Time.news – There is a “heat island” effect in big cities, writes Paìs. What does it mean? That asphalt and concrete absorb heat during the day and throw it back out during the night, thus making the temperature much higher than in adjacent places, where earth and trees predominate.
Nothing new so far, only that a study published in the Lancet magazine on February 1st which contains the data of 93 European cities, where 57 million inhabitants over the age of 20 live, “estimates that around 6,700 premature deaths” are due precisely to the phenomenon of “heat islands” and points out that a third of these same deaths could be avoided simply by planting trees in 30% of urban space.
However, the newspaper also explains that “it is important to differentiate the mortality attributable to ‘heat waves’, which can affect many more places, with that linked to ‘heat islands’, which are the effect of urban planning” based on “asphalt , concrete and lack of vegetation which increase the risk to health on summer days, even with normal temperatures”, the researchers point out.
The research model provides a result of premature deaths linked to the increase in temperatures in urban environments, which represents 4.3% of total mortality during the summer months (June to August) and 1.8% of mortality throughout the year. In any case, the authors believe that a third of them (about 2,644 deaths) could have been avoided by increasing the tree cover up to 30% of the urban space, which would reduce temperatures on average by almost half a degree, but in some places even by 1.5°C and maybe even more.
The wooded area of the cities analyzed is equal to 14.9%., but in general cities with the highest heat excess mortality rates are located in southern and eastern Europebeing those that would benefit most from an increase in tree cover.
According to Tamara Iungman, researcher at L’IsGlobal, an institution promoted by the La Caixa Foundation which conducted the study, Barcelona for example has only 8% trees and the premature mortality attributed to the heat island effect is 14%, while Madrid, which has 9.5% of forested area, has a mortality rate of about 12% for this very reason.
Paìs writes again that the document analyzes the urban space with high-resolution images (in areas of 250 meters by 250 metres) to also take into account the distribution of vegetation. “It is important to differentiate the mortality attributable to ‘heat waves’, which can affect many more places, with that linked to ‘heat islands’, which are related to urban design: asphalt, concrete and the lack of vegetation increase the health risk on summer days, even with normal temperatures”, the researchers point out.
The idea of the reference model published in the Lancet is to offer urban planners and local councilors tools for understanding the extent of the problem and the positive effect of changing the usual urban model with one that contemplates “greener”.