The development of scenarios to examine the role of technology change and consumers in delivering cumulative emission reductions and adapting to climate impacts under a 2o & 4oC future

The rate of emission reductions required to deliver a global temperature stabilisation target of 2oC and even o4C are substantial. For stabilisation at 2oC, published global emission reduction rates range from 3% per annum globally to over 9% per annum for developed countries. Delivering these targets will be challenging, technically, socially, economically and politically. However, if mitigation policies fail to deliver a 2oC stabilisation, a different challenge is faced, that of adapting to the impacts of 4oC plus. These inter-related challenges are exemplified in the food system which is both a major source of emissions and is susceptible to future climate impacts. This paper presents a scenario methodology developed to produce coherent storylines of how technological change to reduce the climate impact of the supply chain coupled with changes in consumption practices, with particular reference to food, could deliver consumption based emission reduction pathways commensurate with 2o & 4 oC in the UK. Qualitative scenario storylines are developed using a backcasting framework with a series of workshops and interviews with key stakeholders and consumer focus groups. These are quantified where possible using a multi-region environmentally extended input-output model to capture consumption based emissions. A number of iterations are used to ensure the technology and consumer changes are commensurate with the chosen cumulative emissions pathway under 2 and 4oC futures. The scenarios highlight the differing roles of technological change and the consumer in delivering emission reductions and the differing climate impacts and thus adaptation requirements associated with 2 and 4oC. The results can be used to assess the gap between the emission reductions delivered through existing territorial based emission reduction strategies and those required if taking a ‘consumer’ based view and to assess the trade-offs between higher mitigation rates and differing adaptation challenges.