Sea Ice Extent
Definition
Sea ice extent refers to the total area of ocean covered by sea ice at a given time, and it is one of the most important environmental variables for Antarctic penguin species. Adelie and emperor penguins depend on sea ice for breeding, resting, and access to prey. Since satellite records began in 1979, Antarctic sea ice has shown complex regional trends: some areas have lost ice while others have temporarily gained it. In 2023, Antarctic sea ice reached record lows, raising urgent concerns about the future of ice-dependent penguin populations.
Related Terms
Fast ice is sea ice that is anchored ("fastened") to the coastline, ice shelves, or the sea floor and does not move with winds or currents.
A polynya is an area of persistent open water surrounded by sea ice, maintained by wind, ocean currents, or upwelling warm water.
Climate change is the dominant long-term threat to penguin species worldwide.
Related Species
Species where sea ice extent is especially relevant.
Frequently Asked Questions
What does sea ice extent mean in penguin biology?
Sea ice extent refers to the total area of ocean covered by sea ice at a given time, and it is one of the most important environmental variables for Antarctic penguin species. Adelie and emperor penguins depend on sea ice for breeding, resting, and access to prey. Since satellite records began in 1979, Antarctic sea ice has shown complex regional trends: some areas have lost ice while others have temporarily gained it. In 2023, Antarctic sea ice reached record lows, raising urgent concerns about the future of ice-dependent penguin populations.
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Glossary entries define the language. FAQ answers common questions; guides carry the longer Survival Lab arguments.
More in ecologyWhere this definition comes from
Reference bodies behind the ecology terminology. Links last checked August 5, 2026.
- NOAA Fisheries - Marine food webs, climate, and ocean ecosystem context.
- British Antarctic Survey - Antarctic penguin ecology, diving, and sea-ice context.
- BirdLife Data Zone - Species accounts, distribution, and population summaries.