# How many oceans are there on earth? **URL:** \ **Category:** Factual Questions\ **Created:** [January 3, 2013, 3:01am UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914 "2013-01-03T03:01:28Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![TonySinclair](https://avatars.discourse-cdn.com/v4/letter/t/49beb7/32.png) [@TonySinclair](https://boards.straightdope.com/u/TonySinclair)\ **Post date:** [January 3, 2013, 12:32pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/21 "2013-01-03T12:32:55Z")
> [@the\_diego](#): > > Then Eurasia, Africa, the entire Americas (before the canal) and Australia are islands. They might be bounded by several artificially named oceans but so is Greenland, which is smaller than any of the aformentioned but is held to be the biggest. Why do you count the Americas as one, but Eurasia and Africa as two? ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [January 3, 2013, 1:02pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/22 "2013-01-03T13:02:44Z")
> [@DrFidelius](#): > > I just enjoy taking any opportunity to quote Lewis Carroll. I’m that way with Van Morrison: > [@](#): > > You can take all the tea in china > Put it in a big brown bag for me > Sail right around the seven oceans > Drop it straight into the deep blue sea ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [January 3, 2013, 1:15pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/23 "2013-01-03T13:15:24Z")
By Grabthar’s hammer, by the suns of Warvan, I swear that love “Tupelo Honey” as one of my favoritest Van Morrison songs. But there aren’t seven oceans. There are [seven seas](http://en.wikipedia.org/wiki/Seven_Seas), poetic license or no. There is only one ocean. I’m surprised nobody’s said that. ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [January 3, 2013, 1:19pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/24 "2013-01-03T13:19:10Z")
Back on topic: what about the Caspian Sea? If it is not an ocean in its own right, what ocean is it part of? The long gone Paratethys? ---
**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\ **Post date:** [January 3, 2013, 1:52pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/25 "2013-01-03T13:52:41Z")
> [@Exapno\_Mapcase](#): > > There is only one ocean. I’m surprised nobody’s said that. [No more surprising than people skimming through the posts](http://boards.straightdope.com/sdmb/showpost.php?p=15855940&postcount=3). ---
**Author:** ![whc.03grady](https://avatars.discourse-cdn.com/v4/letter/w/a6a055/32.png) [@whc.03grady](https://boards.straightdope.com/u/whc.03grady)\ **Post date:** [January 3, 2013, 1:58pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/26 "2013-01-03T13:58:18Z")
I think the Southern Ocean is sometimes considered a discrete ocean because the Antarctic Circumpolar Current kind of isolates its waters from the other oceans. ---
**Author:** ![Darth\_Panda](https://avatars.discourse-cdn.com/v4/letter/d/ee7513/32.png) [@Darth\_Panda](https://boards.straightdope.com/u/Darth_Panda)\ **Post date:** [January 3, 2013, 2:07pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/27 "2013-01-03T14:07:20Z")
> [@K364](#): > > Yep - Europe is now classified as a Dwarf Continent. Until it gets overrun with orcs… ---
**Author:** ![Michael63129](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@Michael63129](https://boards.straightdope.com/u/Michael63129)\ **Post date:** [January 3, 2013, 2:55pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/28 "2013-01-03T14:55:51Z")
> [@pseudotriton\_ruber\_ruber](#): > > Do the various oceans differ significantly in average temperature, salinity, and other standards of measurement? And is there a serious defense of Europe being a discrete continent (apart from Eurocentricity)? The Arctic and Southern Oceans are of course much colder, being covered with sea ice at least seasonally (Southern Ocean) to completely (Arctic in the winter). Although the Atlantic and Pacific both vary greatly in temperature, so you can’t really use that to define them as separate oceans, unless perhaps you use the areas that stay ice-free year-round. [Salinity](http://www.earthtimes.org/scitech/nasa-aquarius-satellite-maps-salinity-oceans/1407/) also varies greatly even within ocean basins, with the Atlantic being noticeably saltier. As far as dividing the oceans into separate areas goes, it is easy to see the Pacific, Atlantic, Indian and Arctic as separate oceans since they are all divided to some extent by landmasses (some also divide the Atlantic and Pacific into north/south although it is kind of hard to see that in the Pacific, but like using currents to define the Southern Ocean, [ocean currents](http://www.google.com/imgres?imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/0/06/Corrientes-oceanicas.gif/640px-Corrientes-oceanicas.gif&imgrefurl=http://en.wikipedia.org/wiki/Ocean_current&h=334&w=640&sz=55&tbnid=12YPEPHabU1F4M:&tbnh=63&tbnw=120&zoom=1&usg=__VxaR9nCJgkFPxq9avnqNKW80EIg=&docid=INrRm7JSTuwM_M&sa=X&ei=g5vlUNGKKaSw2wXJi4GoCg&ved=0CEAQ9QEwAQ&dur=3589) are different on opposite sides of the equator). ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [January 3, 2013, 2:57pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/29 "2013-01-03T14:57:45Z")
only one; Blue. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [January 3, 2013, 3:07pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/30 "2013-01-03T15:07:51Z")
> [@TokyoBayer](#): > > [No more surprising than people skimming through the posts](http://boards.straightdope.com/sdmb/showpost.php?p=15855940&postcount=3). [Whoosh.](https://www.google.com/search?num=100&hl=en&newwindow=1&tbo=d&site=webhp&q=site%3Astraightdope.com+%22I%27m+surprised+that+nobody%22&oq=site%3Astraightdope.com+%22I%27m+surprised+that+nobody%22&gs_l=serp.3...4650.4650.0.5510.1.1.0.0.0.0.68.68.1.1.0.les%3B..0.0...1c.1.4rOIyy2sIvI) ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [January 3, 2013, 7:25pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/31 "2013-01-03T19:25:31Z")
I would still urge you to reconsider the status of the Caspian. It is: A) salty; B) of a somewhat notable size; and: C) though it once was connected to the Main Ocean; D) it is now isolated. This is, (in my mind at least) enough to render it the status of “ocean”. So that leaves us with a number of 2 oceans: The Main Ocean (incorporating the Atlantic, the Pacific, etc.) and the Caspian Sea. Anyone have a third? ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [January 3, 2013, 7:37pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/32 "2013-01-03T19:37:05Z")
I would still urge you to reconsider the status of the Caspian. It is: A) salty; B) of a somewhat notable size; and: C) though it once was connected to the Main Ocean; D) it is now isolated. This is, (in my mind at least) enough to render it the status of “ocean”. So that leaves us with a number of 2 oceans: The Main Ocean (incorporating the Atlantic, the Pacific, etc.) and the Caspian Sea. Anyone have a third? ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [January 3, 2013, 7:44pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/33 "2013-01-03T19:44:09Z")
> [@Ignotus](#): > > I would still urge you to reconsider the status of the Caspian. It is: > A) salty; > B) of a somewhat notable size; > and: > C) though it once was connected to the Main Ocean; > D) it is now isolated. > > This is, (in my mind at least) enough to render it the status of “ocean”. So that leaves us with a number of 2 oceans: The Main Ocean (incorporating the Atlantic, the Pacific, etc.) and the Caspian Sea. > Anyone have a third? Oh yeah? What about the Great Salt Ocean in Utah? ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [January 3, 2013, 7:55pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/34 "2013-01-03T19:55:36Z")
Was it ever connected to the Pacific? In that case, it might count. ---
**Author:** ![yabob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yabob/32/2821_2.png) [@yabob](https://boards.straightdope.com/u/yabob)\ **Post date:** [January 3, 2013, 8:11pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/35 "2013-01-03T20:11:56Z")
> [@Ignotus](#): > > I would still urge you to reconsider the status of the Caspian. It is: > A) salty; > B) of a somewhat notable size; > and: > C) though it once was connected to the Main Ocean; > D) it is now isolated. > > This is, (in my mind at least) enough to render it the status of “ocean”. So that leaves us with a number of 2 oceans: The Main Ocean (incorporating the Atlantic, the Pacific, etc.) and the Caspian Sea. > Anyone have a third? It was ONCE connected to the main ocean … to my mind, that’s an argument to downgrade it from “ocean” to “sea” if it actually was one. Wiki notes: > [@](#): > > The word “sea” is often used interchangeably with “ocean”, but strictly speaking a sea is a body of saline water (possibly a division of the World Ocean) partly or fully enclosed by land. Note that it says “possibly” a part of the World Ocean, BTW. There’s no requirement that a “sea” be part of an ocean. Landlocked seas: > **[Sea](https://en.wikipedia.org/wiki/Sea#Landlocked_seas)** > > A sea is a large body of salt water. There are particular seas and the sea. The sea commonly refers to the ocean, the interconnected body of seawaters that spans most of Earth. Particular seas are either marginal seas, second-order sections of the oceanic sea (e.g. the Mediterranean Sea), or certain large, nearly landlocked bodies of water. > The salinity of water bodies varies widely, being lower near the surface and the mouths of large rivers and higher in the depths of the ocean; however, the... What we also need is a definition for the dividing line between a “sea” (inland variety) and a “salt lake”. The “Great Salt LAKE” is a heck of a lot larger than the “Dead SEA”, never mind the “Salton SEA”. ---
**Author:** ![drastic\_quench](https://avatars.discourse-cdn.com/v4/letter/d/e36b37/32.png) [@drastic\_quench](https://boards.straightdope.com/u/drastic_quench)\ **Post date:** [January 3, 2013, 8:19pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/36 "2013-01-03T20:19:16Z")
> **[Panthalassa](https://en.wikipedia.org/wiki/Panthalassa)** > > Panthalassa, also known as the Panthalassic Ocean or Panthalassan Ocean (from Greek πᾶν "all" and θάλασσα "sea"), was the superocean that surrounded the supercontinent Pangaea, the latest in a series of supercontinents in the history of Earth. During the Paleozoic–Mesozoic transition c. 250 Ma it occupied almost 70% of Earth's surface. Its ocean floor has completely disappeared because of the continuous subduction along the continental margins on its circumference. Panthalassa is also refer The s... ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [January 3, 2013, 10:44pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/37 "2013-01-03T22:44:28Z")
Yeah, and the Caspian Sea can swallow them both… without any remarcable change of the shoreline… ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [January 3, 2013, 11:42pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/38 "2013-01-03T23:42:20Z")
I’m sorry… lost myself somewhere down there… won’t happen again … appollo- logies -to you everyone! (GLUG…GLUG…GLUG…(wipes my mouth) … and now, when everything is hopefully settled: does any one of you have a quick xor dirty definition of what constitutes an ocean, and what’s merely a sea? ---
**Author:** ![the\_diego](https://avatars.discourse-cdn.com/v4/letter/t/7bcc69/32.png) [@the\_diego](https://boards.straightdope.com/u/the_diego)\ **Post date:** [January 3, 2013, 11:50pm UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/39 "2013-01-03T23:50:23Z")
An ocean has for its bottom the ocean floor, which is the basaltic crust. The Caspian and Black might not qualify, not even the Med since the Med is just a depression on the boundaries of the two colliding plates that are North Africa and Southern Europe. All three still have continental granite at their bottoms. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [January 4, 2013, 12:11am UTC](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914/40 "2013-01-04T00:11:27Z")
> [@Michael63129](#): > > As far as dividing the oceans into separate areas goes, it is easy to see the Pacific, Atlantic, Indian and Arctic as separate oceans since they are all divided to some extent by landmasses (some also divide the Atlantic and Pacific into north/south although it is kind of hard to see that in the Pacific, but like using currents to define the Southern Ocean, [ocean currents](http://www.google.com/imgres?imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/0/06/Corrientes-oceanicas.gif/640px-Corrientes-oceanicas.gif&imgrefurl=http://en.wikipedia.org/wiki/Ocean_current&h=334&w=640&sz=55&tbnid=12YPEPHabU1F4M:&tbnh=63&tbnw=120&zoom=1&usg=__VxaR9nCJgkFPxq9avnqNKW80EIg=&docid=INrRm7JSTuwM_M&sa=X&ei=g5vlUNGKKaSw2wXJi4GoCg&ved=0CEAQ9QEwAQ&dur=3589) are different on opposite sides of the equator). Good point. So, [eight](http://en.wikipedia.org/wiki/File:Corrientes-oceanicas.gif) then. [Previous page](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914.md?page=1) [Next page](https://boards.straightdope.com/t/how-many-oceans-are-there-on-earth/645914.md?page=3)