It is sunrise in the Great Pacific Garbage Patch, so we are strapping up our six vessel
cameras.
Right now, we are about 140 West, 33.23 North, in the Great Pacific Garbage Patch,
4-5 days away from any land.
The mega trawl is out, the manta trawl, the drones are up in the sky.
We've got visual surveys going on.
All the GoPros are running.
So for now, everything seems like it's working well.
So this expedition is called the Ground Truth Expedition.
And what we're trying to do here is to ground truth our remote sensing method.
So we developed different ways of observing plastic, using cameras, either from drones
or from vessels.
And what we need to do is, to make sure that those methods are accurate.
So we compare basically observation with the samples that we collect directly in the water.
So we get the truth from the ground.
So that's what ground truthing is about basically.
We've been conducting quite a lot of research already, particularly in the North Pacific
here.
But going forward, obviously, we cannot do that all the time, all year long in every ocean.
So we're trying to find methods to monitor plastic pollution at global scale and systematically
over time.
So to do this, we developed that camera system that basically takes a lot of images of the sea surface
And we have an artificial intelligence algorithm that can detect all the different debris.
And once this is working well, we want to scale up basically and try to deploy those
in different vessels going basically all around the world.
And we can basically build global maps over time of plastic pollution accumulation.
Every GoPro that we attach to a ship's railing is taking about 130,000 pictures a day.
So even that in and of itself is like an insane amount of data that we can now bring back
to our remote sensing lead.
And definitely, I think that's a really scalable technology.
The biggest kind of advantage of using drones like this is that they allow you to get an
aerial perspective of the water and of all the plastic at a high resolution.
What the tether does, is it basically feeds power through that cable to the drone so you
can fly in theory indefinitely.
So since for this particular mission, we're basically just cruising along with the boat,
taking pictures of plastic as it flows by, we don't have to go very far.
So the goal is to get as much data as possible.
And what we can do is feed the data into an algorithm that can search through the water
photographs for bits of plastic,
and then catalog a volume of how much plastic we think is passing the boat before it goes
into the trawl.
The biggest limitation is the fact that it's very hard to process the data in real time.
A lot of the plastic is hard to detect, basically you're watching the live feed through a little
screen, it's hard to detect on that screen.
But as the camera quality gets better, as the live feed gets better, and as our ability
to identify plastic real time improves,
I think that technology has huge potential to go find hotspots.
Once we go in the Great Pacific Garbage Patch, it's quite striking actually, because you're
sailing for maybe four or five days
and the first few days when you leave the North American coastline, you don't see anything
or just really barely like one or two objects floating here and there.
But like from one day to another, you actually start to see a lot.
So there’s quite a very strict boundary to the time you enter this accumulation zone.
But once you're in the accumulation zone, debris is not homogeneously distributed.
There's no plastic island.
It's kind of dispersed all over.
But then what we notice is that on large and small scale, you actually notice that debris
is more or less concentrated.
So you will see some sort of little patch passing through the vessel.
And that's what we call hotspots.
We're trying to understand how those debris sort of accumulate at smaller scale.
So during this expedition, we had our crew back on land in Rotterdam, that were running
numerical models on a daily basis
and giving us reports of where we thought we could find hotspots of plastics.
And it's really important that we try to understand this, because if we are able to predict the
formation of those hotspots,
then we can give this information to our cleanup system and operation offshore.
And obviously that will make our cleanup much more efficient, will save on time, on cost,
on energy.
So this is what we're trying to chase.
It's always surprising to see how much plastic we find in our nets on a micro scale.
The macroplastic you kind of see from the bridge or from the deck.
but unless you're in the water or you're sampling with a net that's designed to sample microplastics
you have no idea how much really small stuff is floating around in the water around you.
And I think that always just blows my mind that after 30 minutes, you can come back with
a full codend of your net that's just filled with this very depressing confetti
and yeah, it leaves a bad feeling because you know, that the problem is so much bigger
than we can actually visualize.
And then I think we’re continuously kind of curious about to sample for microplastics
and nanoplastics at depth
so we're lowering down pumps with a very fine mesh and pump for microplastics and nanoplastics
and see whether the continuous fragmentation of larger objects is resulting in the smaller
objects sinking to lower parts of the water column.
This is going to go 2.5 kilometers down, which is as much wire rope as we have, so pretty deep.
Well we've got quite some work now, this was the fun part, being on the ground.
But obviously there's two components.
We have to go through the samples we collected.
So that means we're going to have to count and weigh and classify all the different plastic
particles and plastic objects we collected with our trawls.
And at the same time, we have to go through all the footage we collected with our cameras.
So obviously the idea is to make some estimate of concentration, but also try to compare
the different concentrations estimated by the cameras and by the trawls and see if we
get similar results.
I'm just really curious.
I can say from like a tactile experience how much plastic I think is out here at a time.
But of course, we have all of these techniques that aren't tactile.
By definition, they're supposed to be, you know, removed from that.
So I'm interested to see both whether we can see all the same plastic as we actually caught
in our nets.
And if the way that we process those images is reliable enough that we can say: “Oh,
look, there's that crate that the drone picked up and the GoPros picked up and we caught
with the mega trawl”.
You know, that would be awesome.
That's something that I'm hoping to see.