Urban morpho-material parameters in cities and their correlation with summer air temperatures

Abstract In order to determine and compare the efficiency of different urban cooling strategies in two Latin American cities (Mendoza, Argentina and Campinas, Brazil), 18 scenarios that modified their percentage of vegetation and albedo level in urban envelopment materials were analysed. The scenarios were simulated using a high-resolution microclimatic model -ENVI-met 3.1. The possible associations between variables were evaluated through Principal Components Analysis. The result showed that the percentage of vegetation and the average albedo of the urban opaque surfaces explain 71.5 % of the behaviours within the urban canyons in both cities. The increase in vegetation could decrease the average temperature in Mendoza by up to 2.0 ºC, while in Campinas by up to 5.0 ºC. Increasing the albedo level in the urban envelopment raises the air temperatures in high-density scenarios of Mendoza and Campinas by up to 1.0 ºC. However, in the case of high albedo scenarios in horizontal surfaces and low albedo in verticals, there were reductions of 2.0 ºC in the city of Mendoza and 3.0 ºC in Campinas.

摘要 为确定并对比阿根廷门多萨市与巴西坎皮纳斯这两座拉丁美洲城市的不同城市降温策略的降温效率，本研究分析了18组调整了城市围护材料植被占比与反照率水平的模拟场景。所有场景均借助高分辨率微气候模型ENVI-met 3.1完成模拟。本研究通过主成分分析(Principal Components Analysis)对各变量间的潜在关联进行了评估。结果显示，两座城市的城市峡谷内的气候表现有71.5%可通过植被占比与城市不透水表面平均反照率进行解释。提升植被占比可使门多萨市的平均气温最高下降2.0℃，而坎皮纳斯市的平均气温最高可下降5.0℃。提高城市围护结构的反照率水平，会使门多萨与坎皮纳斯两市高密度开发场景下的气温最高升高1.0℃。不过，若采用水平表面高反照率、垂直表面低反照率的场景配置，门多萨市的气温可降低2.0℃，坎皮纳斯市则可降低3.0℃。