From a clean beach to a clean ocean

Summer in the Netherlands. Sometimes it is extremely humid and cloudy, many times it rains, but there are these days that are just genuinely nice. On these days, regardless of any viruses, beaches are crowded. Ironically, the annual beach cleanup had been cancelled due to COVID-19. So instead, toolkits are handed out to encourage beachgoers to pick up trash.

Last Tuesday we gave a webinar to provide more information on the Galapagos Plastic Free Project. A few people made the remark that by cleaning beaches on the Galapagos Islands we are approaching the plastic pollution problem with an end-of-pipe solution. Yes, it is crucial that measures are taken to stop plastics from entering the ocean. As the Dutch are encouraged to clean up their own waste on beaches, the Ocean Cleanup tries to remove plastics from rivers and governments are trying to implement stricter rules on plastic production and waste management.

However, the plastic that is already in the ocean is likely to stay there for many many years (check out this article). And when plastic washes ashore, it does not necessarily stay on the beach but can re-enter the ocean. So even if from tomorrow onwards no more plastic would enter the ocean, there would still be plastic arriving at the Galapagos Islands in the coming few decades harming wildlife and impacting tourism.

Therefore, beach cleanups are essential. And, if done effectively, they will not only clean the beaches, but also the ocean surrounding the Galapagos Islands. And that specific word ‘effective’ plays a central role in our research.

Let’s have a look at the animation below:

The top panel shows the situation where we decide to clean up those beaches that are most heavily polluted. By removing the plastic from the beach, the Galapagos tortoises might be happy, but the sergeant major fish still have to share their ocean with pieces of plastic. Another option is to instead search for those beaches where the plastic moves back and forth between the beach and the ocean. If we clean these beaches, as you can see in the bottom panel of the animation, we are also cleaning up the ocean. The continuous back-and-forth movement of the plastic pieces between the ocean and beach also leads to plastic degradation due to the constant scrubbing of the plastic against the sandy or rocky beaches. Therefore, an additional advantage of taking away this plastic is the prevention of the formation of microplastics.

A beach with only little beach-ocean plastic exchange has to be cleaned maybe once a year, whereas a beach with strong beach-ocean plastic exchange should preferably be cleaned every week. It is our task to predict what is happening at which beach, so park rangers and locals know when, where and how often to cleanup. Stay tuned for how we will do this using observations, ocean models and a plastic transport model!