Around a third of the world’s agricultural land could no longer be suitable for agricultural production in 2090. This is the result of a study by Finnish and Swiss scientists in the event that no further measures are taken against global warming. According to the computer models, countries south of the Sahara, South America and South and Southeast Asia would be worst affected. In Germany, the agricultural land would still be in the safe climatic area, but subtropical forests could grow in some regions.
The Study by a group led by Matti Kummu from Aalto University in Espoo (Finland) is in the journal “One Earth” published. “The good news is that only a fraction of food production would be exposed to unprecedented conditions if we worked together to reduce emissions so that warming would remain limited to 1.5 to 2 degrees,” explains Kummu. In this case, only around eight percent of the arable land and five percent of the pasture land would be outside of suitable climatic conditions in 2090.
Usable areas no longer offer the necessary conditions
Kummu and colleagues took the period 1970 to 2000 as the basis for the climatic conditions under which 95 percent of arable farming and cattle breeding were carried out. They defined these conditions as a “safe climatic space”. Then they compared these conditions with the changes that will result from climate change according to models from the status reports of the Intergovernmental Panel on Climate Change (IPCC). The most favorable scenario is the socio-economic development path SSP1 in connection with the representative concentration path RCP2.6. The development according to the SSP5-8.5 scenario would be worst if no measures were taken against climate change.
In the worst case, 31 percent of the arable land and 34 percent of the pasture areas would no longer be available due to the climate. Another third of the areas would be at great risk of falling out of the safe climatic space. Some countries would be hit particularly hard: Guyana and Suriname in South America, Ghana and Guinea-Bissau in Africa and Cambodia in Asia. In these states, 95 percent of the agricultural area would no longer be in the zone of suitable climatic conditions. In many of their neighboring countries, 80 to 85 percent of today’s usable space could no longer offer the necessary conditions.
More than four million square kilometers of new desert
According to the calculations, vegetation would also change significantly with continued climate change: Boreal forests and tundras would decrease significantly, dry forests would increase significantly in the tropics and deserts would grow in all climatic zones. “If we let emissions go up, the increase in desert areas is particularly worrying, since under these conditions hardly anything can grow without irrigation,” says Kummu. By the end of this century, more than four million square kilometers of new desert could emerge worldwide.
Other factors such as population growth, soil degradation and an increased risk of extreme weather conditions could exacerbate the effects of the climate crisis. “We have to mitigate climate change and at the same time increase the resilience of our food systems and societies,” emphasizes co-author Matias Heino, also from Aalto University.