Climate change is negatively affecting agriculture and livestock production, but there was little scientific knowledge about which regions of the Earth would be affected or what might be the greatest risks. A new study estimates how much global food production will suffer if greenhouse gas emissions are not reduced.
According to the study, the scenario of losing a third of food will definitely happen if carbon dioxide emissions continue to grow at their current rate. In the study, the scientists defined the concept of a safe climatic space – areas where 95% of crop production is currently produced, thanks to a combination of three climatic factors: precipitation, temperature and aridity.
“Our research shows that a rapid, uncontrolled rise in greenhouse gas emissions could by the end of the century put more than a third of the world’s current food production in a no-food environment. The good news is that only a fraction of food production will face unprecedented conditions if we collectively cut emissions and limit warming to 1.5–2°C. ”
Matti Kummu is Professor of Global Water and Nutrition at Aalto University.
Changes in rainfall and aridity, as well as climate warming, especially threaten food production in South and Southeast Asia and the Sahel region of Africa. These are areas that lack the ability to adapt to changing conditions.
Food production has evolved in a fairly stable climate during the slow warming period following the last ice age. Continuous growth in greenhouse gas emissions could create new conditions, and food and livestock production simply will not have enough time to adapt.
The study used two future climate change scenarios: one in which carbon dioxide emissions are drastically reduced, limiting global warming to 1.5–2°C, and another in which emissions continue to rise steadily.
The researchers estimated how climate change will affect 27 of the most important food crops and seven different types of livestock, given the varying ability of societies to adapt to change. The results show that threats affect countries and continents in different ways. In 52 of the 177 countries studied, all food production in the future will remain in a safe climate space. These include Finland and most other European countries.
Already vulnerable countries such as Benin, Cambodia, Ghana, Guinea-Bissau, Guyana and Suriname will be hard hit if changes are not made; up to 95% of current food production falls outside the safe climate space. These countries also have significantly less capacity to adapt to the changes caused by climate change than wealthy Western countries. Overall, 20% of global crop production and 18% of livestock production are at risk, in countries with low resilience to adapt to change.
Researchers estimate that if carbon dioxide emissions are brought under control, the largest climate zone in the world today – the boreal forest, which stretches across northern North America, Russia and Europe – will shrink from the current 18.0 to 14.8 million km² by 2100. If emissions are not reduced, only about 8 million km² of vast forest remains. In North America, the changes will be even more dramatic: in 2000, the area covered about 6.7 million km², and by 2090 it may be reduced to one third.
The Arctic tundra is going to get even worse: it is estimated that it will completely disappear if climate change is not curbed. At the same time, it is estimated that areas of tropical dry forests and tropical deserts will grow. By the end of this century, we will see over 4 million km² of new desert around the world.
While this study provides the first comprehensive look at the climatic conditions in which food is grown today and how climate change will affect these areas in the coming decades, its underlying message is by no means unique: the world needs urgent action.