Cold and Warm Ocean Currents: Earth's Thermal Conveyor

Two Flows, One Climate System

Cold Currents

Carry polar/equatorial water toward the equator/poles. Found on western sides of ocean basins (eastern boundary currents).

• Humboldt (Peru) Current: N. along Chile/Peru → upwelling → rich fisheries.
• Canary Current: SW off NW Africa → cool, dry climate (Canaries, Sahara coast).
• Benguela Current: N. off SW Africa → upwelling, diamonds, fog (Namib).
• California Current: S. along W. North America → coastal fog, kelp forests.
• Oyashio Current: S. along Kuril/Kamchatka → subarctic nutrients.

Warm Currents

Carry tropical heat poleward. Found on eastern sides of basins (western boundary currents).

• Gulf Stream / North Atlantic Drift: Florida → Europe → keeps NW Europe 5–10°C warmer.
• Kuroshio Current: Japan → N. Pacific → similar warming for E. Asia.
• Brazil Current: S. along Brazil → subtropical South America.
• East Australian Current: S. along E. Australia → "Finding Nemo" highway.
• Agulhas Current: SW along S. Africa → retroflection leaks heat to Atlantic.

Global Impact

Redistribute ~50% of Earth's equator-to-pole heat. Drive weather, fisheries, carbon uptake, hurricane fuel. Climate change weakens AMOC (Gulf Stream system)—major tipping point risk.