Albedo & Permafrost Positive Feedback – AP Environmental Science

Learning Objectives

Albedo Loop: Ice is highly reflective (high albedo). As it melts, dark ocean water (low albedo) is exposed, absorbing more heat, melting more ice.

Permafrost Loop: Frozen ground contains massive amounts of trapped methane (CH4) and organic carbon. Melting releases it, accelerating warming.

Positive Feedback: "Positive" here does NOT mean "good". It means the output of a system amplifies the initial change, pushing it further out of balance.

Tags

Climate ChangeAlbedoPermafrostMethane

Arctic Ice Albedo

Albedo = 0.85 (High Reflection)

Siberian Permafrost

Release Rate = 10 Tg CH4/yr

Global Temperature Anomaly

+0.0 °C

The Mechanism: As you increase the baseline temperature (forcing), observe how both physical systems respond. The melting ice drastically lowers reflectivity, while the thawing soil releases bubbling methane. Both actions serve to increase the temperature even further in reality.

AP Exam Tip

You must memorize that Methane (CH4) is ~25-80x more potent as a greenhouse gas than CO2 in the short term. The permafrost feedback loop acts as a ticking time bomb—once thawed, the microbial decay cannot be artificially frozen again.