But one place still remains a mostly uncharted mystery; our oceans.

Oceans cover about 70% of Earth's surface, but we know more about the geography of Mars

than we do about what lies on the bottom of the sea.

But all that might change.

Around the world people are looking to finally reveal the secrets of our deep oceans for

both scientific and economic gains.

So, how close are we to completely mapping the ocean?

For thousands of years people have taken to the seas with the goal of finding out just

how deep our oceans are.

This mainly consisted of tying a weight to a long rope and throwing it over the side

of a boat.

This is actually how we discovered the deepest part of the ocean,

Mariana Trench.

Since then we've obviously advanced with our technology, and have actually already

used satellites to map the entire ocean.

Kind of.

The way that they do satellite mapping of the ocean, they use altimetry.

As the satellite is passing over an orbit, if there's a higher concentration of rock,

or sea mounts, or anything that's beneath the ocean surface, the increased gravity actually

causes some of the water to collect around the top of it and they

can measure the different heights of the ocean surface.

Using certain algorithms and processing that data, they can actually get a decent representation

of what it's like down there.

But decent isn't good enough.

Satellite mapping only gives us about a 5km resolution of the ocean floor, meaning we

can see features and objects larger than 5km across.

To put that in context, most of Mars has been mapped to 6m and almost all of Venus and 100%

of the moon has been mapped to 100m.

Less than 10% of our oceans, and maybe closer to 5%, have been mapped to this detail.

that really is disappointing for a marine biologist, really disappointing for anyone

who's thinking about doing business on the oceans, managing the oceans, thinking about

how to get what we need from the future of the oceans...We're sort of fumbling around

in the dark…

Having a detailed map would greatly change how we use the ocean.

It would help with safety, like charting potential hazards that could take down a ship.

It could lead to more accurate climate models, better understand tsunami dangers and improved

weather predictions.

It would help with laying down ocean cables, fiber optics and pipes.

However, it could also help advance the exploitation of the ocean's natural resources, like those

precious metals used to create your cell phone.

But having a detailed map will help us better understand how to protect the ocean when the

inevitable rush to further exploit it begins.

The International Seabed Authority, which is in charge of overseeing seabed mining on

the high seas, part of its charge is to set up some areas of special biological interest

that will not be mined and putting them in the right places, in places that matter for

biodiversity and matter for ocean function, requires knowing what's down there...so you

don't mine, for example, a rainforest and put your protected area in a desert, right?

So ocean mapping may be this double edged sword.

On one side, people are trying to map the ocean to help understand and protect it, making

geological and biological discoveries along the way.

Others are trying understand and exploit it, potentially harming the ocean floor as they

go.

But these two factions might work together to achieve a goal that could see both sides

benefiting.

How do you manage what you don't understand

We can map out things like manganese nodules,

that have the potential for copper and nickel and cobalt.

We depend on ocean mapping for before any kind of oil explorations done

they must map the seafloor

both the surface and the subsurface of the seafloor,

and in this case, here we're going to get a full understanding

through mapping what's there

and then can set up the appropriate management approaches

So if everyone wants this map, why hasn't it been done yet?

Well, it'll cost a lot of money.

and take a lot of time.

Maybe as much as 200 ship years.

So with the current day technology, it would take about 200 years for one ship to map the

whole ocean or 200 ships one year.

The question is the cost.

We've estimated that to map the entire ocean at a reasonable level of resolution would

cost on the order of three billion dollars and you'd say, "Wow, gee, who would ever spend

three billion dollars to map a planet?"

And I point to the fact that we've sent missions to the moon which cost on the order of 600

million dollars or so and mapped the moon much better than we've mapped our planet.

We've sent missions to Mars, many missions to Mars.

Each one of those missions cost between two and three billion dollars.

And so we have the will to do that.

One way to cut down on cost would be to do it faster, and the good news is that's the

plan.

What started as throwing a weight over the side of the boat has turned into utilizing

acoustic waves.

By sending hundreds of laser-like beams of sound into the ocean and measuring how long

it takes to bounce back, scientists can more accurately image the ocean depths.

We're also trying to develop techniques to speed that up, to do it more quickly.

And to do it maybe with autonomous vessels, vessels that will be more efficient that you

don't have to have a crew on and send autonomous vessels out for months at a time and let them

start collecting the data…

To put out drones that would go out and do it autonomously, that's a new forefront that's

developing at the moment, but that's still in its infancy.

The amount of drones that would need to go out to perform this, that's something that

they're still building on.

So yes, one day in the near future our oceans may be teeming with underwater drones or crew-less

ships, crisscrossing the planet, collecting and sending data that will be transformed

into a 3D map of our oceans.

Which is another hurdle we still need to figure out, what to do with all this data?

There's also a major challenge of trying to mass collect and synthesize this data…

It's one thing to have the data stored on 500,000 hard drives and 500,000 vessels, but

you need to get put all together in the same place.

And one boldly named group, Seabed 2030, is looking to lead that fight.

The collaborative project between the Nippon Foundation and GEBCO, is aiming to gather

all the bathymetric data and produce the world's first highly detailed ocean map, and do it

by 2030.

It's amazing how every time we go out to map in unknown waters, we find something we didn't

know about.

It's that kind of discovery and exploration that really drives at least me in terms of

ocean mapping.

And it's that passion, along with their hard work, that has given those in the community

the ability work with and root for Seabed 2030 and their nearing deadline.

They could certainly use more resources if they're gonna get close to hitting that goal,

but I'm gonna go ahead and commit the least aspiration, I'm gonna hope that they're right

that we'll have the oceans mapped by 2030.

I think, the global initiative to have it done by 2030 is going to be quite an undertaking.

It's going to depend on developing technology and a concerted effort from different players,

but I'm optimistic and I think it will happen at some point.

We need a detailed map of the ocean to better understand the ocean, and to do this we need

people, ships, advanced technology, global cooperation and of course, money.

So, how close are we to mapping the entire ocean?

Well, all eyes are on Seabed 2030 and their goal to have a complete, public map by well,

2030.

We're gonna give it our darndest to do.

It's a very, very ambitious goal.

I'm not sure we will get a hundred percent there but we're certainly gonna make some

strides toward that.

So that's our goal is to see it all mapped by 2030.

Thanks so much for watching another episode of How Close Are We.

If you have any ideas for future episodes, let us know in the comments.

And if you want to watch more Seeker ocean content, click over here to watch the Swim,

an ongoing series about one man's journey to swim across the Pacific Ocean.