The impact of climate change on agriculture and land use was highlighted in the recent Sixth Assessment of the Intergovernmental Panel on Climate Change (IPCC) report on Impacts, Adaptation and Vulnerability.
Last year, as part of the same assessment, the IPCC’s climate science report showed how human influence has unequivocally warming the planet.
The new report focuses on assessing current observed climate change impacts and future vulnerability, adaptation options and their effectiveness, feasibility and limits, as well identifying actions and strategies that could contribute to climate resilient development.
Causes for concern
In the Europe chapter of the new report, where I was a lead author, two key risks directly related to agriculture were identified.
The first risk is substantive losses in agricultural production for most European areas over the 21st century. This would be exacerbated by, and contribute to, the threat of water scarcity, a second of the key risks. In both cases increases in global warming raise the level of risks, as well as limiting the effectiveness of adaptation strategies to them.
There are many ways that agricultural practises, and land use more generally, can be adapted in the face of a changing climate. Farm management adaptations could include changing sowing and harvest dates and irrigation practises, as well as using more resilient crop strains or switching to different crop or land use.
Irrigation is an effective way to adapt to both higher temperatures and lower rainfall, but the increasing scarcity of water in areas where irrigation is most needed makes this problematic. We are already depleting groundwater resources in many locations and such sources are clearly not sustainable solutions, this severely limits the extent of the role which irrigation can play.
Other options can also be effective, but the harms from climate change are increasingly difficult to avoid as levels of warming rise. At a global warming level of 3°C or greater above pre-industrial levels, even a combination of all adaption measures would not be enough to limit significant damage to European agricultural production.
The poorest hit hardest
There are places where crop yields will increase with some warming, including in some more northerly parts of Europe. However, these gains are more than offset by reductions in yields in hotter and dryer regions. For example, yields of maize in Southern Europe could drop by more than 50 per cent in higher warming climate scenarios.
The globalised nature of today’s food system means that people are affected by changes in food production no matter where it occurs. Even people in regions where the direct impacts on agriculture are not as severe would experience higher food prices due to climate impact on global food production.
Globally, as well as within regions and countries, the individuals who are most vulnerable to climate change are the least well off, as they have a lower capacity to adapt to, and recover from, direct impacts on them. Also, increases in food prices will disproportionately affect them as more of their incomes are spent on subsistence. It all adds up to exacerbating existing inequalities.
Land is a finite resource
In addition to land being under pressure from the need to adapt to changes in climate, greater carbon sequestration, for example through tree planting, can help mitigate those changes.
Land is also needed to halt biodiversity loss and support other ecosystem functions. Such competing claims on land are often in direct conflict, with multiple interactions and unintended consequences. The connections between land-based climate adaptation and mitigation and conservation is an area where greater understanding is critically needed.
Limit and adapt
In Europe and around the world, the level for risks for the food system functioning ecosystems and human health are substantially increased by higher levels of warming.
As temperatures rise, the effects and vulnerabilities become more severe. Adaptation options become more limited and less effective. However, if we limit warming close to 1.5°C above pre-industrial levels there are potential adaptation options that are effective.
As the report underscores, we need to limit warming to as close to this target as possible, and to avoid pathways that do not limit warming to less than 2°C.
The views expressed in this section are those of the contributors, and do not necessarily represent those of the University.
Picture credits: hands holding grain – RoyalRegina/Getty; tractor in crops – Daniel Balakov/Getty; italian orchards – Stefan Rotter/Getty