Ishøyninger

Ishøyninger is a glaciological term used in Norwegian to describe localized elevations on the surface of an ice body, such as a glacier or an ice shelf. The concept corresponds to features commonly described in English as ice rises or hummocky surface highs and is of interest because it reflects the interaction between ice flow and underlying conditions.

Formation occurs where the ice encounters subglacial topography, bedrock highs, or variations in grounding status that impede flow and cause local thickening and surface bulges. They can also develop where floating ice interacts with bathymetric highs near margins, leading to flexure-induced uplifts and isolated surface highs.

Characteristics include appearing as isolated or clustered surface elevations with rough, hummocky textures. Their size can vary from a few meters to tens of meters in height, and they are often bordered by crevasse fields that form around the uplifted area.

Distribution and study: Ishøyninger are commonly observed in polar regions with extensive ice shelves or fast-flowing glaciers, such as Greenland and Antarctica. They are investigated using radar sounding and laser or radar altimetry, as well as surface surveys. Satellite data and airborne campaigns help map their geometry and relation to grounding lines and regional ice dynamics.

Importance: These features influence local ice dynamics, including flow velocity, crevasse patterns, and the stability and evolution of ice shelves, with implications for modeling ocean–ice interactions and sea-level rise.

Terminology: The Norwegian term is prevalent in Nordic glaciology; in international literature the English equivalent “ice rise” is more widely used. The term may be used in relation to similar phenomena caused by bed topography or grounding changes.