♻️ap environmental science review

Permafrost

Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examWritten by the Fiveable Content Team • Last updated September 2025

Definition

Permafrost refers to permanently frozen ground consisting of soil, rock, or sediment that remains below 0°C (32°F) for at least two consecutive years. It is found mainly in polar regions but also exists in some high-altitude areas.