Cities are increasingly aware of the need to mitigate greenhouse gas emissions and adapt to changes in weather patterns leading to the production of urban climate change plans. The few existing systematic studies of these plans have focused on either adaptation or mitigation issues, and are typically based on surveys completed by city officials rather than analysis of documented evidence. To gain insight into the status of adaptation and mitigation action across the UK, climate change documents from 30 urban areas (representing ~28 % of the UK’s population) were analysed. An Urban Climate Change Preparedness Score, which could be applied to other urban areas outside the UK, has been devised for comparative analysis. This analysis characterizes progress against (i) Assessment, (ii) Planning, (iii) Action, and (iv) Monitoring, for both adaptation and mitigation. The Preparedness Score allows a quantitative comparison of climate change strategies across the urban areas analysed. This methodology can be transferred to other countries and makes an international comparison of urban areas and their climate change adaptation and mitigation plans possible. We found that all areas acknowledge climate change being a threat and that adaptation and mitigation planning and action is required. However, two urban areas did not have official adaptation or mitigation plans. Typically, mitigation activities across all cities were more advanced than adaptation plans. Emissions reduction targets ranged from 10 %–80 % with differing baselines, timeframes and scopes, for defining and meeting these targets. Similar variability was observed across adaptation plans. Several reasons for these differences are considered, but particularly notable is that a combination of incentives and regulation seem to stimulate more comprehensive strategies and action in many urban areas.

The urgent need to reconfigure and transform urban areas to consume fewer resources, emit less pollution, minimize greenhouse gas production, protect natural ecosystems and increase the adaptive capacity to deal with climate risks is widely recognized. The implementation of improved sustainability measures in cities requires integrated thinking that encompasses a whole range of urban functions, often implying a major restructuring of urban energy systems, transport and the built environment, as well as a new approach to the planning and management of natural systems that service urban areas. Many local governments have a limited capacity to deal with such complex and interrelated problems, and this hampers their ability to deal with climate change. With these issues in mind, teams of scientists, practitioners and stakeholders in Durban (led by eThekwini Municipality) and London (led by the Tyndall Centre for Climate Change Research) developed city-scale integrated assessment modelling tools that represent interactions between different urban functions and objectives by linking climate change issues to broader agendas such as spatial planning. This paper reviews each integrated assessment tool, and critically analyzes their effectiveness in terms of technical approach, extent to which they meet policy needs, role of stakeholders in model development and application, barriers to their uptake and the value of and effort required for integration. While these integrated assessment tools did not provide the detailed design information sought by some decision makers, importantly they have stimulated stakeholders to think strategically and hold cross-sectoral conversations around implementing sustainability measures. Despite the technical and institutional challenges associated with the development and uptake of an integrated assessment model, we conclude that they do contribute to the quest for urban sustainability.

Cities are faced with a number of sustainability challenges in the context of climate change. There is an urgent need to limit greenhouse gas emissions from cities if ambitious mitigation targets are to be met. Meanwhile, cities are vulnerable to the impacts of climate change unless adaptation plans can be put in place. The need to connect climate change adaptation and mitigation with broader assessment of sustainability is becoming increasingly recognised. This paper describes an urban integrated assessment facility developed by the Tyndall Centre for Climate Change Research, which simulates socio-economic change, climate impacts and greenhouse gas emissions over the course of the twenty first century at the city scale. The urban integrated assessment facility adopts a broad-scale systems approach to urban development and sustainability assessment. It incorporates a multi-sectoral model of the regional economy, hierarchical city-scale spatial interaction model and modules for assessment of climate impacts, adaptation options and greenhouse gas emissions. The paper demonstrates how the urban integrated assessment facility quantifies synergies and conflicts between adaptation to climate change and mitigation of greenhouse gas emissions in order to improve decision making and facilitate the development of portfolios of planning policies that together have a realistic prospect of achieving sustainable outcomes for cities.

The UKCIP02 climate change scenarios (2070–2100) suggest that the UK climate will become warmer (an overall increase of 2.5–3°C), with temperature increases being greater in the summer and autumn than in the spring and winter seasons. In terms of precipitation, winters are expected to become wetter and summers drier throughout the UK. The effect of changes in the future climate on flow regimes are investigated for the Atlantic salmon, Salmo salar, in a case study in an upland UK river. Using a hydraulic modelling approach, flows simulated across the catchment are assessed in terms of hydraulic characteristics (discharge per metre width, flow depths, flow velocities and Froude number). These, compared with suitable characteristics published in the literature for various life stages of Atlantic salmon, enable assessment of habitat suitability. Climate change factors have been applied to meteorological observations in the Eden catchment (north-west England) and effects on the flow regime have been investigated using the SHETRAN hydrological modelling system. High flows are predicted to increase by up to 1.5%; yet, a greater impact is predicted from decreasing low flows (e.g. a Q95 at the outlet of the study catchment may decrease to a Q85 flow). Reliability, Resilience and Vulnerability (RRV) analysis provides a statistical indication of the extent and effect of such changes on flows. Results show that future climate will decrease the percentage time the ideal minimum physical habitat requirements will be met. In the case of suitable flow depth for spawning activity at the outlet of the catchment, the percentage time may decrease from 100% under current conditions to 94% in the future. Such changes will have implications for the species under the Habitats Directive and for catchment ecological flow management strategies.