Uneven Distribution: Local Albedo

At this point, it is good to note that the light from the sun doesn't hit the Earth's surface evenly.

Source: Nature Education 

Over some parts of the Earth, the same amount of sunlight covers a larger area due to the spherical shape of the planet (also see picture above). This is one of the principal drivers of climate differences between different latitudes, and why it's warmer at the equator than at the North Pole.

This relates to albedo as well: Even though snow may have an albedo of up to 0.8 for pristine snow, the amount of light reflected back is still not very much because it was never a lot to begin with. Conversely, a tropical forest is dark, shady and absorbs a lot of sunlight. Its albedo will never be more than 0.2. Nevertheless, because the amount of incoming sunlight at the equator is so high, the absolute amount of reflected light might be more than at the poles. Local differences such as these can impact the planet's total albedo.

On average, the albedo of the planet Earth is about 0.39, even though the oceans have a far lower albedo and cover most of the surface. Clouds are an important contributor: as white sheets floating in the sky, they play an important role in returning sunlight before it has even hit the ground (a situation that can only too often be observed in real life in London).

More will follow soon on clouds, forests, deserts and other local albedo factors.