deglaciation

climatology

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June 25, 2026

Quick Summary

Deglaciation refers to the melting of ice, specifically the retreat of glaciers or ice sheets. This process is a key aspect of Earth's climate history, particularly during the transition between glacial and interglacial periods.12

The last deglaciation began around 20,000 years ago, with the most rapid melting occurring between 14,000 and 6,000 years ago. This melting caused sea levels to rise significantly, by about 120 meters (390 feet) compared to today's levels at the peak of the last glacial stage. During this time, continental ice sheets, such as the Laurentide Ice Sheet in North America, completely disappeared.23

These climatic shifts led to unique environmental conditions with no modern analogs, influencing vegetation, animal distribution, and atmospheric circulation patterns. The Earth system has alternated between glacial and interglacial states for over two million years, driven by orbital variations and amplified by feedback mechanisms within the Earth system.24

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Antarctica
Glaciation
…Ice Sheet may have undergone deglaciations perhaps similar to those that occurred later during interglacial stages in the Northern Hemisphere. Evidence of former higher sea levels found in many areas of the Earth seems to support the hypothesis that such deglaciation occurred. If Antarctica’s ice were to melt today, for…
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…Ice Sheet may have undergone deglaciations perhaps similar to those that occurred later during interglacial stages in the Northern Hemisphere. Evidence of former higher sea levels found in many areas of the Earth seems to support the hypothesis that such deglaciation occurred. If Antarctica’s ice were to melt today, for…
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climate change
The last deglaciation
The continental ice sheets began to melt back about 20,000 years ago. Drilling and dating of submerged fossil coral reefs provide a clear record of increasing sea levels as the ice melted. The most rapid melting began 15,000 years ago. For example, the southern…
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The continental ice sheets began to melt back about 20,000 years ago. Drilling and dating of submerged fossil coral reefs provide a clear record of increasing sea levels as the ice melted. The most rapid melting began 15,000 years ago. For example, the southern…
Read More