The expansion of megapolitan regions, such as the Arizona Sun Corridor, could result in regional temperature rises of up to four degrees Celsius by 2050, reports a study published online this week in Nature Climate Change. These findings contribute to the understanding of urban heat islands - increased temperature in urbanized centres relative to the surrounding region - and the effectiveness of new technologies to counter this effect.
Matei Georgescu and colleagues modelled urban expansion in the Sun Corridor of Arizona. They find that temperatures and hydrological balances are affected by urban expansion, with diurnal temperature ranges narrowing. Temperature increases are dependent on the type of urban development, but are typically greater than one degree Celsius. However, installation of cool roof technologies can significantly reduce the warming effect.