Arup has created a series of visualisations capturing London’s urban heat island effect during the recent heat wave.
The simulation has been done using data acquired through Earth observation satellites and the Geographic Information System (GIS) software.
Knowing which parts of the city are heating up the most during spells of hot weather could help improve the urban planning and retrofitting of residential areas in the future.
“During a heat wave, the Urban Heat Island effect prevents the city from cooling down at night, and means people aren’t able to escape the heat, especially in areas without many trees or green spaces,” said Polly Turton, senior technology consultant at Arup. “The UHI is clearly more of an issue in summer but this is likely to become more pronounced due to climate change,” she said.
Working jointly with the University College London scientists, the team has used data provided by the UK Space Agency. These remote sensing data have been fed into the GIS system, creating detailed maps capturing the differences in surface and air temperatures across Greater London. The images show clearly that there could be an up to 6°C difference between air and land temperatures of downtown areas and the rural suburbs.
“GIS technology is a great way to collate, analyse and visualise complex data for any location,” Turton said. “In this instance, by recognising patterns and connections in the data, we can start to identify ‘hot spots’ and ‘cool spots’ in urban areas, so that we can adapt our city to better face hot weather now and in the future.”
The UHI is caused mainly by the characteristics of materials used in construction of building and streets in the dense cityscape. The accumulation of heat is further increased by traffic pollution and the heat released from waste.
“The next stage of Arup’s Urban Heat Risk Mapping project will look at correlations between land and air temperature, population density, areas of deprivation, building heights and land use,” said Damien McCloud, GIS associate in Arup.
The researchers believe the studies could make future summers of the city dwellers a bit more bearable.