Impacts and trade-offs of future land use and land cover change in Scotland: spatial simulation modelling of shared socioeconomic pathways (SSPs) at regional scales

Current estimates suggest that the world is on track for ~3°C of heating relative to pre-industrial levels by 2100. This is likely to bring great disruption to earth systems, leading to increased natural hazard risks, crop failures, civil unrest and population migration. There is, however, a high degree of uncertainty about the impacts that such events may have on land use and ecosystems in individual countries. Integrated assessment modelling (IAM) of scenarios like the Shared Socioeconomic Pathways (SSPs) offers one way to address this uncertainty, allowing outcomes such as the relative land cover under food production or forestry to be compared for each scenario. However, global and continental-scale IAMs need to be complemented by landscape scale spatial modelling to inform national and regional policy making. In this paper, we demonstrate impacts and trade-offs of future land cover change in Scotland, a UK region with a high degree of political autonomy, using downscaled SSPs from Europe to the national and finally the regional level. Our methods integrate participatory knowledge co-construction approaches with land-use modelling. Firstly, a stakeholder workshop held in November 2018 led to the development of detailed narratives for 5 UK SSPs. Two contrasting UK SSPs, SSP1 (Sustainability), and SSP5 (Fossil-Fuelled Development) were then adapted to the case of Scotland and simulated to the year 2040 using a land use change model (APoLUS). Land use demands for each scenario were quantified based on historical tendencies, narrative information derived from the workshop, and future Scottish Government targets. Results highlight trade-offs between forest cover, grasslands, natural areas including marginal peatlands important for carbon sequestration, and cropland for food production and the drinks industry. We discuss these preliminary findings, highlight key areas of uncertainty and present pathways for future work.