Climate Change Global Digest Spring 2020
Photo by Markus Spiske on Unsplash
EXPANDING OUR URBAN DESIGN ANALYSIS
The analysis stage of any urban design project is critical to steering the guiding principles as well as the character of the solution that emerges at the end. As urban designers we aim to be as comprehensive as possible in our baseline evidence gathering, but many of us have been grappling with capturing climate change information at this baseline stage. However, an increasing number of data sources are coming to our aid. In this quarter’s climate change digest, we flag up useful data and maps that urban designers can now draw on to better support the climate change and environmental side of their baseline analysis.
UNDERSTANDING THE FUTURE CLIMATE OF URBAN AREAS
The Met Office has evolved its UK Climate Projections (UKCP) with the release of a new data set: UKCP Local. The key novelty is that the local grid is now 2.2km rather than 12km, and this means greater recognition of urban areas where the dataset is better able to present the heat island effect. The urban heat island effect arises from the different terrain characteristics of cities (such as reflectivity and the friction effect of surfaces), the ability of buildings to absorb heat by day and release it by night, and the energy dissipated within cities from human activities. This is a subject currently being explored by the UDGhosted EDGE debates.
On the theme of understanding future climate scenarios for different urban areas, there have also been some very useful comparator studies completed in the last year. A study published in 2019 sought to pair over 500 global cities to illustrate how the climates of each will change by 2050. The study found that over 75 per cent of cities are ‘very likely to experience a climate that is closer to that of another existing city than to its own current climate’. The remainder will experience climate conditions ‘that are not currently experienced by any existing major cities’. The study provides a real sense of the changes that each city will have to contend with by finding its closest future comparator; this means that in 2050 London will experience a climate much more similar to that of Barcelona. Whilst that might sound positive, the consequences would be significant for the city’s built fabric and infrastructure, including such major issues as the over-heating of the existing building stock.
For designers working in North America, one study has gone beyond global cities and has mapped the comparator climate for over 500 urban areas in the US. A great interactive app allows you to click on any urban area and find out which other one currently experiences the climate that it will have in 2080. For example clicking on Los Angeles draws a line to Las Palmas in Mexico where it is nearly 80 per cent drier.
We are not aware of a similar study of UK urban areas, but will keep you posted if we find one!
EMBODIED CARBON DATA
For many urban design studies, it would be fantastic to be able to understand the embodied carbon of the existing built fabric. Such an understanding would allow designers and clients to make more informed decisions on whether to refurbish or demolish certain buildings. Two sign-up databases exist to provide the data to enable such an analysis to be undertaken. Firstly, the Inventory of Carbon and Energy (ICE) Database which is the world’s leading source of embodied energy and carbon data and is available for free.
Secondly, the Royal Institute of Chartered Surveyors’ database also provides a free and publicly available resource on the embodied carbon of different materials and buildings, from which estimates can be made for existing buildings.
Data on open spaces and nature reserves is often easily available from public sector clients or via websites such as MAGIC. However, the availability of data on trees is often more tricky to source. The Forestry Commission now provides an interactive map (with downloadable GIS layers) for tree canopy cover for most areas.
Air pollution data is also increasingly easily accessible for urban areas. Some useful websites are now drawing together data sets on a number of factors to provide an interesting overview of the environmental experience of places. The Consumer Data Research Centre for example combines data on air pollution, access to blue and green space, as well as access to health and retail services.