Imagine Earth with an even 50/50 split
between continents and oceans.
Our planet covered half by land
and half by water.
When it comes to making life
possible on a planet,
water is an absolute must-have.
That's why we look for alien life
on worlds where liquid water could exist.
When it comes to our own planet,
71% of its surface is covered by water.
Most of that is in our five oceans.
Together, they form one global ocean.
Now, if you replaced nearly
a quarter of our ocean water with land,
how soon would Earth turn into
just another lifeless rock in space?
Thanks to global warming,
Earth’s sea levels are currently rising.
But if you wanted to balance
the planet’s land-to-water ratio,
you’d see the sea levels
absolutely plummet.
And not just a few meters,
but around 3 km (1.9 mi).
Earth would look very different.
The regions around
both the North and South poles
would be completely dried out.
And every continent on the planet
would expand.
And not just a little, either.
All this newly emerged
territory around the world
would be roughly equal
to the current surface areas of
Asia, Europe, Africa
and North America combined.
That would be an enormous
amount of unused space.
Everything extending off the old coasts
would be relatively flat.
But some of the areas
that used to be deep ocean
would reveal vast corridors
and steep crevasses.
As you explored this new land,
you’d discover that the one global ocean
would be no more.
All of the oceans
would be separated from each other.
And all of the continents
would be one connected landmass.
And this would be good news
for evolution.
Early humans
didn't have any ships or planes.
We spread across the globe
simply by walking.
Venturing away from Africa
some 70,000 to 100,000 years ago,
we found our way to Europe and Asia.
Eventually, we were able to cross
a land bridge connecting
Asia to the Americas,
possibly as far back as 20,000 years ago.
With the 50/50 split in place,
you’d now be able to cover
even more ground.
Finally, you could take that
around-the-world trip
you’ve always dreamed of.
All on your own two feet.
But this shifting balance of water and land
wouldn’t be all fun and games.
With so much less water
covering the surface,
our ocean currents would be disrupted.
And this would seriously
destabilize the climate.
Currents distribute
the heat that’s absorbed by the oceans
around the globe.
Disrupting them would mean
even colder temperatures
around the North and South poles.
While the already hot equatorial regions
would get even hotter.
Climate change would speed up too.
All because oceans
wouldn't be able to absorb
so much carbon dioxide from the air.
That excess carbon dioxide
would blanket the planet
and raise temperatures.
Rain levels would also drop off.
And this would create
dangerous droughts,
as well as new deserts
in many inland areas.
So while there may be an abundance
of new land available,
large stretches of Earth
could become uninhabitable.
Plants, animals
and humans would all need to adapt
to being less dependent on water.
Or at least start using it more efficiently.
Water scarcity could result
in animals evolving to be smaller,
with more making the jump
to a strictly carnivorous diet.
And sadly, the abundance of life
that today's oceans support
would struggle to survive.
And maybe the most
surprising consequence
that you’d need to get used to is that
your pee would likely change forever.
Usually, urine is made up
of more than 90% water.
But with less water in your daily life,
yours would become much darker
and start to smell like ammonia.
I mean, things could be worse.
You could drain the oceans
of every drop of water they have.
But that’s a story for another WHAT IF.