How is glaciation best described?

Glaciation is best described as the expansion of glaciers covering land areas. This process involves the accumulation and compaction of snow that eventually transforms into ice, forming large masses known as glaciers. These glaciers can flow and move due to gravity, advancing and retreating over time, significantly shaping the landscape through erosion and deposition.

During glaciation periods, extensive areas of land can be covered by ice, leading to various geological features such as valleys, fjords, and moraines. The effects of glaciation are profound, influencing ecosystems, climate, and human activities over geological timescales. Understanding glaciation is crucial in geography as it helps explain past climate changes and landscape evolution.