4.5.2.2 Cascading effects in social-ecological systems

Food and land use is one of the key systems (4.3.3) that can create tipping dynamics for accelerated decarbonisation. Self-reinforcing feedback loops such as increasing returns and technological reinforcement can progressively push an inadequate into a more sustainable food system (Lenton et al., 2022; Fesenfeld et al., 2022). 

The role of society is considered a key driver of transformation in the food system, as widespread behaviour changes towards lower waste, sustainable diets and diversified protein sources can not only reduce the GHG emissions of the agriculture sector but also create synergies for achieving multiple SDGs, such as alleviating hunger, improving public health and averting biodiversity loss, and reducing the intensity of the tradeoffs between them (van Vuuren et al., 2018; Leclere et al., 2020; Obersteiner et al., 2016).

As dietary behaviour changes reduce land pressure, fertiliser consumption is expected to decline, and adoption of diversified and regenerative farming practices are expected to increase (Gosnell et al., 2019), as well as ecological restoration and associated carbon sequestration, leading to more rapid decarbonisation in agriculture (4.3.3.5). In climate vulnerable, low-income economies, these feedbacks can also drive diversification of livelihoods, new economic opportunities, and other social benefits (4.3.3.4). Social norms have been repeatedly shown to be a key driver of widespread dietary changes in model-based studies (Eliot, 2022; Eker et al., 2019). Public procurement of sustainable food is considered a strategic intervention to accelerate the adoption of new norms (UNGSDR, 2023), and food labelling and certification in alternative food networks (Lenton et al., 2022) is key for facilitating market penetration of alternative proteins. Therefore, such triggers in society and policy can have cascading impacts on intensified and accelerated transformation of food and land use systems.