Humankind is using land in an unsustainable way that, when combined with climate change, puts the world at risk of food instability, increasing food prices, worsening flooding, widening deserts and growing water scarcity, according to a landmark United Nations' report.
People currently use one-quarter to one-third of land's potential net primary production for food, feed, fiber, timber and energy, said the Aug. 8 report by the U.N.'s Intergovernmental Panel on Climate Change, or IPCC. But climate change is making it more difficult to use the land for those purposes and is "exacerbating existing risks to livelihoods, biodiversity, human and ecosystem health, infrastructure, and food systems," the report said.
Among other things, the price of grains such as wheat and corn could increase globally up to 23%, with a median increase of 7.6%, by 2050 due to climate change, the IPCC found. "The most vulnerable people will be more severely affected."
But all hope is not lost, the IPCC added. In addition to the reduction of emissions that will be needed to achieve the goals of the Paris Agreement on climate change, a global shift away from a meat-heavy diet, a reduction in food loss and waste, and more sustainable farming and forest management practices could greatly reduce some land-related risks.
A farmer seeds a crop in a field.
Increasing attention has been paid in recent years to land-based climate change risks, particularly for companies that rely on agriculture in their supply chains. Institutional investors representing more than $16 trillion in assets under management are part of the Farm Animal Investment Risk & Return initiative that was launched in 2015. That group aims to help investors understand environmental, social and governance risks and opportunities related to factory farming. Also, supermarket company Carrefour SA launched a sustainable farming initiative in January.
Ramifications for renewable generation performance
But companies dependent on agricultural products are not the only ones at risk, the report indicated. Mismanagement of land can cause broader problems with water supplies and increase land erosion — two issues that could cause headaches for industries with underground infrastructure or that are dependent on water to operate their equipment.
Moreover, the ability to reduce emissions through increased renewable generation could be hampered in some places due to poor land management. Desertification of land and resulting increases in dust storms can hurt the performance of wind and solar projects "through dust deposition, reduced reach of solar radiation and increasing blade surface roughness," the IPCC found. Dust storms also can reduce effective electricity distribution in high-voltage transmission lines, the report said.
Agriculture, forestry and other types of land use account for 23% of human-caused greenhouse gas emissions. At the same time, natural land processes potentially can absorb almost one-third of carbon dioxide emissions from fossil fuels and industry, the report found. The report also noted that 25% to 30% of total food production is lost or wasted annually.
Two-years in the making, the IPCC report connects the dots between the findings of more than 7,000 scientific studies. The final report was prepared by more than 100 leading scientists from 52 countries, most of whom are from developing areas. The IPCC in October 2018 released a report that warned the world needs to act more quickly to reduce greenhouse gas emissions to avoid more dire effects of climate change.
The new report builds on the IPCC's 2018 report and finds that limiting global warming to 1.5 degrees C or well below 2 degrees relative to preindustrial levels will "require land-based mitigation and land-use change." But the ability to use land-based solutions to absorb carbon from the air will decline as temperatures rise, the IPCC warned.
The use of biomass power production in combination with carbon capture and sequestration technologies also could help reduce global emissions, the IPCC found. That said, care should be taken to ensure that the large-scale expansion of bioenergy does not result in increased competition for land, loss of biodiversity or nutrient leakage, the report said.
Putting numbers on the risks
The IPCC throughout the report showed that land-based problems will only grow worse as global temperatures rise. One exception, however, is in higher-elevation areas, which could see better crop yields due to increased carbon dioxide levels.
But in drylands, climate change and desertification are projected to cause reductions in crop and livestock productivity as well as in biodiversity. Asia and Africa are expected to have the highest number of people vulnerable to increased desertification, while North America, South America, the Mediterranean, southern Africa and central Asia may be increasingly affected by wildfire. The tropics and subtropics are projected to be most vulnerable to crop yield decline.
By taking steps now, however, some of those risks can be reduced, the report said.
The IPCC estimated that improved crop and livestock activities and agroforestry have the potential to lower emissions by as much as 9.6 gigatonnes of carbon dioxide equivalent by 2050 and that reducing meat intake in diets could cut up to another 8 gigatonnes of CO2 equivalent emissions. Dietary changes and the reduction of food loss and waste each could free up several million square kilometers of land, the report said.