
When we look at our planet from space
one color dominates that's why Earth is
called the Blue Planet about three
quarters of our world is covered with
water but there's a catch
96.5 percent of this water is trapped in
the oceans and if you remember the first
time your parents took you to the
seaside drinking that water is a big
No-No so why is ocean water salty and
undrinkable
there are two main reasons the first is
run off water from the land rain water
is slightly acidic its pH factor is
somewhere between five and five and a
half for comparison pure water has a pH
factor of seven and the acid we find in
batteries is a bit more than zero such
rain erodes rocks when it falls on the
ground this releases ions such as sodium
and chloride they end up in rivers and
streams that eventually empty into the
ocean living organisms remove some of
the good ions but the rest remains over
time this increases their concentration
in the water
oceans have their own salt Powerhouse
vents in the sea floor let out a
hydrothermal fluid sounds complicated
but it's easy to understand water seeps
down the gaps on the ocean floor then
the magma from the Earth's core heats up
the water there is a chemical reaction
that frees seawater from oxygen it picks
up Metals such as iron and zinc the
vents on the sea floor release this
metallic water back into the ocean
during an underwater volcanic eruption
the process speeds up salt and other
minerals are directly released into
Earth's oceans over time Salt
accumulates on the sea floor and forms
domes these deposits occur under dry
land as well
some places on the globe have a large
number of salt domes the Gulf of Mexico
is just one example beneath the waves
they affect the salinity of water other
factors that determine how salty a body
of water is include evaporation air
temperature and precipitation
the general rule is that salinity is low
near the equator and at the poles all
the oceans and seas in between are
likely to have high salinity
scientists estimate that dissolved salts
make up three and a half percent of the
weight of the world's seawater
the waters that empty into the ocean
such as lakes and rivers are fresh water
so why is the sea water salty to answer
this question we must travel into our
planet's past
researchers believe that primeval Seas
weren't as salty as they are today but
over time rainfall washed away the rocks
on land transporting vast amounts of
salt into the oceans the process has
been going on for more than 3.8 billion
years today some 4 billion tons of
dissolved salts end up in Earth's oceans
every year the input and output of salt
are fairly balanced this means that
seawater's salinity is stable
so why can't we drink seawater we
already take salt into our bodies with
food and drinks it is called dietary
salt the World Health Organization
recommends that humans consume no more
than a teaspoon per person per day you
shouldn't go over that amount if you
want to keep your heart healthy
centuries ago salted beef and pork were
the standard diet of seafarers meat was
preserved using salt at Sea fresh fruit
and vegetables would go bad after just a
couple of weeks before Refrigeration
this was the only way to keep fresh
pickling was another option for storing
food
the reason why we can't drink seawater
is the salt content the percentage of
this mineral in our blood is nearly four
times lower than the percentage of salt
in seawater our bodies simply cannot
process such a high amount of the
substance when we intake salt as part of
our diet we also drink liquids when you
serve pretzels you probably have a glass
of water or juice nearby it helps quench
The Thirst and keep the salt levels in
check if we drink water straight from
the ocean the exact opposite happens we
just become thirstier
our body absorbs both water and salt
they end up in our bloodstream the
organs responsible for getting all this
salt out of our blood are the kidneys
but they need water to perform their
Duty
the higher the salt content the more
water they need to wash it away when the
process repeats itself several times
over you become dehydrated
this is the process of losing water from
the body and there's another catch you
start releasing more water than you take
in when you drink seawater the
difference leaves you thirstier than you
were when you started drinking seawater
not a good idea to begin with
but submarine mammals such as whales
seals and even seagulls can drink water
from the sea just like we drink tap
water
kidneys of these mammals are super
efficient birds have special glands in
their beaks that prevent salt from
getting inside their bloodstream
scientists found that the only land
animal that can drink sea water is the
camel and if you ever wondered if fish
drank sea water they do
the gills and kidneys help them pump out
the excess salt
for humans to drink ocean water it first
needs to go through desalinization this
is the process of removing salt from
seawater and there's a lot of it to take
away
estimates show that if we laid out all
the sea salt across Earth's land mass it
would be higher than the Statue of
Liberty that's why desalinization on a
global scale isn't realistic right now
less than half a percent of the drinking
water we produce comes from seawater and
the demand for potable water is only
going to increase the current rate of
consumption means that the demand for
fresh water doubles every 20 years
the biggest issue with desalinization is
the energy cost it takes 10 times more
energy than other Water Production
methods and the carbon footprint is huge
large desalinization plants often need
to have their own power stations this is
all because of the technology behind the
process salt dissolves easily in water
it creates a strong chemical bond with
water that is hard to break
desalinization facilities mostly use
reverse osmosis to achieve this large
pumps exert pressure on seawater to push
it through a filter its membrane is so
fine that each pore is a fraction of the
size of a human hair the filter allows
for water molecules to pass larger salt
molecules remain Trapped In The Membrane
for every quarter of a gallon of fresh
water the plant generates through
desalinization there is the same amount
of water that is now twice as salty
hardly the ideal method of water
purification
the idea that humans could drink sea
water isn't new in the mid 4th Century
BCE the famous Greek philosopher
Aristotle considered using a series of
filters to remove salt from water ships
in the 16th century had small portable
distilleries that could boil sea water
this was merely Patchwork since exposing
seawater to high temperatures doesn't
make it drinkable such thermal
processing only sterilizes the water you
would need to catch the steam that
evaporates and wait for it to cool down
before it's safe to drink this is a
complex and time-consuming method that
is probably not worth the effort
let us imagine for a second that we got
rid of all the salt from the Earth's
oceans we would get an endless supply of
drinking water but at what cost there
are millions of animal and plant species
that are adapted to salt water these
include Plankton the basis of all marine
life they wouldn't have enough time to
adapt to the new conditions not all fish
are like the salmon which thrives both
in fresh and salt water
the sudden switch would also have a
profound effect on our planet since
fresh water is less dense it would
immediately cause the ice cap in the
Arctic to sink by four inches this would
trigger the largest tidal wave the
planet has ever seen although the idea
of desalinization on a global scale
sounds good on paper we should take it
with a grain of salt.


Comments (1)
Very interesting! Fantastic!