Ocean currents, tides, and the resources found within the world's oceans.
Ocean currents are large-scale movements of seawater, driven by wind, temperature/salinity differences (thermohaline circulation), and the Coriolis effect. Warm currents generally flow from the equator toward the poles, while cold currents flow from polar regions toward the equator, significantly influencing coastal climates — for example, the warm Gulf Stream moderates Western Europe's climate.
Tides are the periodic rise and fall of sea levels caused primarily by the gravitational pull of the Moon, with a secondary contribution from the Sun. Spring tides (higher highs, lower lows) occur when the Sun, Moon, and Earth align (during new and full moons); neap tides (smaller range) occur when the Sun and Moon are at right angles to each other.
Oceans provide vast resources — fisheries, minerals (like polymetallic nodules on the deep seabed), and energy potential (offshore oil and gas, tidal and wave energy). India's Exclusive Economic Zone (EEZ) extends 200 nautical miles from its coastline, giving it rights to explore and use marine resources within that zone.
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