2015 · GS Paper 1 · Q14 · 12 marks
Explain the factors responsible for the origin of ocean currents. How do they influence regional climates, fishing and navigation?
In short
Ocean currents originate from planetary winds, the Coriolis force, density differences and the shape of coasts, and they redistribute heat, nutrients and risk. The North Atlantic Drift keeps Murmansk ice-free, while the Grand Banks meeting of warm and cold currents breeds fish but also fog.
Model answer
Ghissu Editorial · Verified 4 Oct 2026 · 265 words
Planetary winds
The trade winds and westerlies drag surface water into the equatorial currents and the North Atlantic Drift, and the monsoon reverses north Indian Ocean currents each season.
Coriolis force
Earth's rotation deflects currents right in the northern hemisphere and left in the southern, forming gyres.
Density and coastlines
Cold, saline water sinks in the Labrador and Weddell Seas to drive the thermohaline circulation, while coasts like Cape Sao Roque split and steer currents.
Regional climates
The North Atlantic Drift keeps Murmansk ice-free, while cold currents dry west coasts, helping create the Atacama beside the Humboldt and the Namib beside the Benguela.
Fishing
Warm-cold mixing of the Gulf Stream and Labrador Current off Newfoundland's Grand Banks breeds plankton, and Humboldt upwelling sustains Peru's anchoveta fishery until El Nino suppresses it.
Navigation
Ships save time and fuel by riding currents, as sailing ships once rode the trade-wind currents, but the Grand Banks meeting zone brings dense fog and the Labrador Current carries icebergs, the hazard that sank the Titanic in 1912.
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Water (Oceans)4 questions
Asked in 4 of 14 sittings since 2013
- 2022What are the forces that influence ocean currents? Describe their role in fishing Industry of the world.
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Question from the official UPSC Civil Services (Main) Examination 2015 paper. Answer written by Ghissu's engine and checked against our editorial standards. Found an error? Tell us and we correct it within 48 hours.