城市区域下垫面性质和位置差异对太阳辐射平衡的影响

INFLUENCES OF UNDERLYING SURFACE'S CHARACTERISTICS AND LOCATIONS ON SOLAR RADIATION BALANCE IN URBAN AREA

以低纬高原城市昆明为研究对象,利用城市区域内4月、8月、12月的太阳辐射观测资料,对城市区域内不同下垫面性质和位置差异的辐射平衡特征和变化规律进行了研究。结果表明:昆明地区4月的太阳辐射各分量均较高,而多云天气的8月太阳辐射分量较小;屋顶的总辐射量和净辐射量均维持较高的数值,而受周围环境、建筑物遮蔽等影响的草地和球场则数值变化较大;随时间和下垫面的不同,反射辐射呈现较大差异;有效辐射则在多云天的8月呈现较小值(分配率趋于0)。所得结果可为探讨城市气候形成机制及城市气候的深入研究提供依据,并为其它地区的研究提供参考。

According to observations of solar radiation in April, August and December in Kunming, a city situating in low latitude plateau, characteristics and variations of solar radiation balance are studied for underlying surface of different characteristics and locations in urban area. Results shows that the values of each radiation factor in the radiation equation are the largest in April, and smallest in August, when it is cloudy. For the total radiation and net radiation, they are largest on the rooftop, and fluctuate greatly on the ground and lawn due to the influences of the surroundings and building shading. The reflective radiations vary greatly with time and different surfaces. Meantime, the net long wave radiation is the smallest in August (the percentage in total is almost zero). These results not only can be served as scientific foundation for more research on urban climate and the mechanism for causing it, but also may be reference for studying the urban climate concerning other regions.