Fighting the Great Pacific Garbage Patch: when design struggles against plastics
Pubblicato il 12 gennaio 2019
Wherever you might have travelled in your life, there is a country where you most likely have not ever been, and probably you will not ever be.
It is located in the Pacific Ocean, right between Hawaii and California. It is best known as an island but actually it is not. And no, we are not talking about Atlantis.
Its foundation took place in 2013 by UNESCO, from an idea of the italian artist Maria Cristina Finucci: since then it has been recognized as the “Garbage Patch State”.
And although it resembles an island in the middle of the ocean, you might not wish to spend your summer holidays there.
The Great Pacific Garbage Patch (GPGP) is not an island
The GPGP has been studied for years and yet is currently under constant observation. To determine the real dimensions is not an easy task because of its chaotic nature, but its usually estimated size is around the twice of Texas’ and three times France’.
Even the precise location is constantly changing, due to interannual variations, winds and currents. And it is not visible via satellite or from the sky, because it mostly floats underwater.
Moreover, we should talk about “patches” rather than a single one, because there is a denser center area but also several patches in the outer region. And these have an high plastics concentration as well, for a grand total of nearly 100000 tonnes.
This overwhelming mass of plastic has been categorized in 4 classes.
- Microplastics: barely visible to the naked eye, it is about objects smaller than 0,5cm, and it accounts for the 8% of the total mass even if it consist of the 94% of the total floating objects.
- Mesoplastics: the class of debris in a range between 0,5 and 5cm.
- Macroplastics: it accounts for easily visible debris over 5cm. Macroplastics have the major mass concentration in the GPGP and they are usually fragments, hard plastics, fishing nets and ropes, etc.
- Megaplastics: macroplastics over 50cm.
From a certain point of view, microplastics are the biggest issue, even if those are a minor part of the overall garbage mass. Indeed they usually are too small to detect and seize, they spread everywhere and they affect the marine life which confuses plastics with food, leading to malnutrition and ingestions of toxic chemicals (PBT, “Persistent Bio-Accumulative Toxic”).
Which eventually, comes to our kitchens end ends up in our stomach.
That said, it does not mean that macroplastics are less harmful. It is rather the opposite.
The sun, the currents, the marine life, they all contribute to the deterioration of big plastic objects, which led to a huge amount of those small pieces of microplastics, so hard to get rid of.
So, if you are planning a cruise into the ocean and you fantasize to step by an unknown island made of bins like a modern age Robinson Crusoe, get ready to be disappointed. Instead, be prepared to swim in a vortex of floating trash. Enjoy the Great Pacific Garbage Patch!
Design and engineering: the Ocean Cleanup project and the neverending war against plastics
The Ocean Cleanup Project is a contemporary fairytail of good against evil in the modern era. Designed by the 24 year old dutch engineer Boyan Slat, the project has been funded for 20 million dollars. They developed a 600m long floater which is able to prevent plastic to flow over it; it also has a skirt which stops the debris from passing below the floater, underwater.
After years of testing led by a team of 70 scientist, the project became fully operational this October, in a general mood of hope and enthusiasm. According to the plans, the Ocean Cleanup would have been able to reduce the Great Pacific Garbage Patch of the 50% every 5 years.
But there is no fairytale without a fierce evil opposition.
And years of testing cannot predict with 100% accuracy what is going to happen in the real environment the project has been designed for.
That’s why the floater has shown from the beginning some problems in retaining the plastics, with the debris escaping after the scooping. The sun-powered barrier was in fact moving too slow to hold efficiently all the plastic. The team started to work on an upgrade of the barrier, making it wider in order to catch more waves and wind to move faster.
Unfortunately, the plot became even harder in the last days, when the company reported that the 600 meters long floating barrier is taking damages in few points. Eventually, a 20 meters portion of the buoy has fallen apart, breaking up with the rest of the body.
Now the team is leading back to Hawaii in order to restore the floater and improve its design: currently, the project has been able to collect over 2 tons of trash in less than one month, and that amount might be doubled with the improvements required to overcome the issues.
Is it the end? No way!
The battle might be lost, the real war has yet to come.