# 日照时长随地理纬度及季节的变化关系Analysis of the Variation of Photoperiod with Latitude and Season

Abstract: An analysis is conducted of the relation of the photoperiod on the earth with its rotation and rev-olution. The seasonal change of the photoperiod is also interpreted based on the mutual relation. Furthermore, upon analyzing the geometrical sun-earth relation as well as the day and night change on the earth, a formula is established to describe the relationship of the photoperiod and the observation location for any time of the year. With this formula, the seasonal and the geographical variation of the photoperiod can be predicted, and the phenomenon of the polar day and the polar night can be well interpreted. Finally, the formula has been applied to discuss the mean photoperiod of some representative cities in China in January and July. The prediction accuracy of the formula is evaluated upon comparing the calculated value of the photoperiod to the true value of Beijing.

[1] 高峰, 孙成权等 (2001) 太阳能开发利用的现状及发展趋势. 世界科技研究与发展, 4, 35-39.

[2] 刘南威 (2002) 自然地理学. 科学出版社, 北京.

[3] Cooper, P.I. (1969) The adsorption of radiation in solar stills. Solar Energy, 3, 333-346.

[4] Spencer, J.W. (1971) Fourier series representation of the position of the sun. Search, 5, 172.

[5] 叶瑜, 苏永秀, 李政, 王莹, 梁骏 (2013) 近50年广西日照时数时空变化特征分析. 中国农学通报, 14, 196-201.

[6] 何彬方, 冯妍, 荀尚培, 唐为安 (2009) 安徽省50年日照时数的变化特征及影响因素. 自然资源学报, 7, 145- 155.

[7] 徐宗学, 赵芳芳 (2005) 黄河流域日照时数变化趋势分析. 资源科学, 5, 153-159.

[8] 李慧群, 付遵涛, 闻新宇, 黄建斌 (2013) 中国地区日照时数近50年来的变化特征. 气候与环境研究, 2, 203- 209.

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