The IPCC Special Report on Land: We have to act now

On August 8^th 2019, the IPCC (International Panel on Climate Change) released its special report on climate change and land. This report fills a large gap, being the first comprehensive analysis of the pressure of climate change on land and the potential of terrestrial systems to also assist in alleviating climate change.

It builds on last year’s dire warning of the consequences of exceeding 1.5C of warming. The key message is twofold:

• We need to dramatically change the way we produce food and manage land. Transforming to clean energy, clean transport and industry alone will not cut global GHG emissions enough to avoid dangerous warming above 1.5C.
• We have to act urgently in all sectors to avoid irreversible loss in land ecosystem functions and services required for food, health, habitable settlements and production.  Actions in the land sector cannot substitute for strong action in other sectors.

The long-winded title gives a snapshot of the complexity of issues involved:

IPCC SPECIAL REPORT ON 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.

This is in the context that human activities already impact 70+% of the of the global, ice-free land surface. Since the pre-industrial period, the land surface air temperature has risen nearly twice as much as the global temperature has risen overall. That is, it is already even hotter over land than mean global temperature rise statistics imply.

Actions in the land sector such as transition towards agroecology and greater protection and restoration of forests, peatlands and wetlands are crucial. So too, are actions taken elsewhere that reduce direct impacts on land, in particular dietary change and reduction of food waste. Land tenure security for the poor and marginalised, with a focus on indigenous peoples and local communities, has a key role to play in delivering results, not to mention equity.

Large Scale Bioenergy and BECCs untenable

Large scale bioenergy and BECCS (Bioenergy with Carbon Capture and Storage) is not a ‘get out of jail free’ card.  A stark picture is painted of the enormously damaging impacts on food security, ecosystem and land degradation and desertification, and adaptation – a tidal wave of impacts on people and nature that effectively rule out the mass tree plantings required by these controversial mitigation schemes that could cover the entire global extent of current cropland.

Studies linking bioenergy and BECCS to food security estimate an increase in the population at risk of hunger to up to 150 million people at this level of implementation, with up to 15 million square km of additional land required in 2100. Impacts on desertification and land degradation are also at the highest end of the scale. [Figure SPM.3 Potential global contribution of response options to mitigation, adaptation, combating desertification and land degradation, and enhancing food security.]

Viable emissions reduction pathways without big bioenergy and BECCS

The IPCC clearly states that there are viable pathways for limiting global warming to 1.5°C that reduce the dependence on bioenergy and BECCS drastically, and highlights that the modelled pathways assessed only include a fraction of the possible response options. More comprehensive mitigation could further reduce the need for bioenergy and CDR. This is a significant step forward in the discussion on possible future trajectories and alleged necessity to geoengineer the planet to reach 1.5°C. We have choices:

B 7. Future land use depends, in part, on the desired climate outcome and the portfolio of response options deployed (high confidence). All assessed modelled pathways that limit warming to 1.5ºC or well below 2°C require land-based mitigation and land-use change, with most including different combinations of reforestation, afforestation, reduced deforestation, and bioenergy (high confidence). A small number of modelled pathways achieve 1.5ºC with reduced land conversion (high confidence) and, thus, reduced consequences for desertification, land degradation, and food security (medium confidence). {2.6, 6.4, 7.4, 7.6; Cross-Chapter Box 9 in Chapter 6; Figure SPM.4}

Irreversible impacts without urgent emissions reductions across the board

Returning to core, overarching messages from the IPCC, we cannot delay and we cannot rely on actions taken in the land sector to substitute for actions that must be taken urgently in other sectors to reduce emissions. We do need to take action on land, however. The last paragraph of the report is the kicker:

D3.3. Deferral of GHG emissions reductions from all sectors implies trade-offs including irreversible loss in land ecosystem functions and services required for food, health, habitable settlements and production, leading to increasingly significant economic impacts on many countries in many regions of the world (high confidence). Delaying action as is assumed in high emissions scenarios could result in some irreversible impacts on some ecosystems, which in the longer-term has the potential to lead to substantial additional GHG emissions from ecosystems that would accelerate global warming (medium confidence). {1.3.1, 2.5.3, 2.7, 3.6.2, 4.9, 4.10.1, 5.4.2.4, 6.3, 6.4, 7.2, 7.3; Cross-Chapter Box 9 in Chapter 6, Cross-Chapter Box 10 in Chapter 7}

This is strong confirmation of the ‘tipping point’, the negative spiral of compounding feedback loops we risk every day we continue as societies and individuals with business-as-usual instead of strong climate action.

Special role of land

The special characteristics of land in relation to greenhouse gases are that it is both a source of emissions and a sink for GHGs as growing vegetation draws down carbon from the atmosphere and stores it in forests and other carbon rich ecosystems, soils and planted crops.

Yet land is so much more than this:

 A 1. Land provides the principal basis for human livelihoods and wellbeing including the supply of food, freshwater and multiple other ecosystem services, as well as biodiversity. Human use directly affects more than 70% (likely 69-76%) of the global, ice-free land surface (high confidence). Land also plays an important role in the climate system. {1.1, 1.2, 2.3, 2.4, Figure SPM.1}

A1.1. People currently use one quarter to one third of land’s potential net primary production for food, feed, fibre, timber and energy. Land provides the basis for many other ecosystem functions and services, including cultural and regulating services, that are essential for humanity (high confidence). In one economic approach, the world's terrestrial ecosystem services have been valued on an annual basis to be approximately equivalent to the annual global Gross Domestic Product (medium confidence). {1.1, 1.2, 3.2, 4.1, 5.1, 5.5, Figure SPM.1}

The time has arrived for nature based solutions

Nature based solutions are key to the changes required to keep our planet safe for people and the panoply of life with which we share the Earth. The massive climate and biodiversity crises imply we must leave space for nature, for ecological restoration, to grow healthy food, and for livelihoods for the most vulnerable.

The report embraces such natural solutions across the landscape, with these featuring in the various parts addressing different land uses such as food production, mitigation through sequestration and emissions reduction, and adaptation and resilience.

Changed land management approaches have multiple positive effects

The impetus to change land management to tackle climate change is found to contribute positively on many fronts including sustainable development, alleviation of poverty, reduced competition for land, more space for nature, and better food security.

B 2. Most of the response options assessed contribute positively to sustainable development and other societal goals (high confidence). Many response options can be applied without competing for land and have the potential to provide multiple co-benefits (high confidence). A further set of response options has the potential to reduce demand for land, thereby enhancing the potential for other response options to deliver across each of climate change adaptation and mitigation, combating desertification and land degradation, and enhancing food security (high confidence). {4.8, 6.2, 6.3.6, 6.4.3; Figure SPM.3}

B2.2. A wide range of adaptation and mitigation responses, e.g. preserving and restoring natural ecosystems such as peatland, coastal lands and forests, biodiversity conservation, reducing competition for land, fire management, soil management, and most risk management options (e.g. use of local seeds, disaster risk management, risk sharing instruments) have the potential to make positive contributions to sustainable development, enhancement of ecosystem functions and services and other societal goals (medium confidence). Ecosystem-based adaptation can, in some contexts, promote nature conservation while alleviating poverty and even provide cobenefits by removing greenhouse gases and protecting livelihoods (e.g. mangroves) (medium confidence). {6.4.3, 7.4.6.2}

Natural solutions in ecosystems

It is not a luxury to care for nature but an imperative to get conservation and restoration up as a serious priority for action. These are essential actions for mitigation and adaptation, and to tackle the climate and biodiversity emergencies together. The IPBES Global Assessment Report on Biodiversity and Ecosystem Services report is cited at the outset as the IPCC authors strive for ‘coherence and complementarity with other recent reports’.

Protecting forests and other carbon rich ecosystems as stable resilient carbon stores feature as vital immediate response options, whilst restoring degraded natural ecosystems is equally important but takes more time to achieve.

B1.2. While some response options have immediate impact, others take decades to deliver measurable results. Examples of response options with immediate impacts include the conservation of high-carbon ecosystems such as peatlands, wetlands, rangelands, mangroves and forests. Examples that provide multiple ecosystem services and functions, but take more time to deliver, include afforestation and reforestation as well as the restoration of high-carbon ecosystems, agroforestry, and the reclamation of degraded soils (high confidence). {6.4.5; Cross-Chapter Box 10 in Chapter 7}

The report is strong on reducing deforestation and forest degradation:

B5.3. Reducing deforestation and forest degradation lowers GHG emissions (high confidence), with an estimated technical mitigation potential of 0.4–5.8 GtCO2 yr-1…

Natural solutions in food production

On food production, the science found that the way we produce food and manage land must change dramatically if we are to avert catastrophic climate change. Farming must work with nature, not against it. The report rings the changes for industrial agriculture. Agroforestry and other ecological solutions already being pursued in both traditional and regenerative agricultural systems around the world, have an important role to play. Empowering women farmers and improving resilience to impacts of climate change are now essential.

Reducing food waste and changing diets

Actions to reduce the pressure on land for agricultural production are also vital. This is not only about being more efficient on the ground, but about elevating food waste as a key priority to be urgently addressed, given that up to a third of food produced is wasted and that food loss and waste contributes 8-10% of GHG emissions.

The personal becomes planetary as dietary shift moves into the spotlight. Whilst shirking naming meat explicitly, the report is clear that it is not only individual health but planetary health that now relies on adoption of predominantly plant-based diets.

B6.2. Diversification in the food system (e.g., implementation of integrated production systems, broad-based genetic resources, and diets) can reduce risks from climate change (medium confidence). Balanced diets, featuring plant-based foods, such as those based on coarse grains, legumes, fruits and vegetables, nuts and seeds, and animal-sourced food produced in resilient, sustainable and low-GHG emission systems, present major opportunities for adaptation and mitigation while generating significant cobenefits in terms of human health (high confidence). By 2050, dietary changes could free several Mkm2 (medium confidence) of land and provide a technical mitigation potential of 0.7 to 8.0 GtCO2e yr-1, relative to business as usual projections (high confidence). Transitions towards low-GHG emission diets may be influenced by local production practices, technical and financial barriers and associated livelihoods and cultural habits (high confidence). {5.3, 5.5.2, 5.5, 5.6}

The political messages

The political messages coming out of the IPCC at this point are very similar to those expressed in the IPCC’s Special Report on 1.5C: It is possible to limit global warming to 1.5 and vital to do so to avoid irreversible impacts on land systems that would then exacerbate the climate crisis.

However, limiting global warming to 1.5°C requires fast and spirited climate action and deep emissions cuts that can be only be achieved though actions in all sectors. Land can play a role but it, and all dependent on it, are also at risk. Action here is imperative but no substitute for strong action on fossil fuel use and the comprehensive upscaling of renewable energy.  Changes in production and consumption patterns are vital as well as the protection and wide-ranging careful restoration of our natural ecosystems.