Green infrastructure as an adaptation approach to tackling urban overheating in the Glasgow Clyde Valley Region, UK

Abstract Although urban growth in the city of Glasgow, UK, has subsided, urban morphology continues to generate local heat islands. We present a relatively less data-intense method to classify local climate zones (LCZ) and evaluate the effectiveness of green infrastructure options in tackling the likely overheating problem in cold climate urban agglomerations such as the Glasgow Clyde Valley (GCV) Region. LCZ classification uses LIDAR data available with local authorities, based on the typology developed by Stewart and Oke (2012) . LCZ classes were then used cluster areas likely to exhibit similar warming trends locally. This helped to identify likely problem areas, a sub-set of which were then modelled for the effect of green cover options (both increase and reduction in green cover) as well as building density options. Results indicate green infrastructure could play a significant role in mitigating the urban overheating expected under a warming climate in the GCV Region. A green cover increase of approximately 20% over the present level could eliminate a third to a half of the expected extra urban heat island effect in 2050. This level of increase in green cover could also lead to local reductions in surface temperature by up to 2 °C. Over half of the street users would consider a 20% increase in green cover in the city centre to be thermally acceptable, even under a warm 2050 scenario. The process adopted here could be used to estimate the overheating problem as well as the effectiveness green infrastructure strategies to overcome them.

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