Paul Preston (United Kingdom) 1; Gina Cavan (United Kingdom) 1; Rachel Dunk (United Kingdom) 1; Graham Smith (United Kingdom) 1
1 - Manchester Metropolitan University
Urbanisation and urban densification alter urban structure, land use and land cover, for example through replacement of vegetated areas with impervious construction materials. This in turn can alter the energy balance in urban areas and lead to increased heat storage, exacerbating the Urban Heat Island (UHI) effect. These changes to land cover can also cause modifications to hydrological processes and increase surface runoff of rainwater through reducing evapotranspiration, reducing infiltration of water to the soil, and reducing the capture of rainfall. As climate risks such as heat waves, and pluvial flooding are pressing issues in cities, the understanding of factors that can influence urban resilience is of particular importance.
The presence of brownfield land (previously developed land that lies vacant or derelict and requires intervention to return the land into productive use) can provide islands of spontaneous vegetation succession, which are extensively distributed across many urban landscapes. While these sites likely provide climate regulating ecosystem services and positively impact upon urban climate resilience, they are now under developmental pressure in many cities. This research presents a new approach for the city-scale assessment of brownfield land, and its contribution to climate resilience.
Here we present a novel brownfield typology, based on land cover characterisation, and transferable to other post-industrial cities, that has been developed and locally adapted to the study area of Greater Manchester (GM), UK. An assessment of current brownfield land was undertaken using the evaluation of several criteria based on land cover classification using aerial imagery, spatial metrics, and various geospatial and topographical datasets, in order to produce a comprehensive characterisation of GM brownfield sites. This assessment found that a significant proportion of GM brownfield was vegetated and contained pervious surfaces or water bodies, indicating that such land is currently playing an important role in delivering climate regulating ecosystem services. Implications of the findings for climate resilience are further discussed.
This presentation will be of interest to spatial planners, environmental managers and practitioners, enabling a holistic overview of urban land in order to more effectively address brownfield redevelopment to support building climate resilience, and importantly, these methods can be applied to other cities around the globe.