Thermal effect of the greens on the urban living environment

草地热环境的物理特征：对不同大小的草地进行了热环境测量，并与不同的地表材料进行了比较。在白天，各种地表物质的温度都在下降，直到200厘米，这种垂直温度廓线表明向上的热流或使空气变暖。另一方面，夜晚的草地上温度在上升，而沥青路面上的温度则像白天一样在下降。这表明草地表面在夜间充当冷源。在两个大型草地表面上测量了水平温度分布。温度在中心部分比在周边低。这种趋势在夜间更为显著，导致最大温差超过1度。考虑到在城市地区的沥青铺装停车场的数量，这些结果导致的建议，绿色停车场或绿色覆盖地下停车场作为有效的城市环境设计，以减缓城市变暖。评价室外热环境的热指标：进行了主观实验，在树荫下的裸露地面和阳光下的沥青路面。两个暴露空间的地球仪温度、地表温度和太阳总辐射差异较大，而空气温度和相对湿度差异较小。温度感觉与舒适感有很高的相关性。与温度感觉相关性较好的热力指标有地球仪温度、热带夏季指数和标准有效温度，其中前两者的相关性也较好。这表明，地球仪温度是一个有用的指标，评价室外热环境，考虑到易于测量。

Physical characteristics of thermal environment over the grasses :Measurements of thermal environment over the grass with various sizes were conducted, compared with different ground surface materials. The temperature was decreasing upward to 200cm over all kinds of surface materials in the day ; this vertical temperature profile indicates upward heat flow or warming the air. On the other hand, the temperature was increasing over the grasses at night, while it was decreasing over the asphalt like in the day. This suggests that the grass surface acts as the cool source at night. Horizontal temperature distribution was measured over two large grass surfaces. Temperature was lower at the central part than in the peripherials. This tendency was more remarkable at night, resulting in the maximum differential over 1 degree. Considering a number of asphalt-paved parking lots in the urban area, these results lead to recommendation of the green parking lots or the green coverages by undergrounding parking lots as effectual urban environmental design for mitigating the urban warming.Evaluation of outdoor thermal environment by thermal indices :Subjective experiments were conducted in the treeshade on the bare ground and in the sunshine on the asphalt pavement. There was great difference in globe temperature and ground surface temperature as well as general solar radiation between the two exposure spaces, though little difference in air temperature and relative humidity. Temperature sensation has high correlation with comfort sensation. Thermal indices that show high correlation with temperature sensation are Globe Temperature, Tropical Summer Index, and Standard Effective Temperature, among which the former two have similarly good correlation. This indicates that globe temperature is a useful index for evaluating outdoor thermal environment, considering easy measurement.