polar glacier
Học thuậtThân thiện
Definition
Noun: A glacier that exists in a polar climate, typically near the Arctic or Antarctic poles, where the temperature remains so low that the ice is predominantly below the freezing point throughout the year, resulting in minimal melting.
Usage
This term is used in scientific and geographical contexts to classify glaciers based on their thermal regime and location. It specifies a glacier that is frozen to its bed and experiences little to no surface melt, even in summer.
Examples
- The Greenland Ice Sheet contains many polar glaciers.
- Scientists study polar glaciers to understand past climate conditions.
- Unlike temperate glaciers, a polar glacier has no significant meltwater layer at its base.
Advanced Usage
- In thermal classification: In glaciology, glaciers are often categorized by their temperature. A 'polar glacier' is contrasted with a 'temperate' or 'warm-based' glacier, which is at the melting point throughout.
- As a climate indicator: The stability and mass balance of polar glaciers are critical indicators of climate change in the Earth's coldest regions.
Variants and Related Words
- Cold-based glacier: A synonym often used in scientific literature to describe a glacier frozen to its bed, typical of polar regions.
- Ice sheet: A mass of glacial ice that covers surrounding terrain; polar glaciers are often components of or exist near continental ice sheets.
- Ice cap: A smaller, dome-shaped mass of ice covering a highland area; many ice caps in the Arctic are composed of polar glaciers.
Synonyms
- Cold glacier
- Cold-based glacier
- High-polar glacier (for emphasis on extreme cold)
Antonyms
- Temperate glacier
- Warm-based glacier
- Subpolar glacier (a transitional type with some melting)
Noun
- a glacier near the Arctic or Antarctic poles