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    Hi there! I've stumbled this awesome picture, without a clue of what it is:
    http://www.mediafire.com/view/?86kyg3liclgr103
    Would you pls tell me what is this phenomenon called? What's the explanation behind it? Where & when can we see it happens?
    Tks in advance
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    It's turbulance created by the mixing of waters of different densities - where an estuary meets the ocean etc.

    Having had a google to see if there was a technical term for it, your picture was the first to come up from a site attempting to promote Islam - i hope we can stick to proper science rather than having that religious waffle thrown down are throats on a site for geography and earth sciences academic help.
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    (Original post by 12tn2)
    Hi there! I've stumbled this awesome picture, without a clue of what it is:
    http://www.mediafire.com/view/?86kyg3liclgr103
    Would you pls tell me what is this phenomenon called? What's the explanation behind it? Where & when can we see it happens?
    Tks in advance
    Not sure it has a name, but it is caused by the difference in water, i.e. in an estuary where the river mouth meets the ocean/sea. One of the most famous sites of this is the Amazon River, where the estuarine water full of mud/sediment meets the salty ocean water of the Atlantic. It's caused by both the salinity of the water and if the water contains a lot of sediment/or it doesn't. Below is a picture of the Amazon meeting the Atlantic.

    http://www.igougo.com/photos/journal...b9_prefRes.jpg

    -AS level Geologist & Geographer and general lover of the natural world-
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    Tks guys, so it doesn't have a scientific name... But now given those waters enough time they will merge, won't they? I think the reason the barrier exists is that more & more water of both sources are coming toward it & keep it up (bah, sorry for my bad English, it's kinda hard to express). IMO, the differences in salinity & sediment actually encourage the merging of the two waters.
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    * bump *
    is this a matter of physics, not geography? Or something else?
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    Freshwater mixing with saltwater happens in coastal regions around the world, because, of course, rivers contain freshwater. The interface is usually maintained either near the coast or beneath the land surface, along what's called the 'zone of dispersion'. It's usually a fairly gradual transition zone, and it's not all that common to see a very visible difference in density (except where there are highly sedimented esturine outflows). In your picture we see something different: a very clear and sudden transition, no visible sediment, and ostensibly no coast in sight.

    Therefore, the phenomenon in your picture is almost certainly caused by the meeting of saline ocean with a large body of glacial meltwater. The colour difference is generally indicative of density: the darker area is denser (i.e. more mass per unit volume) saltwater, and the lighter area the glacial melt. As already mentioned in the thread, liquids of markedly different densities generally resist mixing.

    Will they mix eventually? As with estuaries, the nature and extent of mixing depends on factors such as currents, winds and tides, but if this is a closed system, yes, they will eventually mix. As you suggest, if you continue to add freshwater input, the process may be slowed. The process is also complicated if the bodies are at different temperatures, but we'll not get into that XD

    If you looked at a profile image, you'd probably find that beneath the surface there is a degree of stratification: the line doesn't cut straight down. We thus also get something called 'vertical mixing' (which in some areas is a vital process in oceanic nutrient cycling).

    Because saltwater is a solution (salt molecules suspended in water), the mixing happens by diffusion, a physical process defined by Fick's laws. So, depending on how you want to look at it, it's a matter of physics and physical chemistry and geography!
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    (Original post by uthred50)
    SNIP
    or simply put coastal geography.
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    (Original post by clareramos)
    or simply put coastal geography.
    Actually, as I explained, I'm fairly certain it's not coastal. It's probably taken somewhere out to sea in the North Atlantic.
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    (Original post by uthred50)
    Actually, as I explained, I'm fairly certain it's not coastal. It's probably taken somewhere out to sea in the North Atlantic.
    it will be to do with coastal geography as will happen in certain areas due to way the coast is formed, oceanography or hydrology/hydrography, so going even broader physical geography.

    There is one in Berwick-Upon-Tweed that is very visible and is very close as in metres to mouth of the Tweed. look on google maps you are able to sort of see it and how close it is.
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    (Original post by clareramos)
    it will be to do with coastal geography as will happen in certain areas due to way the coast is formed, oceanography or hydrology/hydrography, so going even broader physical geography.

    There is one in Berwick-Upon-Tweed that is very visible and is very close as in metres to mouth of the Tweed. look on google maps you are able to sort of see it and how close it is.
    Again, in this case I suspect it's caused by glaciers melting rather than coastal phenomena, although it has similar effects to what happens in estuaries
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    (Original post by uthred50)
    Again, in this case I suspect it's caused by glaciers melting rather than coastal phenomena, although it has similar effects to what happens in estuaries
    in general they are all linked to coastal geography/oceangraphy and hydrology/hydrography in some way shape or form. less glaciation. could see it having links to geomorphology
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    As already mentioned in the thread, liquids of markedly different densities generally resist mixing.
    Actually it's had not been mentioned iirc Would you pls point me to some sites talking about that fact: highly different densities resist mixing? Tks.
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    (Original post by 12tn2)
    Actually it's had not been mentioned iirc Would you pls point me to some sites talking about that fact: highly different densities resist mixing? Tks.
    google it?
 
 
 
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