4.2.5 Tipping cascades

A positive tipping cascade occurs when one tipping point triggers at least one other in a domino effect or chain reaction (Sharpe and Lenton, 2020). This can happen wherever tipping points occur – either in subsystems, where they can help accelerate change in a larger system, or across coupled systems (Chan et al., 2020). Coupled systems may be between domains, sectors, institutions and/or countries. The resulting overall multi-system impact of the initial change is larger than the initial impact as a consequence of reinforcing feedbacks and other secondary effects within and across systems, which is also referred to as spiral scaling (Newell et al., 2021; Geels and Ayoub, 2023). As elaborated in Chapter 4.4, some systems that have the potential for tipping can also be thought of and utilised as cross-cutting enablers of tipping in other systems. For example, there may be tipping points in the uptake of new electricity storage systems, digital technologies, social norms, political coalitions, or systems of finance; these can also be used, individually or in combination, as strategic interventions to enable tipping points in other systems. When designed to trigger a positive tipping cascade, such interventions are referred to as super-leverage points (Meldrum et al., 2023). As examples, economies of scale in the production of renewable energies can lead to tipping points in the adoption of electric vehicles, and thereby foster innovations in industry and agriculture; mandating Zero-Emission Vehicles can accelerate this process and create positive synergies with other potential super-leverage points, such as mandating green ammonia for use in fertiliser production. Cheaper renewable power reduces the cost of running electrolysers and reduces costs of green ammonia in fertiliser production. This, in turn, can lead to economies of scale in green hydrogen supply chains and bring down the cost of green hydrogen for use in several other sectors. To use a non-technological example, a social movement like Fridays for Future could create positive tipping cascades across sectors and jurisdictions if, for example, a series of school strikes were to inspire a general strike of workers organised by the trade union movement and professional associations.

In subsequent chapters we illustrate the practical application of this framework with empirically evidenced case studies in the sectoral systems of energy, transport, food and land use (see Chapter 4.3). We also investigate cross-cutting enablers of PTPs in socio-behavioural, political and financial systems, digitalisation and early opportunity indicators (see Chapter 4.4). The chapter after that (see Chapter 4.5) is a more detailed investigation of positive tipping cascades in a range of human systems.