What is Permafrost? - Anita

• Permafrost, despite its name, is not always frozen ice.
• Soil composition, the presence of salt, and some other factors can keep some ground from actually freezing, even as the temperature remains below freezing point.
• Across much of Alaska, Canada, Russia and Antarctica, the ground is the fact frozen year - round, however, to depths of as much as 5,000 feet.
• A relatively thin layer near the top may be subject to a yearly freeze - thaw cycle, allowing ground vegetation to survive.
• As the planet warms, the effect of a meltdown in permafrost areas is a subject of debate.
• Some have speculated , for example, that a widespread thaw would release massive amounts of greenhouse gases now trapped in the permafrost into the atmosphere, further warming the planet.