The video owner has disabled playback on external websites.
This video is no longer available on YouTube.
This video cannot be played right now.
Watch on YouTube
ابزارهای یادگیری هوش مصنوعی را باز کنید
ثبتنام کنید تا به ابزارهای قدرتمندی دسترسی پیدا کنید که به شما کمک میکنند سریعتر از هر ویدیو یاد بگیرید.
There’s Fresh Water Under the Ocean. Can You Drink It?
زیرنویسها (214 بخشها)
More than 2000 years ago,
a Roman geographer told a strange tale
about the Mediterranean Sea.
The locals would hop on a boat,
travel to a specific spot four kilometers off the coast of Syria,
and collect seawater with a funnel connected to a long tube.
Then, they would drink it.
Amazingly, this water was fresh.
Two millennia and one Talking Heads song later,
we know this story isn’t complete malarky.
Scientists have discovered fresh water under the ocean in locations around the globe.
But how much is there?
And more importantly, can we access it?
[SciShow Intro]
Like many discoveries throughout history, modern scientists stumbled across fresh
undersea groundwater by happenstance. In the 1970s,
expeditions off the coasts of Massachusetts and New Jersey
were collecting sediment samples from beneath the seafloor.
At the time, the prevailing assumption
was that salty ocean water would completely penetrate the sediment
beneath the seafloor.
But in the samples they pulled up, the water was fresh.
Somewhere, that Roman geographer’s skeleton must have shouted,
“Vindicatio- wait what the heck is an old Jersey?”
But let’s back up and cover some basics.
The saltiness of water is often measured in units of parts per thousand.
Basically, it compares the weight of dissolved salts…
like sodium, chloride, magnesium, and sulfate…to the weight of water in a given volume.
Seawater typically has a saltiness of about 35 parts per thousand.
Which our props people have approximated
by dissolving 35 grams of table salt in a liter of water,
and handing me a sample to taste test.
“OK, don’t try this at home.”
The water found by those expeditions in the 1970s
was a lot fresher than seawater, less than 3 parts per thousand.
Which I have also been asked to taste test.
Still not great I'm gonna be honest,
but not as bad as the first one.
Tastes a little like soup
Now, 3 parts per thousand is technically on the lower end of what’s called brackish water.
While it’s ten times fresher than the rest of the ocean,
it’s not quite fresh enough to drink comfortably.
The US Geological Survey, or USGS,
زیرنویس کامل در پخشکننده ویدیو موجود است
با تمرینها یاد بگیرید
تمرینهای واژگان، گرامر و درک مطلب از این ویدیو بسازید
نظرات (0)
برای نظر دادن وارد شویدثبتنام کن و همه امکانات رو باز کن
پیشرفتت رو دنبال کن، واژگان رو ذخیره کن و تمرین کن
حالت تعاملی
آزمون
پاسخ صحیح:
ویدیوهای مرتبط
What The Media Got Wrong About Octopus Cities
How A Nuclear War Will Start - Minute by Minute
The Genius Spiders Changing How We Think About Brains
The Biggest Eruptions That Changed Earth Forever
The Lazy Loading Pattern: How to Make Python Programs Feel Instant
SciShow
آزمون
پاسخ صحیح:
آزمونها هنگام تماشای ویدیو ظاهر میشوند
راهنمای حفظ
از این ویدیو
شروع رایگان یادگیری زبان
