Topography of the Arctic: Ice, Tundra, Mountains & Sea

The Arctic (north of 66.5°N) spans an ocean surrounded by continents—creating unique, interconnected landscapes:

1. Polar Ice Caps & Sea Ice

• Arctic Ocean ice pack: Seasonal (14M km² winter → 4M km² summer). Multi-year ice declining rapidly.
• Greenland Ice Sheet – 1.7M km², 3 km thick. Major freshwater reserve.
• Ice caps/glaciers: Svalbard, Franz Josef Land, Severnaya Zemlya, Canadian Arctic Archipelago, Iceland.

2. Tundra

• Treeless, permafrost-underlain (continuous/discontinuous).
• Vegetation: mosses, lichens, sedges, dwarf shrubs, wildflowers (short growing season).
• Carbon store: vast organic matter in frozen soils—thawing releases GHGs.

3. Mountains & Plateaus

• Brooks Range (AK) – 1,100 km, barrier between Arctic/boreal.
• Ural Mountains (RU) – Europe/Asia divide, northern extent.
• Scandinavian Mountains (NO/SE) – Fjords, plateaus.
• Innuitian Mountains (CA) – Ellesmere, Axel Heiberg; nunataks.
• Plateaus: Canadian Shield, Siberian (Putorana), Yana-Kolyma.

4. Fjords & Coasts

• Glacially carved: Norway, Greenland, Baffin Island, Svalbard.
• Steep walls, deep basins, sill-limited circulation.
• High productivity—marine mammals, seabirds.

5. Arctic Ocean Bathymetry

• Lomonosov Ridge – 1,800 km transpolar ridge (Eurasian vs. Amerasian Basins).
• Gakkel Ridge – Ultraslow spreading center, hydrothermal vents.
• Shelves: Barents, Kara, Laptev, East Siberian, Chukchi, Beaufort—broad, shallow.

6. Lakes & Rivers

• Thermokarst lakes (permafrost thaw).
• Major rivers: Yukon, Mackenzie, Lena, Ob, Yenisey, Kolyma—discharge peaks spring freshet.
• Delts: Lena (largest Arctic delta), Mackenzie.

7. Volcanoes

• Iceland (Mid-Atlantic Ridge), Kamchatka (Ring of Fire), Alaska (Aleutians/Wrangell), Jan Mayen.
• Subglacial eruptions → jökulhlaups (glacial outburst floods).

Climate Change Impacts

• Arctic amplification: warming 3–4× global avg.
• Sea ice loss, permafrost thaw, greening tundra, shifting species, coastal erosion.

This fragile, dynamic topography regulates global climate—and is transforming before our eyes.