The thermal difference between the urban center of and its surroundings is known as the heat island effect. And in Madrid it is higher than that of other large cities such as Bombay (India), New York and Los Angeles (United States), Cairo (Egypt) and London (United Kingdom).
This is clear from the Urban Heat Snapshot study prepared by the company Arup, specialized in building, urban planning, civil and industrial engineering, design, project management and consultancy. The work released this August analyzes the effect of replacing the natural surface of the ground with roads, buildings and other materials that absorb heat, leaving very little water and vegetation to cool them.
Add to this the added heat from traffic, air conditioning and other human activities, and temperatures in more urban areas rise compared to their less urbanized surroundings. Something against the capital City Council is fighting by testing vertical gardens to try to mitigate the ravages of heat islands such as Calle 30 Natura, the pilot project that covers an area of 3,250 square meters and replaces the concrete walls of the M-30 with 23 species vegetables along the 400 meters that separate the roundabouts of Mariano Salvador Maella and Nueva Zelanda.
Using artificial intelligence and satellite images obtained from space, the study authors mapped the most extreme hot spots in a 150-square-kilometre sample of the urban centers of the six mentioned cities.
Arup used its digital analysis tool UHeat to learn the differences in air temperatures between neighborhoods on the hottest day in each city in 2022. Those areas were divided into 60,000-square-meter hexagonal blocks, allowing the difference in temperatures to be modeled of the air experienced that day and that night between the different neighborhoods.
Madrid registers the greatest variation in temperature between indoor and outdoor urban areas (8.5 degrees), ahead of Bombay (7.0), Cairo and Los Angeles (5.0), and London and New York (4.5 ).
Regarding Madrid, the researchers detected a difference of 8.5 degrees on the afternoon of June 15, 2022 between the Juan Pujol square, located in the Malasaña neighborhood and with 3% vegetation, and the north of the Casa de Campo , made up of 89% green surface.
