Where Glaciers are Located

If glaciers form from snow accumulation, why are glaciers not found everywhere it is cold and snowy?

The map shows some places where glaciers are located worldwide. How can you explain the presence of glaciers in tropical areas close to the equator, such as those in Africa and South America?

In tropical areas such as these, glaciers are found only on the highest mountains. These are high-elevation glaciers. They are located on mountains high above the snowline. For example, glaciers in Africa are found on the summit and upper slopes of Mt. Kenya and Mt. Kilimanjaro.

Remember that for a glacier to form, ice accumulation must exceed ablation. Also, glacial ice comes from snowfall. Some areas that are very cold, like Siberia, do not have glaciers because they simply do not have lots of snowfall even though it is cold. Other areas may have sufficient snowfall in the winter, but warm summers melt it away before a glacier forms.

Most glaciers exist in polar environments or in environments with high snowfall in the winter and cool summers that discourage melting. These high-elevation areas are classified as above the snowline. More snow accumulates in the winter than will melt in the summer in these areas. Most of the world’s glaciers are in Antarctica and Greenland, but glaciers are also found on every continent except Australia. They are also found on the large Pacific islands of New Zealand and Papua New Guinea.

On the map, areas in red and orange are areas of glacial retreat, while those in blue are areas of glacial growth, both since 1970. Why do you think there has been so much glacial retreat in the last few decades?

Many scientists believe that global warming is bringing warmer temperatures and changes in snowfall patterns that are resulting in worldwide glacial retreat.