While we’ve given our planet’s oceans separate names, in reality there’s no border between them, and currents continually flow between them and mix their waters. The Atlantic and Pacific oceans ‘meet’ at the southernmost tip of South America. In this region, a strong current carries water from west to east, sweeping water from the Pacific into the Atlantic.
The videos you may have seen online showing two different coloured bodies of water drifting alongside each other are actually showing light-coloured, sediment-rich freshwater from melted glaciers meeting dark, salty ocean water in the Gulf of Alaska (and over time, currents and eddies cause these to mix, too).
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