Why is the ocean salty?
Why is the ocean salty?
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** Why is the Ocean Salty? **
Satellite view of La Plata River discharge to the Atlantic Ocean. (Credit:
Satellite view of La Plata River discharge to the Atlantic Ocean. One way
minerals and salts are deposited into the oceans is from outflow from
rivers, which drain the landscape, thus causing the oceans to be salty.
View the picture full size. View full size
You may know that the oceans cover about 70 percent of the Earth's surface,
and that about 97 percent of all water on and in the Earth is
saline—there's a lot of salty water on our planet. By some estimates, if
the salt in the ocean could be removed and spread evenly over the Earth's
land surface it would form a layer more than 500 feet (166 meters) thick,
about the height of a 40-story office building (NOAA). But, where did all
this salt come from? If you get into folk stories and mythology you will
see that almost every culture has a story explaining how the oceans became
salty. The answer is really very simple. Salt in the ocean comes from rocks
on land. Here's how it works:
*From precipitation to the land to the rivers to the sea*
The rain that falls on the land contains some dissolved carbon dioxide from
the surrounding air. This causes the rainwater to be slightly acidic due to
Why Is the Ocean Salty?
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** Why Is the Ocean Salty? **
By Anne Marie Helmenstine, Ph.D., About.com Guide
"The ocean contains a lot of sodium and chloride, which make salt."
The ocean is salty compared with most lakes in part because the oceans have
had a very long time to react with minerals.
*Question: *Why Is the Ocean Salty?
Have you ever wondered why the ocean is salty? Have you wondered why lakes
might not be salty? Here's a look at what makes the ocean salty and why
other bodies of water have a different chemical composition.
*Answer: *It's really easy to understand why the ocean is salty. The oceans
have been around a very long time, so some of the salts were added to the
water at a time when gases and lava were spewing from increased volcanic
activity. The carbon dioxide dissolved in water from the atmosphere forms
weak carbonic acid which dissolves minerals. When these minerals dissolve,
they form ions, which make the water salty. While water evaporates from the
ocean, the salt gets left behind. Also, rivers drain into the oceans,
bringing in additional ions from rock that was eroded by rainwater and
The saltiness of the ocean, or its salinity, is fairly stable at about 35
parts per thousand. To give you a sense of how much salt that is, it is
estimated that if you took all the salt out of the ocean and spread it over
the land, the salt would form a layer more than 500 feet (166 m) deep! You
might think the ocean
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