Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, China.
State Key Lab of Hydro-Science and Engineering, Tsinghua University, Beijing 100084, China.
Int J Environ Res Public Health. 2021 Feb 12;18(4):1790. doi: 10.3390/ijerph18041790.
Urban evaporation, as an essential part of local water vapor resources in urban areas, has often been underestimated. One possible reason is that the evaporation of urban hardened surfaces is seldom considered and poorly understood in urban evaporation estimation. This study focused on the mechanisms and calculation of evaporation on hardened surfaces in urban areas. Experimental monitoring was used to monitor the processes and characteristics of evaporation on hardened surfaces. Mathematical models based on water quantity constraints were built to calculate evaporation of hardened surfaces. The results showed that: The interception abilities for rainwater and rainfall days of impervious hardened surfaces determine their evaporated water amount, which means no water, no evaporation for the impervious surfaces. The greater evaporation of artificial sprinkling on roads happened in fewer days of rainfall and frost. The evaporation of pervious hardened ground is continuous compared to the impervious surface. Its soil moisture in the sub-layer of permeable concrete decreases periodically with a period of one day. The evaporation of hardened surfaces occupies 16-29% of the total amount of evaporation in the built-up areas in cities. Therefore, the hardened surface evaporation has great significance on the urban hydrological cycle and urban water balance.
城市蒸发作为城市地区局部水汽资源的重要组成部分，往往被低估。一个可能的原因是，在城市蒸发估算中，很少考虑和充分理解城市硬化表面的蒸发。本研究侧重于城市地区硬化表面蒸发的机制和计算。实验监测用于监测硬化表面蒸发的过程和特性。建立基于水量约束的数学模型来计算硬化表面的蒸发量。结果表明：不透水硬化表面的雨水截留能力和降雨天数决定了其蒸发水量，这意味着不透水表面没有水就没有蒸发。道路人工喷淋的蒸发量在降雨和结霜天数较少的情况下发生。与不透水表面相比，透水硬化地面的蒸发是连续的。其透水混凝土次层的土壤水分周期性地以一天为周期减少。硬化表面的蒸发占城市建成区总蒸发量的 16-29%。因此，硬化表面的蒸发对城市水文循环和城市水量平衡具有重要意义。
