This is the first in a series of live blog reports from our correspondent, Olga Mironenko, an environmental scientist focused on marine plastic pollution who is currently aboard a research vessel in the Pacific Ocean sailing from Hawaii to Oregon, USA.
The 10th day of the 33-day-long cruise is a good moment to start putting down my observations so far.
On this research vessel, a ton of oceanographic data is gathered every day by rather costly equipment, which is towed behind us, autonomously deployed and lowered to get the data, and then pulled back up again. The data being gathered by physical oceanographers are a standard set: the salinity, pressure and temperature of water layers, as well as the velocity of the currents we are passing. So the main purpose of the cruise lies within the domain of physical oceanography. (For more details on this the official cruise blog, go here: http://submesoscale.blogspot.com)
My task is somewhat different. I am here to analyze the concentration of plastics of all sizes that we see overboard and in the water samples. I’m trying to get an idea of the degree of plastic pollution in these waters.
So we set sail from Honolulu, and are currently at 25 49.390’ N latitude and 145 34.492’ W longitude, and so far, my observations have been the following.
To my utter surprise, no microplastics have been found in any samples so far. These samples are always a set of 24 8-liter bottles of seawater, sampled at a depth of 5-140 meters. This way, I can see the presence and distribution of marine plastics throughout the selected range of the water column. In fact, no micro- or macroplastics have been found in any of the samples so far, despite the fact that we are within the North Pacific Subtropical Gyre (NPSG), also known as the North Pacific Garbage Patch due to a very high concentration of marine debris.
Why is that?
My hypothesis so far is that microplastics might be concentrated towards the center of the gyre, which is further to the south from where we are, and would act as a sink for all the debris brought in by the circular clockwise motion of the four currents forming the NPSG: Kuroshio, North Pacific, Californian, and North Equatorial. That is where one would expect plastics to be present throughout the water column in the largest quantities.
And as for macroplastics – they either sink to the bottom or stay on the surface, and are not in the water column itself. But again, that’s just a hypothesis .
By contrast, macroplastics of all shapes and sizes can be seen floating on the surface of the ocean everywhere we look. For lack of opportunity to tow a net behind the ship that would trap debris on the surface, I am doing a visual count of what I see over the side of the ship. Today, for instance, during a period of 7 minutes we were “overtaken” by 12 plastic floating items, predominantly plastic bottles and cans, as well as a few polyethylene labels. We also often see buoys and plastic baskets floating on the surface.
The pattern that I can observe so far in these waters differs from the traditional garbage patch image, as the distance between these plastic items is usually 20-50 meters. Waves and currents seem to be working towards spreading them evenly across the surface. But the consistency of the pattern makes up for that distance: Whenever you take a close look at the ocean around, you will see something being carried by the restless waves.
A reservation has to be made has to be made here: it is not that easy to do a reliable visual count off a big ship due to the distance between the observer and the water, along with the swells going up and down, which sometimes hide things.
But having said that, while I am writing this, we just had a small boat return after recovering the floats, and the news, my friends, is garbage. Garbage everywhere. Bottles, unidentifiable objects, fishing nets, everywhere you look. “Not like you could walk on it but certainly wherever you look you see trash.” And we’re not even in the center of the Gyre.
The news, my friends, is garbage. Garbage everywhere.
Another tendency I’ve noticed: Apart from the macro-objects that are more or less evenly spread in time and space, greeting you on a regular basis, you also get patches of smaller-sized plastic particles, which look like dirt against the gorgeous five-kilometer-deep blue over the side of the ship. These patches come and go as a surprise, quickly and unexpectedly, and never in the areas where I take my samples, which is why I haven’t had a chance to sample a single one yet to see what’s in there. Whenever I get my nets and bottles ready, it is gone.
The crew of our ship say they haven’t seen this much garbage in these waters during their entire lives. I notice that when they hear that I’m here not for fundamental oceanography, but rather to look into marine pollution, they are very eager to share their thoughts on the subject, and it’s always with great concern. They share memories of the 1980s, the pre-MARPOL times when ships dumped trash bags right into the ocean without a second thought, the perception at the time (even among oceanographers and people researching the ocean) being that the ocean is endless and able to absorb limitless amounts of anything.
An engineer here told me a story of how he found himself on the notorious Midway Atoll. (Check out the Midway video on Vimeo, if you haven’t seen it yet. It sheds light on what’s happening to the fulmar population, which despite living so far away from mankind is in fact dying from our plastic garbage.)
A seasoned, suntanned man of over 50, this engineer’s job is to perform all kinds of tough physical jobs (which he does easily) on this ship full of tricky machines and equipment. We started to talk, and when he found out what I’m here for, something changed in his face, the polite smile giving way to an expression of deep concern. He shared what had struck him the most: A story of his visit to the Midway Atoll, and his utter shock at the sight of a place so far away from any civilization and yet suffocating in trash.
Amid waves carrying plastic bottles, plastic baskets, plastic what-evers, and accounts like this first-hand story from Midway, I actually find it extremely encouraging. The people around me care.
OK, off to do more sampling, back with new stories from the field soon!