I’m sure someone explained this to me in grade school, but I forget the answer. How did we end up with multiple oceans instead of one big “the ocean”?
Are there actual cartographic/nautical lines that say “This is where the Atlantic Ocean ends and the Pacific begins”?
It’s just a human convention, much like “continent”. All the oceans are connected together as one big body of water. We could divide them up differently, if we’d like. If you recall your geology, there was a time when the landmass was one giant continent (Pangea). But since we have these sorta-separate land masses, it sorta make sense to refer to the bodies of water between those land masses as if they were separate entities.
The Ancient Greek word “Ocean” simply meant the waters outside the Med/Black Sea/Red Sea, which they imagined surrounded the entire world. However in their mythology the Okeanos was more of a river than a sea.
Nobody learned until much later that the Atlantic connected to the Indian Ocean, because you’d need to sail around Africa to prove it. And nobody new that the Pacific Ocean existed either.
Columbus was famously named “Admiral of the Ocean Sea”, meaning at that time “Ocean” meant the wild and woolly waters that weren’t part of a particular enclosed sea.
So in that sense we could say that there’s one “Ocean” and it would be improper to speak of Oceans in the plural. But then we notice that the Ocean is more or less divided into particular regions by various continents, and so there’s the Atlantic region of the Ocean, and the Indian region, and the Arctic region, and the Pacific region.
Of course there are no objective physical features that divide the Atlantic from the Pacific, just subjective boundaries, just like there’s no physical feature that divides Europe from Asia.
Well, there is a physical feature that mostly divides the Atlantic from the Pacific: When you’re in Panama, it’s really easy to tell which one is which. The only parts in dispute are the dotted line from the tip of South America to Australia, and similar dotted lines dividing them from the Arctic and Indian Oceans.
I met a guy from South Africa at work a couple of years ago and mentioned that I’d had a dream of standing at the southern tip of Africa, looking out at the ocean. He said that you really could see the Indian and Atlantic Oceans meet. I think he said the two oceans had different currents.
The Southern Ocean is catching on for the band of water around Antarctica. It’s also called the Antarctic Ocean. When I was kid they made sure to tell us there wasn’t an Antarctic Ocean as once suspected to be similar to the Arctic Ocean flowing under an ice cap.
The North and South Atlantic and Pacific Oceans are sometimes considered distinct from their parent oceans as well. And the term World Ocean refers to the four, five, six, or seven oceans that are all connected.
I happen to live on the continent of Rhode Island surrounded by the North West Incomplete Atlantic Ocean.
The movie Endless Summer showed this zone and the great surfing that results from the colliding currents.
Strictly speaking this isn’t true. While the “World Ocean” is one interconnected body of water, if you define oceans in terms of the boundaries of their gyres, there are seven distinct bodies (North and South Atlantic Ocean, North and South Pacific Ocean, Indian Ocean, Arctic Ocean, and Antarctic or Southern Ocean). There is relatively little intermixing between these bodies, each of which have distinct fauna and flora.
There is also a geographical definition of the division between Europe and Asia, that being the Ural and Caucasus Mountains and the intervening bodies of water (Aegean Sea, the Dardanelles, the Black Sea, and the northwestern portion of the Caspian Sea). While Eurasia is one major tectonic plate, that isn’t actually the way we define continents, else we’d have to classify the Arabian Peninsula and India as being seperate continents.
As a practical matter, we define both continents and major bodies of water largely in terms of their navigable features; breaking Eurasia into two continents makes sense in terms of the difficulty in traversing the geographic features separating them; similarly for travelling between the Atlantic and Pacific Oceans, or the trade routes outlining the Mediterranean Sea and Black Sea. This also roughly follows evolutionary and sociological developments, so even if you argue that there isn’t a specific geographic definition of oceans or continents, there is in practice a working definition that is broadly understood and used.
There is a prior thread on exactly this topic:“Only one ocean.”
Stranger
In a physical sense it is just one ocean
South America does not touch antarctica, nor does africa, and there is no landmass in the arctic pole at all so no real hard division.
Its more a way to divide areas up into smaller logical chunks i guess?
You’d literally need a contiguous band of land circling the globe north to south to get
physically separate oceans.
That isn’t to say though that the land as it sits not does not have some unique influences on the “oceans” that do create some localized aspects, temps currents etc
One unique feature that has as yet gone unremarked-upon: The ocean does have a far end where it discharges, and strangely enough, it’s in Delaware.
Technically it is all one big ocean, yes, but for the sake of clarity you need to give it different names for different sections so people know what’s being referred to.
Malaysia Airlines Flight 370 crashed into the Indian Ocean three years ago. Without naming the ocean thusly, it would be very inconvenient - OK, flight MH370 landed in “The Ocean” - where? Near Japan? Near Norway? Near Brazil?
Just like how Europe, Asia, and the Middle East are all linked together as one big landmass, but it’s still better to sub-divide for convenience.
Convenient for Europeans. If any other group were dividing things up, it would almost certainly be divided differently, if it was divided up at all.
Maybe I am totally misremembering but wasn’t the land mass of the Earth at one time all one big huge continent?
Read the first reply in this thread. 
:smack:
The International Hydrographic Organization (IHO) publishes what are often considered to be the “official” boundaries of oceans and seas, though they are in many cases arbitrary and are subject to change from time to time. It so happens that just a few days ago, I was looking at one edition of their document Limits of Oceans and Seas (PDF). I’m not sure if that’s the most up-to-date edition.
Panthalassa is the name geologists have given the ancient ocean that surrounded Pangaea.
Why are there multiple replies? Why not just one big post?
All good points though. Thank you all!
I didn’t realize there were different currents that meet up and reflect, and didn’t realize the oceans had separate flora and fauna. Is that really true? Aren’t there many migratory species that cross vast distances?
That is absolutely fascinating in so many ways:
That thread seems to be, shall we say, lost at sea…
Near the water :smack: