It is always good for a teacher to take on the role of a student. It is humbling and refreshing to learn new things about science content, life on a ship and yourself. The grad students have been amazingly patient and crazy enthusiastic to share their finds.
But the honeymoon is over, we are at the Patch. Everyone is still wonderfully supportive, but the mood has changed slightly. If we hadn’t found a mess, it would have seemed like a waste of time. Confirming that there is a concentration of plastic in the North Pacific Gyre is both reassuring that they have the skills to find it and depressing to know it exists.
Now the task at hand is to determine how to make sense of it. It isn’t a large island of plastic. It is a soup of bits, pieces and strands. If you look out over the water you see a beautiful cobalt blue ocean. If you look down you see a little bits of things that were once important to someone probably 1,000 miles away.
The researchers are collecting sample after sample of water. Most of the water has plastic in it. With the obvious and already stated fact that the ocean is huge, it is the job of the scientist to put the numbers into perspective. The unrealistic pressure to have a conclusion or solution before we dock in Newport, Oregon next week is on. Right now they are still trying to define the situation. At this point we only have samples.
The CTD, manta net, bongo nets and Oozeki trawl all sample the water a little bit differently. But I will use our primary sampling device, the manta, to describe what one sample represents. A specific amount of water will flow through the manta opening during a timed sampling. The amount of water is determined using a flowmeter. That volume of water will filter through the nets and specimens will collect near the end for you to retrieve. At that point you can only say that you filtered that much water and it had that much stuff in it. There is a very specific sampling protocol you must follow for the sample to be valid. You can only say something about what you collected at that point in time. It takes a lot more runs and some statistical processing to put any weight to your find. We have sampled in the rain, in the middle of a salp bloom, at night, during the day, and under a variety of other conditions. All we can say right now is that plastic is here and here is very, very far away from land.
At numerous areas of the gyre, flecks of plastic are prevalent and easily spotted against the deep blue sea water.
On Aug. 11, SEAPLEX researchers encountered a large net with tangled rope, net, plastic, and various marine organisms attached to it.