are often located in hazardous zones. Another key finding is that the frequency and intensity of droughts are projected to increase particularly in southern Africa, often followed by more extreme rainfall events. This was shown in May of this year, for example, when the Namibian government declared a national state of emergency after six years of drought. We should not underestimate the potential implications of what is described in the report as “cascading risks” (A5.3), such as water scarcity, food insecurity, vegetation loss, and wildfires. What is perhaps even more striking, is that Asia and Africa are projected to have the highest number of people vulnerable to increased desertification. Land degradation resulting from the combination of sea level rise and more intense cyclones is projected to jeopardise lives and livelihoods in cyclone prone areas – as evidenced by the recent Cyclone Idai in Mozambique.
“Overall, the report illuminates the need to take urgent and serious measure at all levels of governance, to ensure the future sustainability of the resources and services that support livelihoods and human-wellbeing.”
Dr Christian Reynolds, Associate Director, Institute for Sustainable Food, said:
“This report is a line in the sand that should push us towards a food system that benefits our environment, instead of damaging it. Crucially, the IPCC has confirmed that food waste contributes between eight and 10 per cent of global greenhouse gas emissions and animal agriculture accounts for half of all emissions from our food system. So, if we can make a start on reducing food loss and waste and shift our diets to smaller portions of meat and more sustainable farming methods, this more efficient approach will make a huge contribution to efforts to prevent runaway climate breakdown.”
Prof Karen Johnson, Professor in Environmental Engineering, Durham University, said:
“I agree with the report that we need to consider land when we develop sustainable bioenergy resources. But at the moment we are not doing this in the UK. The UK’s Renewable Heat Incentive is incentivising industry to direct organic wastes for bioenergy such as anaerobic digestion to make biogas and ultimately electricity.
“But this has potentially significant negative implications for soil health as it reduces the carbon content of those wastes some of which were previously returned to land. This is in direct contradiction to the Paris Climate change agreement which we signed in Dec 2015 which says we should add more organic matter to soil (see Nature 2019)”
Dr Jeff Price, Senior Researcher, University of East Anglia, said:
“Knowing how the process works, I suspect that there have been actions on the parts of some Governments in how the statements have been framed. There seem to be cases where what seems like two different statements have been merged when they should not have been. I was surprised at the number of low confidence statements (level of confidence in the statement being scientifically valid) included as the SPM typically aims for high confidence statements with the occasional medium confidence statement thrown in.
“I was disappointed at how poorly biodiversity and species risks to climate change were captured in this document. The mentions of these are largely general and not specific. There is good recognition that changes in land use will impact biodiversity, but there is not adequate consideration of how climate change will impact it as well. As far as I can see from this summary, biodiversity does not figure prominently at all – or is captured generically as ecosystem health. One of the principle ways in which species have responded to past climate changes is by shifting their ranges. While the report recognises that climate mediated range shifts are already occurring there is little consideration of the role restoration and other land management practices play in species adaptation to climate change through the creation of connectivity (bigger and more joined up ranges).
“There are other examples of areas in the summary where biodiversity has not been considered as much as it should, for example, if trees are planted in what was traditionally non-treed landscapes then there may be mitigation benefits but large impacts on biodiversity. There also appears to be no consideration of the impacts of BECCS on biodiversity as far as I could see, yet there is a large body of literature on this. Furthermore, while sustainability is often mentioned in the summary, and food security is a major emphasis, the same cannot be said for the potential conflict between bioenergy and biodiversity which is largely missing.”
Prof Achim Dobermann, Director, Rothamsted Research, said:
“Better land management that is smarter and takes into account its variety of uses is vital – not just because it decreases competition for land, but because it can potentially help eradicate poverty and fight climate change.
“However, I don’t think that we can afford to take good agricultural land out of production because that would make it much harder to achieve and sustain food security under known climate change threats and the rapidly expanding global population. Because the ultimate driver of most land use change is to create more farmland, sustainable intensification of our current agricultural areas can be the only solution to this problem.
“Many of the interventions needed for this require accelerated R&D, a wider adoption of tailored technologies and better management practices to have any sort of impact within the next 10-20 years. That, to me, is the real challenge and it requires far greater and long-term political commitment and investment in every country.”
Dr Geraint Evans, Freelance energy engineer specialising in biomass, bioenergy, biofuels and CCS, said:
This IPCC report highlights the need for bioenergy and BECCS – BioEnergy with Carbon Capture and Storage – as part of an overall strategy to limit global warming to 1.5°C or well below 2°C. This compliments the findings of the UK’s Energy Technologies Institute (www.eti.co.uk) and the Government’s advisors, the Committee on Climate Change (CCC). Both have consistently highlighted bioenergy and, and in particular BECCS, as a strategically valuable technology in meeting the UK’s 2050 targets cost-effectively and securely.
BECCS comprises two key elements – biomass energy and carbon capture and storage (CCS). Used together, they can uniquely, compared with other renewable technologies, deliver “negative emissions”. The need for negative emissions just got more important because our 2050 “net zero” target. But, it will be near impossible to remove all sources of anthropogenic GHG emissions – for example, from aviation and from agriculture. Some means of greenhouse gas removal from the atmosphere will be required to create an offset – we call these offsets “negative emissions”. A method to do this is to use BECCS. Plants (biomass) absorb carbon dioxide (CO2) from the atmosphere as they grow. Providing the rate of biomass removed (through harvesting, fires etc) does not exceed the rate of biomass growth and that the carbon stock in the plantation soil is maintained or increased through sustainable land management, then if that biomass when harvested is used as a fuel to generate power and the resultant carbon dioxide captured and permanently stored, for example in a depleted gas reservoir, then there will be a net removal of CO2 from the atmosphere – hence “negative emissions”. Examples of the types of biomass we can use in a BECCS system are specially grown energy crops such as Miscanthus which looks a little like bamboo (currently growing around the East Riding of Yorkshire and North Lincolnshire), and byproducts of the forestry industry.
“While afforestation and wood in construction are also available to us to store carbon and are vital established techniques, they require, as noted in this IPCC report, continual monitoring to maintain the level of carbon stored. Deployment of BECCS with the carbon dioxide stored underground provides permanent storage of carbon and provides additional capability to address climate change.”
Prof Duncan Cameron, Director of the Institute for Sustainable Food at the University of Sheffield, said:
“This IPCC report really highlights the scale and sheer complexity of the problems with our food system – there is no single solution. Too often, scientists argue over whether one approach is better than another – should we concentrate our food production on one single piece of land, accepting that we’ll do environmental damage, or should we spread the load so that no one ecosystem is completely destroyed? The reality is neither of those solutions is perfect, and the answer will depend on the dynamics of a particular place.
“So, at the Institute for Sustainable Food we’re pioneering an approach that recognises the need to slash greenhouse gas emissions from agriculture as a social and cultural problem, as much as it is a technical problem. We need solutions that are capable of working in the real world, and that doesn’t just mean technology – it means policy and working with governments. The status quo is not acceptable. We need tailored approaches for different communities and different landscapes.”
Prof Jonathan Leake, Professor of Animal and Plant Sciences at the University of Sheffield’s Institute for Sustainable Food, said:
“The IPCC Climate Change and Land report considers the potential contributions of methods like tree planting, agro-forestry and growing cover crops to increase organic carbon storage in biomass and soils. However, it appears to have overlooked arguably one of the most promising methods to simultaneously improve crop production, soil quality and sequester CO2 from the atmosphere – adding calcium silicate rock dusts (such as basalt) to agricultural soils, especially those that are moderately to strongly acidic.
“The report suggests 0.44Gt of CO2 per year could be sequestered if 25 per cent of croplands were to grow cover crops – while results published by the Leverhulme Centre For Climate Change Mitigation at the University of Sheffield last year in the Journal Nature Plants indicate that basaltic rock dust added to global croplands has the modelled potential to sequester CO2 at several times this rate into more stable forms of carbon. The effect is estimated to be of similar magnitude to reducing global deforestation and forest degradation.
“Adding rock dust to soils has also been shown in many studies to improve soil quality, boost crop yields, reduce pest and physical damage to crops, and reduce the need for fertilizer and agricultural lime – both of which are contributors to greenhouse gas emissions. The financial and practical barriers to implementing this approach are also likely to be lower than many of the options given prominence in the IPCC report. It’s crucial that scientists and policymakers consider this approach alongside the IPCC’s important recommendations.”
Dr. Amanda Thomson, Ecosystems Modeller, Centre for Ecology & Hydrology, said:
“This IPCC Special Report clearly sets out the risks to land and food systems from climate change and the potential for land-based management options to mitigate these risks and adapt to the consequences. The majority of these risks and management options have a high or medium degree of confidence, reflecting the substantial quantity of supporting science. The report highlights how reducing anthropogenic GHG emissions as quickly as possible will reduce the negative impacts of climate change on our land and food production systems. Delayed action will also mean we have a reduced range of mitigation options in the future, they will be more expensive, and we will need to apply them more widely.
“This report emphasizes that there are limits to how much we can apply measures, such as afforestation and bioenergy crops, to remove CO2 from the atmosphere. Applying these measures on a wide enough scale (several million km2 globally) would require a vast amount of land conversion, wouldn’t provide a permanent solution and could also increase food insecurity and land degradation. Instead, the report advocates sustainable land management (including forests) and reduced food loss/waste to avoid or reverse land degradation and promote food security and sustainable development.”
Dr Eugene Mohareb, Lecturer in Sustainable Urban Systems, University of Reading, said:
“Looking at the mitigation options section (B), the authors’ suggestions for reductions of food loss/waste are important as they provide a direct benefit in reducing greenhouse gases related to need for arable land (and associated inputs) and from their disposal in landfill. However, there are also knock-on carbon benefits throughout the food system by avoiding the need for carbon-intensive transport (both in distribution and collection from food retailers), food processing, retailing, packaging and refrigeration.
“Additionally, the emphasis on plant-based diets similarly has further benefits in the shifting from perishable animal products to pulses & legumes. These benefits include reduced cold storage requirements (throughout the supply chain, at food retailers, as well as in households) and reduced potential for food wastage due to their generally longer shelf life.”
Prof John Shepherd, Emeritus Professor in Earth System Science, University of Southampton, said:
“The report confirms that sensible use and management of land-based stocks of carbon, including crops and forests, can make a useful contribution to reducing climate change and its impacts. However, the magnitude of the effect is limited, and the report shows that planting trees is certainly not a magic bullet that can solve all our problems. The amounts of carbon stored in biomass and in soils can be increased substantially but not indefinitely, and these stocks of carbon then become vulnerable to both future mismanagement and climate change. Reducing food loss and waste, and modifying dietary choices can also make a substantial and useful contribution to reducing emissions, enhancing food security and improving the sustainability of our use of land. Better management of the use of land and the carbon it can store is highly desirable, but not enough on its own, and reducing emissions of carbon dioxide and other greenhouse gases is still the top priority.
“Bioenergy (using biomass for energy production) produces roughly the same amount of CO2 as burning coal (or even more) and can only be considered carbon neutral (maybe) if & when the biomass used has been regrown. In the short term it is just as bad as burning fossil fuels. With BECCS the CO2 produced is captured and stored somewhere, so in the short term it is (roughly) carbon-neutral since little or no CO2 is released, and it becomes carbon negative only in the long term if and when the biomass has been re-grown.
A good bioenergy crop is something that grows fast, does not need a lot of water or fertiliser, and is not much use for anything else (to reduce the payback period). Bioenergy/BECCS crops should only be grown on land that has already been de-forested and is marginal for other uses: not on agricultural soils and certainly not on land that is deforested for the purpose.”
Dr Anna Krzywoszynska, Associate Director at the University of Sheffield Institute for Sustainable Food, said:
“The IPCC warns that the current pattern of land exploitation and degradation built into our food systems is pushing the planet into climate breakdown. It stresses that in order to make the land use changes we urgently need, policymakers must engage with local populations and develop place-specific responses. I am delighted the IPCC report recognises the role that social learning, advisory services and public discourse must play in developing and spreading good land use practices.
“For policy and research institutions, this signals the need to work with farmers and local people in developing new technologies and practices for land regeneration – instead of imposing change from above. My work on the importance of supporting farmer-scientist communities around a shared objective of sustainable soil management supports the IPCC conclusions.”
Prof John Morton, Professor of Development Anthropology at the Natural Resources Institute, University of Greenwich, and Theme Leader for Climate Change in NRI’s new Food and Nutrition Security Initiative, said:
“Speaking as one of the authors, I’m proud that we’ve managed to address in one single integrated report climate change, food insecurity, and land degradation. These are separate but linked problems that hugely threaten humanity. The report helps our understanding of the linkages between the three problems and maps out some ways forward to increase food security while reducing greenhouse gas emissions. It also stresses the importance of good governance and inclusive, participatory decision-making in addressing these challenges”.
Prof Daniela Schmidt, Professor in Palaeobiology, University of Bristol, said:
“This assessment by the IPCC is a big step from pointing out the problem of climate change to suggesting adaption options and solutions. The report highlights how we can reduce climate change, for example, by reducing food waste which is 8-10% of green house gas emissions. Changing how we use the land importantly does not just reduce climate change but also land degradation, improves biodiversity and restores natural ecosystems.
“This report clearly points out that there is just limited land for food, feed and limited water while population is growing. At the moment, there is a lot of attention on nature based solutions such as bioenergy or growing trees. Some of these approaches need massive areas of land which is also needed to produce food. Large areas of trees can change the amount of heat reflected if they replace snow areas and will destroy the ecosystems they replace. Vast monocultures are highly vulnerable to diseases and pests and therefore not resilient. Using these though in brown land generates new habitats, creates green spaces for people and stores carbon.
“Fundamentally, these suggestions for change have multiple other benefits for people such as a better cities to live in, healthier environments, cleaner air, less waste and a more balanced diet. Some of these are local actions, individual choices and some need changes in policies. We need to learn from techniques working in different regions, adapt technologies, and consider financial support to make change happen.”
Prof William Collins, Professor of Meteorology, University of Reading, said:
“This report is very valuable in highlighting the effect land use has on climate. It assesses that human land use activities contributed significantly to greenhouse gas emissions over the last decade (13% of carbon dioxide emissions, 44% of methane emissions and 82% of nitrous oxide emissions). Thus it concludes that improvements in land use are essential to meeting 2 degree or even 1.5 degree climate targets. By showing how preserving and restoring forests and improving agricultural practices can benefit climate, biodiversity and communities, this report outlines potential ways to mitigate climate change based on comprehensive underpinning science.”
Prof Simon Lewis, Professor of Global Change Science, University College London, said:
“The report is an impressive synthesis of a really diverse scientific literature, confirming that we live on a human-dominated planet. Like other recent global reports, the new IPCC land report highlights that there are rising costs resulting from any delay in rapidly reducing greenhouse gases, with the poor paying the highest price [see D3 of report].
“What is clear from the report are the rising expectations of what land can provide. Land is needed to produce food for a population of 7.7 billion and rising, it is needed for biodiversity to stem the extinction crisis, and it is increasingly seen as playing a major future role in tackling climate change. Groups of interlocking policies will be needed to shift the management of land to achieve these multiple objectives. Chief among them will be reducing food waste and people eating more plant-based diets to reduce the land area needed for farming, which can free land for ecosystem restoration to remove carbon from the atmosphere and provide more space for nature [see C2 of report]. None of these land-related changes are a substitute for reducing emissions from fossil fuel use, as all sectors must reach net zero greenhouse gas emissions to stabilize the climate.
“The report shows that significant dangers lie ahead. The mass deployment of bioenergy crops either as a substitute for fossil fuels or for use in Bioenergy Carbon Capture and Storage, could either reduce the amount of land used to grow food for people resulting in hunger for the income-poor, or could replace natural lands, mostly forests, with severe biodiversity losses. [see Figure SPM 4].”
Prof Dave Reay, Professor of Carbon Management, University of Edinburgh, said:
“This is a perfect storm. Limited land, an expanding human population, and all wrapped in a suffocating blanket of climate emergency. Crop yields are already being hit hard by climate change, staples like wheat, maize and rice are all at risk. The global web that is our food system means that impacts on farms thousands of miles away ripple right back to our own dinner plates.
“We have many solutions, from improved crop varieties and livestock health, to smart farming technologies and soil management techniques. Together they can boost food production and resilience, secure livelihoods, and help protect the huge carbon stocks that are our forests, soils and peatlands. All these solutions are useless without sufficient access and support for the many millions of smallholder farmers around the world.
“Earth has never felt smaller, its natural ecosystems never under such direct threat. In 1919 the Scots town planner Patrick Geddes declared ‘By leaves we live’; a century later and his visionary message is still falling on deaf ears.”
Prof Piers Forster, Professor of Climate Change, University of Leeds, said:
“This important report shows that to limit temperature change below 1.5C, we need to substantially change the way we use our land. In a nutshell we need less pasture and more trees, but really it means thinking much harder about how we use every acre of land. Land needs to grow our food, provide biodiversity and fresh water, give work to billions of people, and suck up billions of tonnes of carbon. To make the necessary changes governments, land-owners, farmers and foresters need to get organised. We also need much better data collection to monitor how the land is changing and protect it from catastrophic risks.
“It’s a very timely report for the UK as we have an opportunity with Brexit to reform our farming policy to make it a sink of carbon rather than a source.”
Prof Stuart Haszeldine, Professor of Carbon Capture, University of Edinburgh, said:
“Land use choices confront the treble challenges of climate change uncertainty for crops; increasing soil degradation with industrial extraction of food from soil; and the toxic relationship between capital finance and emerging economy debt – which enables rich economies to buy their way out of trouble. How to choose fair fare: food or fuel; grain or meat; profit or persistence?
“This report goes to some of our most personal choices. In the privacy and freedom of our own homes, how far will well-meaning state intervention be able to penetrate? Or will the pester power of dietary demands from affluent educated children be more effective?”
Prof Peter Stott, Head of Climate Monitoring and Attribution, Met Office Hadley Centre, said:
“When you separate the land surface temperature records from those recording sea-surface temperature, it is clear that the earth’s land surface is heating up much more quickly than over the oceans. Already temperatures over many land areas have risen more than 1.5 °C above pre-industrial levels, the threshold referred to in the Paris agreement for global average temperatures. See graph.”
Dr Jason Lowe, Head of Knowledge Integration and Mitigation Advice, Met Office Hadley Centre, said:
“Future climate change is expected to cause large changes to land, making the risks to food security and a move towards desertification more severe.
“To limit global average temperature to below 1.5 °C almost certainly requires removing extra carbon-dioxide from the atmosphere. Many of the suggestions to do this have big implications for how we use the land for instance for food production.
“Wildfires, permafrost melt, and increasing desertification are putting a growing strain on land resources and these impacts are feeding more greenhouse gases back to the atmosphere, adding further to climate change, making it more difficult to limit warming to 1.5 °C.
“Even with very large reductions with greenhouse gas emissions, for example from generating energy it is increasingly clear that if we’re going to achieve net zero greenhouse emissions we’ll need to make better use of the land, such as growing more trees or increasing biofuel capacity along with carbon capture and storage.”
Dr Keith Kirby, Visiting Researcher, Department of Plant Sciences, University of Oxford, said:
“Increased tree planting in a British context does make sense as part of an adaptation/mitigation response but, as the report says, the local and regional context must be considered. For example, peatlands need to be conserved and not replaced with trees. Additionally, converting land from other uses into new forests can lead to conflicts with other interests, such as farming, conservation and maintaining the landscape.
“Forests can also contribute to carbon sequestration in the form of harvested wood products, but this depends on the life-span of the product. When wood is used as bioenergy this lifespan is short and so carbon sequestration is limited compared to, for example, use of timber in building construction.””
Prof John Quinton, Professor of Soil Science, Lancaster University, said:
“The IPPC report highlights the importance of maintaining the soil carbon stocks that we already have, by protecting soils from soil erosion, maintaining carbon stocks in wetlands and avoiding land use change from forests to agriculture. Emphasising the importance of avoiding land degradation to ensure food production for future generations and reduce harmful GHG emissions is an important message for policy makers.”
“Climate Change and Land, an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems” was published by the IPCC at 9am UK time Thursday 8 August.
Declared interests
Prof Colin Campbell: None to declare.
Dr Joeri Rogelj: Not involved in this report, but I led the global emission pathway assessment for the 2018 IPCC Special Report on Global Warming of 1.5°C
Prof Jane Rickson: I confirm I have no conflicts of interest when writing my comments.
Prof Mark Maslin: I have no conflicts of interest to declare and I was not an author or a reviewer of this report
Dr Jeff Price: No conflicts of interest
Prof Geriant Evans: I do not have any conflicts of interest.
Prof Duncan Cameron: No conflicts of interest
Prof Jonathan Leake: No conflicts of interest
Dr Amanda Thompson: I produce the land use and forestry components of the UK’s national greenhouse gas inventory (with a team at CEH and Forest Research) and advise the UK government on land use and forestry mitigation measures and GHG inventories.
Prof John Shepherd: No financial conflicts of interest.
Dr Eugene Mohareb: I declare no conflict of interest.
Prof John Morton: Prof Morton is a Lead Author of the report.
Prof Daniela Schmidt: I have no competing interests. I am the CLA for the IPCC chapter on Europe but have not contributed in any form to this report
Prof William Collins: I was an “Expert Reviewer” on this report.
Prof Simon Lewis: No conflicts of interest to declare.
Prof Dave Reay: “An expert reviewer for this IPCC special report. Author of ‘Climate-Smart Food. An expert advisor to the Scottish Government on Rural Policy. No other interests declared.”
Prof Piers Forster: “I have no conflicts of interest.”
Prof Stuart Haszeldine: Stuart Haszeldine researches on the energy transition, climate change, managing carbon and recapturing “negative” emissions. He holds funding from UK research councils NERC, EPSRC, and Scottish Gas Networks. He has no financial or management interests in commercial organisations.
Dr Keith Kirby: No declarations of interest.
