Image Credit:

A melt water river formed by glacier melt in Greenland, Museum of Science and History, Chicago, James Balog

The official definition is ‘the fraction of incoming light that Earth reflects back into space’

In human terms, wearing a light shirt on a hot day will keep you cool, as it reflects heat back away from you. If you wear a dark shirt, it will make you warmer, as it absorbs more heat.

Okay, so why is this important?

Albedo has a huge effect on sea ice melting, especially in the Arctic and the Antarctic.

Sea ice is white, and the surrounding water is dark.

This means that the water around the ice will absorb more heat, and this speeds up melting of the ice.

The lighter ice will reflect more, and this helps it maintain itself.

When more ice melts, it changes how much light is reflected.

How? It’s simple. The more dark water is around sea ice, the faster the sea ice melts, which decreases the albedo. 

As the sea and land ice melt from within, rivers of meltwater form, which heats the ice from within.

This then causes the remaining ice to melt faster, and this cycle feeds itself.

Okay, how does this affect me?

We will talk about that in the next blog!

For now, white for summer, dark for winter!