地理教学中关于日出日落方位的探讨

Discussion on Azimuth of Sunrise and Sunset in Geography Teaching

在高等师范院校地理教学实践中,有关日出日落方位是一个较难理解且经常被学生提到的问题。本文首先对教材的基本概念如方位、圆圈系统等进行梳理,结合地球的自转和公转,对日出日落方位进行了阐述和推理,详细地说明了为何夏半年日出东北、日落西北,冬半年日出东南、日落西南的问题。最后,运用球面三角的方法,对日出日落的准确方位进行了计算并分析了与日出日落方位有关的要素。

Azimuth of sunrise and sunset is a very important and difficult content which is often referred by the students during the lecturing of college geography.In this paper, the author reviews some basic terminologies and circles of spherical coordinates firstly. Combined with the earth rotation and the earth revolution, the principle of azimuth of sunrise and sunset is explained and illustrated.De-tailed explanation is given on why sunrise from northeast and sunset from northwest during summer half year and sunrise from southeast and sunset from southwest during winter half year in northern hemisphere.Finally, spherical trigonometry is used to calculate accurate az-imuth of sunrise and sunset.Declination of the sun and latitude of the studied area are two key influential factors to the change of azimuth of sunrise and sunset.