The sky above Dexing, eastern China's Jiangxi province turned pink on Jan. 6, triggering concerns that the phenomenon might be caused by pollution. The sight was photographed by a local teacher.

The local department of environmental protection stated that the pink sky was unrelated to pollution. There are only two manufacturing enterprises in the region, neither of which discharges pollutants. According to an employee of the department, the meteorological phenomenon was a result of thick cloud cover and refraction.

The employee said the angle of sunlight is low in the morning and evening, and light with a shorter wave length (green, blue and purple light) is absorbed by moisture in the air. As a result, the sky turns pink due to the refraction of light with a longer wave length, such as red and orange. The phenomenon also appeared in southwestern China's Chongqing municipality two years ago.