Climate 101: Glaciers | National Geographic
Glaciers and Climate Change: An Overview
The Role of Glaciers in Shaping the Earth
- Glaciers have been instrumental in shaping landscapes for millions of years, but climate change is causing their rapid disappearance, impacting oceans, weather patterns, and life on Earth.
- There are two main types of glaciers: alpine glaciers, which form on mountainsides and move through valleys, and ice sheets that spread out from central domes across vast areas.
Types of Glaciers
- Ice sheets differ from alpine glaciers as they cover extensive regions including valleys and plains; the largest ones are known as continental glaciers.
- Major examples include the ice sheets covering most of Antarctica and Greenland. These glaciers form over time as snow accumulates and compresses into dense ice.
Formation Process
- The process begins with snow becoming denser over time; this compacted snow transforms into firn before fusing into glacial ice.
- As glaciers move under their own weight, they erode the land beneath them, creating various landscape features such as lakes and valleys.
Resources Provided by Glaciers
- Glaciers contribute to fertile soil (glacial till), materials for construction (sand and gravel), and vital freshwater resources for ecosystems.
Impact of Climate Change on Glaciers
- Rising global temperatures lead to melting ice sheets which contribute to rising sea levels while reducing freshwater availability for terrestrial life.