3.8 billion gallons – that’s how much water people drink around the world every
day. It might sound like an entire ocean, but it only counts for about ½ of 1% of the
water on Earth… And we’re running low! So what if, we had entire oceans of fresh
water instead of the undrinkable salty kind?
At first glance, it seems like a fairy tale. You see, people live on land that’s surrounded
by ginormous puddles of H2O and Sodium Chloride that’s pretty much useless to us, if we’re
talking about drinking and consuming the stuff, that is. (By the way, those are the chemical
compound names for water and salt, if you’re hoping to earn some extra credit here.) Lots
of people on certain parts of continents don’t have access to fresh water from rivers or
lakes, and this crisis is getting more and more serious each year. Every 7th person on
the planet suffers from a lack of access to clean drinkable water right now. And some
experts say that as the world population doubles by 2030, that statistic will skyrocket to
one-half!
So, wouldn’t it solve the problem if we had an unlimited ocean of fresh water? The
short answer is, nope.
But first, it’s important to understand why our oceans are briny to begin with. It
seems so disappointing that we have all this water around us, yet we can’t drink it,
so people go without. Well, let me break it down for you…
Rivers constantly bring fresh water to the oceans. You’d think these sources would
dilute the sea and decrease the salt content. But in fact, it’s quite the opposite. Water
in rivers is also brackish – it’s just 70 times less salty than in the ocean. On
its way to the sea, rivers wash out salt from rocks and carry it with them. Once the water
reaches its destination, that salt remains in the ocean, but the extra water doesn’t
dilute the overall salt content because it evaporates. This is the same reason why rivers
aren’t that salty. They carry and dump it all into the sea!
Each year 4 billion tons of salt are carried into the ocean just from rivers alone. If
you keep doing that for the billions of years this planet has been in existence, you can
imagine how much salt would gather there. Hey, you don’t even need to imagine, I’ll
tell you right now: 50 quadrillion tons -- that’s 50 followed by 15 zeros! (Go ahead, write
it out. I’ll wait here for you. Um, no I won’t.) That’s how much salt is in our
world’s oceans. If you take away all the water, you’d be left with a layer of salt
almost 500 feet thick! Now, just imagine a Margarita glass big enough to use that.
Ok, so rivers have been adding salt to the ocean for years and years, and years and years
and years. Does that mean seawater was originally fresh? Eh, maybe. The problem with that theory
is the fact that the salt composition in rivers and oceans is different. Sea salt derives
from a hydrochloric acid, while river salts are from carbonic acid. More scientists today
believe that the oceans have been salty from the start because of volcanic activity. To
really simplify a highly complex process: the stuff that these early volcanic eruptions
produced would pour to the Earth in the form of acid rain and react with the rocks that
would later become the seabed. The result of that reaction was a brackish solution,
aka: salt!
Ok, now that you know 97% of all the water on the planet has always been briny, you can
safely assume that it’s this way for a reason. …And magically pushing a button to make
it fresh water in this hypothetical situation would be devastating for life on this planet.
The most obvious consequence is that the innumerable forms of marine life can only exist in briny
water – they wouldn’t survive in fresh water. Now, we only know about a little over
200,000 species of oceanic life, but that’s just a drop in the bucket - albeit a very,
very big bucket. There could be millions more! So, what would that mean for us humans? Well,
without them, we’d lose this source of food, which would have a serious impact on not only
the countries that are highly dependent on their fishery sectors, but also those they
export to!
You also must consider the 10,000 known species of underwater algae. Algae are unique as they’re
both plants and animals. Like animals, algae are capable of feeding on organic material
in their environment. Like plants, they take part in photosynthesis. They play a huge role
in sustaining life because of this. Just imagine how severe the drop in oxygen and the spike
in carbon dioxide levels will be without all this salt-water-loving algae. This means the
Greenhouse Effect will intensify, and we’re already having enough problems with that as
it is! In short, the global ecosystem would collapse as all the existing food chains would
be destroyed.
Oh, but it doesn’t stop there! The oceans play a critical role in shaping the climate.
More specifically, it’s ocean currents that can really affect the weather even on land!
Ocean currents exist mainly because of density differences. Remember, as surface water evaporates
under the hot sun, the salt gets left behind. This saltier water is denser and sinks, causing
it to be cooler than the less dense water on the surface. This movement of water while
sinking and rising is one major thing that causes ocean currents. (Of course, other things
like wind and landforms play their part too, but that’s a whole other video itself! If
you’d be interested in seeing something like that, let me know down in the comments!)
Anyway, these currents influence the climate by transporting heat. They can carry warmed
or cooled water as far as several thousand miles. The displaced water can then warm or
cool the air and the land over which this air blows. The Gulf Stream brings warm water
from the tropical and subtropical Atlantic northward and bathes the shores of Western
Europe. As a result, the climate there is much warmer than it could be in other parts
at that latitude. Thus, Glasgow’s climate is a lot milder than, say, Moscow, Russia
even though they’re both at the same latitude on the globe!
So, yeah, ocean currents make the climate on earth a lot more tolerable and suitable
for living. Take salt from the oceans, and the currents will disappear. And I guess Western
Europeans would be donning furry Russian hats!
Salt water has a much lower freezing temperature too. Without the salt, bigger parts of the
oceans would turn to ice during the winter. Hot climatic zones would get hotter, cold
ones – colder. Bigger storms would happen more frequently both on land and in the ocean.
The climate changes would be so drastic that life on Earth for the existing species becomes
impossible.
Plus, all that salt would eventually start appearing right back in the oceans! Minerals
from the Earth’s crust would start dissolving into the sea again, and oceanic floor vents
would also pump minerals into the water. So perhaps it’s best if we just leave all the
NaCL in the H2O and look to bright scientific and innovative minds to think up ways to solve
the world’s freshwater crisis. And, of course, we can all do our part by being a little more
careful about our consumption. Come on, you don’t need that hour-long shower no matter
how relaxing it might be!
Hey, you’re a bright mind! Do you know any ways to get more fresh water? Share your ideas
down in the comments! If you learned something new from the video, then give it a like, share
it with a friend, and here are some more cool videos to check out from the Bright Side of
life!