Albedo of the Earth

The term albedo (Latin for white) is commonly applied to the overall average reflection coefficient of an object. For example, the albedo of the Earth is 0.37 (de Pater and Lissauer) and this affects the equilibrium temperature of the Earth. The greenhouse effect, by trapping infrared radiation, can lower the albedo of the earth and contribute to global warming.

‘反照率’（拉丁语中意为‘白色’）通常用于描述物体的整体平均反射系数。例如，地球的反照率为0.37（de Pater和Lissauer），这会影响地球的平衡温度。温室效应通过捕获红外辐射，可以降低地球的反照率，并加剧全球变暖。

The albedo of an object will determine its visual brightness when viewed with reflected light. For example, the planets are viewed by reflected sunlight and their brightness depends upon the amount of light received from the sun and their albedo. Mercury receives the maximum amount of sunlight, but its albedo is only 0.1 so it is not as bright as it would be with a higher albedo.

一个物体的反照率将决定它在反射光下视觉上的亮度。例如，行星是通过反射阳光被观测到的，它们的亮度取决于从太阳接收到的光量以及它们的反照率。水星接收到的阳光最多，但其反照率仅为0.1，因此其亮度不如具有更高反照率时那样明亮。

In more technical treatments of albedo, such as that of de Pater and Lissauer, a distinction is made between "bond albedo" and "geometric albedo", the numbers quoted above being geometric albedos. The geometric albedo is defined as the amount of radiation relative to that from a flat Lambertian surface which is an ideal reflector at all wavelengths. The bond albedo is the total radiation reflected from an object compared to the total incident radiation from the Sun. The bond albedo for the Earth is given as 0.29 by de Pater and Lissauer, compared to their value of 0.37 for the geometrical albedo.

在更技术性的反照率处理中，如de Pater和Lissauer的处理，区分了'bond albedo'和'geometric albedo'，上述引用的数值属于geometric albedo。geometric albedo定义为相对于一个平坦的兰伯特表面（在所有波长上都是理想反射体）的辐射量。而bond albedo则是将天体反射的总辐射量与太阳照射的总辐射量进行比较。de Pater和Lissauer给出的地球bond albedo为0.29，与他们给出的geometric albedo值0.37相比。

The planetary albedos given by de Pater and Lissauer are summarized in the following table: