黄土高原山地城市延安的热岛效应

The heat island effect of the loess in Yanan

利用延安城市站与延长农村站1969—2008年气温资料,分析了热岛效应对延安气温的影响。结果表明:延安城市发展对年平均气温的影响可分为三个阶段,1992年以前,延安站温度未受影响,1993—2002年,城市影响较轻,年平均气温的热岛效应增温贡献率为38.1%,2003年以后,热岛效应明显,增温在1℃以上,与大城市的热岛增温接近。热岛效应增温对四季温度的影响基本一致,热岛效应增温与自然增温贡献率相等。城市热岛效应对最低气温的影响开始时间早,影响程度高,对年平均最高气温基本无影响。受热岛效应影响,不但提高了城市的温度同时也改变城市的增温率,使得城市气温增温率加大。

The effect of heat island on temperature was analyzed,utilizing the temperature data of Yanan city station and Yanchang county station from 1969 to 2008.It is found that the effect of Yanan urban development on the annual average temperature can be divided into three stages： the temperature has not been affected before 1992,and it＇s only a few from 1993 to 2002,the annual average temperature of the heat island effect contributed to 38.1%,after 2003 the heat island effect is obvious,more than 1 ℃,close to major cities.Heat island effects of warming temperatures in the four seasons are basically the same,heat island warming and the contribution rate are equal to the natural warming.The effect of urban heat island on the minimum temperature starts earlier,and effects are great,but it has no effect on the annual average maximum temperature.Affected by the heat island effect,not only the city temperature but also the city warming rate made the city increase the rate of warming temperatures.