isbreene

Isbreene are large, persistent bodies of dense ice that form on land from the accumulation, compaction, and recrystallization of snow over many years. They move slowly under gravity, flowing and deforming, which sculpts valleys and other landscapes. The upper part gains mass through snowfall (accumulation), while the terminus loses ice through melting, sublimation, and calving (ablation). The boundary between accumulation and ablation is the equilibrium line; climate changes shift this line and cause glaciers to advance or retreat.

Glaciers are classified by shape and location: valley glaciers occupy mountain valleys; ice sheets cover wide continental areas (such as Greenland and Antarctica); cirque or bowl glaciers form in sheltered hollows; piedmont glaciers spread at valley mouths; tidewater glaciers terminate in the sea and can calve to form icebergs.

Glaciers erode and transport material, creating features such as U-shaped valleys, moraines, and fjords. They are sensitive indicators of climate change and contribute to sea-level rise when large ice masses melt or accelerate. Globally, glaciers store a substantial fraction of Earth's freshwater and provide meltwater for rivers in summer. Monitoring uses satellites, aerial surveys, and field measurements to track changes in length, area, volume, and mass balance.

In Norwegian, isbreene refers to the glaciers, with isbre the term for a glacier and isbreene the definite plural.