Why are currents on the western coast of continents relatively cold whereas eastern coasts warm?

- Wind Direction: Prevailing winds blow from east to west near the equator. This movement pushes surface water away from the western coasts of continents.

- Upwelling: As surface water is pushed offshore, deeper, colder water upwells and replaces it. Upwelling also brings nutrient-rich deep water to the surface, supporting diverse marine ecosystems.

- Coriolis Effect: The rotation of the Earth causes a deflection of ocean currents. In the Northern Hemisphere, moving water is deflected to the right (clockwise), reinforcing the movement of cold water towards the western coasts.

Eastern Coasts: Warm Currents

- Ocean Gyres: Large-scale rotating ocean currents form gyres in each ocean basin. Warm currents flowing from warmer equatorial regions towards higher latitudes often hug the eastern coasts of continents due to the gyre's circulation pattern.

- Absence of Upwelling: Eastern coasts generally experience weaker upwelling compared to western coasts. This allows warm surface water from the ocean's interior to reach and stay near the coast.

In summary, cold ocean currents tend to prevail along western coasts due to factors like prevailing winds, upwelling, and the Coriolis effect. On the other hand, eastern coasts often benefit from warm currents due to ocean gyres and reduced upwelling, making their waters warmer in comparison.