A paper published in One Earth in May 2021asserts that under the worst-case climate change scenario, regions equivalent to one-third of the world's food production could fall outside the safe climatic space suitable for agriculture.

The paper states that ecosystems and human societies have adapted to a relatively stable Holocene (the current geological epoch) climate for the past several thousand years and modern food production systems have developed under these conditions. However, in recent years, global environmental changes and climate change have accelerated, and changes in temperature, rainfall and aridity are affecting food production.

The paper refers to the safe operating space (SOS) in planetary boundary, which corresponds to the area where the earth can maintain its basic functions by exercising its own resilience and humans can operate safely. While many studies have analyzed changes in agricultural conditions under climate change, especially the impact on yields, the authors emphasized the need to define a safe operating zone (SOS) for agriculture as well as a climate niche concept for humans. In this context, the Holdridge life zone (HLZ) concept was used to simultaneously measure changes in multiple climatic characteristics, and to classify the earth into 38 zones based on annual precipitation, biotemperature and aridity, which play important roles in both crop and livestock production. The paper also introduced the concept of safe climatic space (SCS), which incorporates the climatic conditions in which food production can adapt to, as a concept that follows SOS and climate niche by integrating the three indices along the HLZ concept. The authors then conducted an analysis that considered the possible changes to the HLZ over the next 80 years due to climate change, 27 major food crops and 7 major livestocks production, and the resilience of humanity to cope with change.

The results suggest that under a scenario of rapid increase in greenhouse gas emissions, there will be a shift in the HLZ, with a decrease in tundra and boreal forest areas and an increase in boreal desert, temperate desert and temperate forest areas. It was also estimated that one-third of the world's food production, equivalent to 31% of crop and 34% of livestock production, will be out of the SCS by 2081-2100. The most vulnerable areas are projected to be in South and Southeast Asia and the Sudan-Sahel zone in Africa, with inherently low resilience to climate change. These results imply the importance of committing to scenarios that curb greenhouse gas emissions.

In the JIRCAS Environment Program, we are pursuing research projects on the development of comprehensive agricultural technologies for climate change mitigation and adaption in Monsoon Asia (Climate Change Measures in Monsoon Asia), and the development of sustainable land management technologies under extreme weather conditions in drylands of Africa and South Asia (Sustainable Land Management in Drylands). In the Food Program, we have research projects on development of sustainable rice cultivation and food production system in Africa (Africa Rice Farming System), and technology development towards supporting farmers' decision-making to boost sustainable upland farming system in Africa (Africa Upland Farming System). By developing technologies in collaboration with research institutions in developing countries, JIRCAS aims to contribute to climate change countermeasures and food security through science and technology.

Reference
Matti Kummu et al, Climate change risks pushing one-third of global food production outside the safe climatic space, One Earth (2021). https://www.sciencedirect.com/science/article/pii/S2590332221002360

Contributor: IIYAMA Miyuki (Director, Information Program)