The Intergovernmental Panel on Climate Change (IPCC) report last week puts a spotlight on the unique part of the world that is crucial to combatting the climate crisis — the land. In a nutshell, the report tells us we need a complete transformation of our land and food systems, whilst drastically cutting fossil fuel emissions if we are to keep global warming to the Paris Agreement’s 1.5°C limit.
So what does the new Special Report on Climate Change and Land tell us?
How much land?!
Humans use a lot of land — more than any time in history. Our footprint directly affects more than 70% of the ice-free land surface — and all of it is impacted one way or another by climate change, for example through rising surface temperatures and more intense extreme events.
A source and sink
The way we use land drives climate change and climate change affects land — it cuts both ways. Human activities in agriculture, forestry and other land use are a big source of human-induced greenhouse gas emissions — around 23% of the global total — so are a big driver of climate change. Reducing emissions from land can be a big part of the solution.
Natural land processes can also act as a sink. Photosynthesis draws down carbon dioxide (CO2) from the atmosphere and fixes it in plants and then into soils. The Keeling curve shows this process with the rising trend of atmospheric CO2 overlaid by an annual dip during the Northern Hemisphere spring when leaves grow rapidly and remove huge amounts of carbon from the air. Overall the land is a net sink which removes around 29% of total human-induced CO2 emissions. Increasing the land sink by restoring ecosystems or planting trees is another big part of the solution.
Food for thought
The report highlights the urgent need to transform our food system, to both limit climate change and secure food supplies. The global food system contributes around 30% of human-induced greenhouse gas emissions. This includes the clearing of natural ecosystems for agriculture (more than half of which happens in grasslands and savannahs and much of the rest is deforestation); on the farm (e.g. from ruminants and the overuse of fertiliser); and the transport and refrigeration needed to get food to our plates.
Wasted food has a shockingly high impact: we don’t consume 25–30% of total food produced which results in 8–10% of total human-induced greenhouse gas emissions. Globally we currently produce enough food for the estimated global population of 10 billion in 2050 but inefficiencies in our consumption and distribution systems drive a constant pressure to produce more than we need.
The report is clear that not wasting food along with dietary choices (a healthy, plant-based diet) can both help reduce pressure on land and greenhouse gas emissions.
The triple challenge
What we do with land is complex and the report highlights a triple challenge of limiting climate change, restoring nature and ensuring food security (an important part of sustainable development). The land area is finite and it can be used for different purposes so competition can arise — however, the IPCC shows that there can be synergies…
Sustainable land management
There are win-win-wins — those actions which are good for climate change adaptation and mitigation which can also protect nature and improve food security. But it needs doing carefully.
What can we do now?
There are a number of priorities. First, we need to halt conversion of natural habitats to protect existing carbon stores, biodiversity and vital ecosystem services. Natural habitat conversion releases large amounts of CO2 and drives massive biodiversity loss. Second, we need to restore natural habitats such as wetlands and savannahs as this increases their carbon sequestration and improves resilience to future climate change. Third, we need to modify the way we produce agricultural products — for example by using land that we have already converted more sustainably and efficiently to feed a growing population, and reducing emissions and increasing below-ground carbon stocks at scale. Fourth, we need a fundamental shift to a better way of using and consuming food. As discussed above, we can reduce pressure on land and reduce greenhouse gas emissions by cutting food loss and waste and shifting to healthier, sustainable diets.
Land as part of raising climate ambition
Around a quarter of current climate pledges under the Paris Agreement come from land-sector related actions such as reduced emissions from deforestation and forest degradation or agriculture. Raising ambition around land-based mitigation (considering all the synergies and trade-offs) will be an important part of tackling climate change. The report is clear that action on land sector alone is not enough alone and it in no way gives coal, oil and gas a free-pass.
So how does this fit into the international landscape?
It is clear that business as usual is no longer an option. Transformative, immediate, systemic and scaled up climate action is needed if we are to have any chance of keeping warming to 1.5℃.
This IPCC report is the most comprehensive assessment of the science around climate change and land to date. Governments must now raise their climate ambition based on the science.
Next month, nature-based climate solutions will be one theme of the UN Secretary General’s New York Climate Summit. Then, in December, Chile hosts the UNFCCC COP. These are two opportunities this year for governments to publically commit to increasing the ambition of their national climate pledges. Enhanced action in the land-sector and other nature-based climate solutions — alongside tough targets in other sectors like energy and transport — is how we can ensure a sustainable world.
Dr Stephen Cornelius is the Chief Adviser on Climate Change and IPCC lead for WWF. He led the WWF team at the IPCC Special Report on Climate Change and Land approval session in Geneva. Follow him on twitter @SteveJCornelius.
WWF is an observer organisation to the IPCC
