We are Boyan Slat and Laurent Lebreton, the founder and the Lead Oceanographer of The Ocean Cleanup. We just published the most comprehensive study on the Great Pacific Garbage Patch. AMA!

What can we do to help, except from using less plastic and give money?

And by the way: thank you so, so much for your idea and your enthusiasm. I really admire your work.

Laurent: Thank you! You can also get involved, find local beach cleanup initiatives if you live by the sea or river cleanup if you are in land. I always tell people, if you go to the outdoors, bring at least three pieces of trash back with you. Boyan: + we're always looking for smart people to join our team - see our current vacancies on https://www.theoceancleanup.com/careers/

Hi! I love your project:) I read somewhere, I think it was a Nature paper, that something like 80% of all microplastics ending up in the ocean originate from 10 major rivers. Would it be possible to set up one of your plastic removal filter things you use in the ocean in each of these rivers? good luck with your project!

plastic removal filter things

Great naming suggestion, btw

Boyan: We did an article on this last year, see: https://www.nature.com/articles/ncomms15611

Our cleanup systems are designed to work in the deep open ocean so wouldn't work in rivers, but we do have a few ideas for this, which we hope to be able to work on in the future...

Do you believe we will someday be able to fully eliminate the Great Pacific Garbage Patch?

To solve the problem, we need to do two things: stopping the inflow and removing the accumulated mass. With our upcoming cleanup, we aim to remove 50% of the patch every 5 years. However, what will happen is that we'll be 'thinning out' the patch, meaning that it takes as much time to go from 0 to 50% removed as from 80% to 90% removed. Therefore, we would never be able to remove every last piece of plastic from the patch, but we are confident our target of a 90% reduction by 2040 is possible. ^Boyan

Hi guys, the best £20 I ever spent was your crowdfunding campaign years ago. This project seems to be going from success to success - thanks for all your hard work. What are the biggest obstacles that remain? Thanks

Boyan: thanks for your support! Well, obviously we haven't cleaned the ocean yet, so plenty of challenges remain. The most important thing on the road to success is to get cleanup system #1 to work. Because of the scale of the system and the unpredictability of the ocean, there are plenty things that can go wrong. Either way, it's going to be an exciting 12 months ahead...

What percentage of the garbage patch is composed of recyclable waste? And, do you think there are recycling methods on the horizon for the waste that cannot currently be recycled? Would this not be dissimilar to concepts such as "landfill mining"?

Boyan: in principle all the plastic we'll collect from the patch is recyclable. However, there is a wide range of qualities, and the lower the quality, the most it costs to process. About half of the plastic is good enough for mechanical recycling, while the other halve's polymer chains are too oxidized and would require a thermal or chemical route. We'll share more on this once we have the first plastic back in port.

What's the step after cleaning the ocean? What will happen to the plastic debris collected? How can we (as a society) reduce the inputs of marine debris in the next years?

Boyan: the main problem we try to solve is how to collect the plastic from the GPGP in a way that's as fast, as cost-effective and as effective as possible. That's the hardest part. Once the plastic is collected, it will be shipped to land where we will recycle the plastic, likely into new products. None of it will end up in a landfill. We'll announce more on these recycling plans once we have the first cleanup system up and running. Regarding your last question; to prevent plastic from entering the ocean, it can be intercepted at various levels, starting at production/consumption, followed by improved waste infrastructure, and as a last step it could be intercepted in rivers and waterways before the plastic becomes ocean plastic. We may explore something for the latter in the future, once the GPGP cleanup is up and running

How often will you need to go to the garbage patch to clean the system from what it collected? How many/how big ships will you need each time? What will be the amount of plastic collected on each of these trips?

(Thanks for what you're trying to achieve, and thanks for the inspiration you provide)

Boyan: for system #1 we have scheduled a plastic collection cycle of 1.5 months. We'll see if that's enough!

When will the first collecting-machine-thing (do you have a cool name for it?) be set into the ocean? I heard it was promised to do so by may of this year, will you be able to archive this?

Boyan: According to our 'all goes well planning', Cleanup System #1 is set to be deployed for the first time by late May. This will still be a trial run (240NM off the coast of California) to check the system behaves well. The real launch, to the patch, is scheduled for July/August this year. PS we still welcome naming suggestions!

How did all the garbage get into the ocean and is there anything I can do to prevent more garbage from getting there?

Laurent: Plastic comes from land (the coast or from rivers) or from the sea (fishing, shipping, aquaculture...). As an individual, you can try not to use that much single use plastic and be careful not to litter. Ocean plastic pollution starts in the street!

Hi Boyan and Laurent,

In terms of long-term operation, will you have crews actively monitor/guard each cleanup system? Things such as rogue shipping containers or other ships/boats come to mind which could potentially damage the cleanup systems.

Thanks for all that you’re doing!

Boyan: The systems will operate autonomously - satellite-connected sensors allow us to monitor the health of all systems. For this year's Cleanup System #1 we will have a vessel next to it for the first 6 months to gather additional data to help us improve the design.

How do you guys make sure the cleanup systems keep clear from all the traffic that is at sea?

Boyan: the systems will be fitted with basically everything we can do to ensure vessel know it's there, including AIS transponders, lights and radar reflectors. Having said that, the chances of our systems coming across vessels are pretty small; on average there are just 5 vessels in an area 3x the size of France.

Hi guys, in terms of the potential success of the ocean cleanup project. Will this have a significant impact on ocean wildlife populations?

(You guys rock, keep the up the incredible work!)

Boyan: because our system moves through the ocean very slowly (10 cm/s average) and we use screens instead of nets, the system is designed to be safe for marine life. A full environmental impact assessment is coming out soon, but is looking good so far.

How do you feel about the outcome of your research?

Laurent: our study helps the research on marine litter go one step further. It's an interesting science where the more you look the more you find. The numbers speak by themselves, it is good to see the outreach of the study as more and more people are becoming aware of the issue. Boyan: the results really underline the urgency to act; right now, less than 1% of the mass of the patch is smaller than 1.5mm. If we let the other 99% of the patch left to fragment, it would of course be in a pretty bad situation.

What is the oldest piece of plastic that you have found in the ocean?

Laurent: the oldest identified object was a crate from 1977. Although that doesn't say if this really was the oldest one as many were unrecognizable fragments.

What challenges do you foresee for addressing the Great Atlantic Garbage Patch, or for any GP in any of the gyres?

Boyan: the other patches contains much less plastic, so the cost per mass of plastic collected would obviously be higher. For the North Atlantic, how to deal with the presence of sargassum would be something we'd need to figure out.

Do you have any idea how fast the larger garbage patches can be shrunk by your methods of removal?

Boyan: this is really budget-dependent; the more systems you deploy, the faster you clean. To get to our target of a 50% reduction in 5 years, and a 90% reduction by 2040, we currently estimate we'll need a fleet of 60 cleanup systems.

Hi, thanks for the opportunity! Are or will be the raw survey data available? I have ideas to digest the data with visualizations, similarly what Real World Visuals guys do: https://www.youtube.com/watch?v=_M4kTvKRYC4 ... or similar style you did earlier: https://www.youtube.com/watch?v=jS2RZz3Gk_k I think these kind of visualizations can make the sense more in terms of public engagement. In contrast with abstract/cartoony visualizations and infographics these have much more connection with the reality.

Laurent: Our data collections from field expeditions are publicly available here: https://figshare.com/articles/Supplementary_data_for_Evidence_that_the_Great_Pacific_Garbage_Patch_is_rapidly_accumulating_plastic_/5873142

Always love a good data visualization!

I recently read an article about a study that found particles of plastic not only in water, but also the air we breathe. To some degree, we've already seen some of the effects on wildlife, but what about humans?

Laurent: we find plastic everywhere from Arctic to Antarctic, from sea surface to seabed, on land and in the atmosphere. A recent presentation last week at the International Marine Debris Conference in San Diego was talking about plastic fibers found in beers :/ I am not aware of evidence of direct harm on human from ingesting plastic BUT some persistent organic pollutants (POPs) found on ocean plastic for example are know to have adverse consequences on organisms including mammals AND also the science is very young: plastic was only introduced in the 50s in our societies.

Do you plan to continue measuring ocean plastic through mega expeditions and aerial surveys after the barriers have been deployed? If so, how frequently?

I imagine it's quite expensive to do either the 30-boat mega expedition or the aerial survey, but both produced compelling data in the video. I would guess this would be valuable for continuously improving the system, but perhaps it's enough to monitor the captured plastic by the barriers?

Laurent: A monitoring vessel will be following the first system as we deploy it in the North Pacific. This will be a great opportunity to conduct additional research as well as measure the efficiency of the barrier. As a teaser, we are currently experimenting with drones and underwater deployment. Also working closely with partners on an European Space Agency projects to observe marine litter from space.

First of all, congratulation on the very scientific approach to the problem.

Has your view of how much can be cleaned changed from the TED days?

You mentioned then that the Ocean could be cleaned in 5 years, (or was it 7 years?), knowing what you know now, do you think it is still a realistic time frame? Can we ever claim to have 'cleaned the ocean'?

Boyan: How much can be cleaned is primarily a question of budget; if you want to clean more/faster, just deploy additional systems. The performance benchmark of removing 50% in 5 years (as I mentioned during the 2012 talk) is still the benchmark we go for - the big difference is that, thanks to the modularity of the current design, we can start sooner and operate at lower cost.

Was all that research really necessary just to fish plastic out of the sea?

Boyan: back when we founded The Ocean Cleanup, we had no idea until what depth the plastic reaches, how much is out there and how large it is. It's pretty important to know these things if you want to develop a good cleanup technology.