The Nature & Distribution Of Cold Environments Flashcards
What are the inputs, outputs, stores, and flows in a glacial system? (4 things)
• Inputs: Snow, avalanches, weathering debris, solar radiation.
• Outputs: Meltwater, sediment, erosion, deposition, reflection of solar radiation.
• Stores: Ice masses (glaciers, ice caps, ice sheets), moraines, meltwater lakes.
• Flows: Glacial movement, sediment transport, meltwater flow.
What is the difference between glacial and periglacial landscapes?
• Glacial landscapes: Formed by glacier movement (erosional & depositional features).
• Periglacial landscapes: Cold environments where ice plays a role but glaciers are absent.
What is a feedback mechanism in glacial systems? (2 things)
• Positive feedback: Melting glaciers cause further warming, leading to more melting.
• Negative feedback: Increased snowfall adds weight, pushing glaciers downslope, balancing ice loss.
What are the 3 different types of ice cover?
• Ice sheets: Large, dome-shaped masses covering landscapes (e.g., Antarctica, Greenland).
• Ice caps: Smaller ice sheets covering highlands (e.g., Svalbard).
• Ice fields: Ice sheets covering mountain plateaus (e.g., Vatnajökull, Iceland).
What are the two main types of glaciers?
• Valley glaciers: Ice tongues confined to valleys (e.g., Athabasca Glacier, Canada).
• Cirque glaciers: Small glaciers in mountain hollows (e.g., Swiss Alps).
What are the 2 thermal characteristics of glaciers?
• Cold-based glaciers (polar glaciers): Frozen to bedrock, minimal movement (e.g., Antarctica).
• Warm-based glaciers (temperate glaciers): Water at the base allows movement (e.g., Alps).
Where is ice found today? (2 things)
• High latitude: Arctic & Antarctic Circles, where solar radiation is weakest.
• High altitude: Mountain ranges like the Andes, Himalayas, and Alps.
How has ice distribution changed from the Pleistocene to today? (3 things)
• Antarctica: 14.5 million km² (Pleistocene) → 13.5 million km² (today).
• Greenland: 2.4 million km² (Pleistocene) → 1.8 million km² (today).
• Scandinavia: 6.6 million km² (Pleistocene) → 0.004 million km² (today).
What are the 3 Milankovitch Cycles?
• Eccentricity (stretch): Earth’s orbit shifts between circular and elliptical, altering solar radiation.
• Obliquity (tilt): Earth’s axis tilts between 21°-24°, affecting sunlight distribution.
• Precession (wobble): Earth’s axis wobbles, changing its distance from the Sun.
How do volcanic eruptions impact climate? (2 things)
• Volcanic eruptions release ash, SO₂, CO₂, and water vapour.
• These block solar radiation, cooling the Earth (e.g., Mount Pinatubo, 1991).
What are sunspots, and how do they affect climate?
• Sunspots are temporary increases in solar radiation output.
• They follow an 11-year cycle, increasing Earth’s energy by 0.1%.
What are Icehouse and Greenhouse Earth periods?
• Icehouse Earth: Cold periods with extensive ice cover.
• Greenhouse Earth: Warm periods with little or no ice.
What are the Pleistocene and Holocene epochs?
• Pleistocene (2.6 million – 12,000 years ago): Multiple glacial and interglacial periods.
• Holocene (12,000 years ago – present): Warmer interglacial period with retreating ice.
What was the Little Ice Age? (Give 2 things)
• Occurred in the late 15th to 18th century.
• Temperatures dropped 1°C lower than today, causing rivers like the Thames to freeze.
What is the Anthropocene, and why is it significant?
• A proposed new geological era where human activity is the dominant force altering Earth’s systems.
