Which process initiates enhanced glacial erosion and cirque formation in arctic mountains subject to freeze-thaw cycles?

💡 Explanation

When arctic mountains undergo freeze-thaw cycles, nivation—repeated ice wedging—occurs because water expands upon freezing, exerting pressure in rock fractures, initiating enhanced glacial erosion in cirques. Therefore, nivation is the answer, rather than abrasion, plucking, or striation which involve different mechanisms of glacial erosion and transport.

• Which mechanism causes increased ocean atmospheric CO2 absorption during coastal upwelling events?
• Which risk increases when extensive vegetation removal occurs on river levees?
• Which outcome occurs when the hydraulic gradient decreases sharply along a river flowing into a lake?
• Which risk increases when mountain streams fed by glacial melt reach elevated temperatures?
• Which process reduces the effectiveness of cirque glacial erosion in slowly deforming mountains with heterogeneous bedrock composition?
• Which phenomenon causes offset drainage patterns where streams cross a transform fault boundary?