Measuring the urban heat island effect on bike
Last August reseachers of Wageningen University (WUR) have been cycling through Arnhem and Rotterdam in the Netherlands on cargo bikes during and after hot summer days. Aim of the measurements was to measure the intensity of the Urban Heat Island effect. The measurements in Arnhem were done out of the Future Cities project.
The measuring was to study the Urban Heat Island (UHI) effect that often causes heat stress. The measurements showed that the city centers of Arnhem and Rotterdam were 2 to 3 degrees higher than area's outside the cities. A striking observation was that city parcs were cooler than aera's outsite the cities.This means that the differences in the afternoon in the city can rise to 4 to 5 degrees centigrade. These are differences that are quite normal for cities, based on scientific studies in other European countries or even Hong Kong.
During the late evening (22-24 hours) the maximum difference in temperature between the city centers and the countryside consequently amounted to more than 7 degrees during nocturnal hours. The most striking conclusion was that both Rotterdam and Arnhem show the same results. Knowing that Arnhem is much smaller than Rotterdam and has a complety different urban structure .. the need of further investigation seems legitimate.
For the measurements the researchers cycled along previously determined routes through a number of characteristic urban districts, such as industrial area's, older residential area's, the city centers, city parks and (for Rotterdam) the harbour area. The researchers plan to take more measurements in the years to come.