Wed April 17, 2013
Dr. Giora Proskurowski, University of Washington – Plastic in the Oceans
In today’s Academic Minute, Dr. Giora Proskurowski reassesses the amount of plastic pollution being held in the world’s oceans.
Giora Proskurowski is a research scientist with the Interactive Oceans program at the University of Washington. He earned his Ph.D.in chemical oceanography from the University of Washington, where he studied the connections between biology, geology, and chemistry at deep-sea hot vents. He has also served as a as a postdoctoral scholar and Visiting Investigator at the Woods Hole Oceanographic Institution in Woods Hole, Massachusetts.
Dr. Giora Proskurowski – Plastic in the Oceans
I am an oceanographer and a recent focus of mine is the study of plastic pollution in the oceans. Over the past several years I have spent many months on research vessels in the middle of the North Pacific and North Atlantic collecting and analyzing millimeter sized plastic fragments skimmed from the surface of the water. At the center of the major ocean basins--at about 30°N and S latitudes--there are large regions of persistently high atmospheric pressure. These conditions—the same ones that make vacationing in Hawaii or Bermuda so pleasant—result in low winds and currents that trap plastic debris. These “subtropical gyres” are the end of the line for humanity’s waste stream stuck in a holding pattern thousands of miles from the nearest continent.
Imagine exploring the Amazon rainforest and bushwacking for several days to a place never before visited by humans. Then imagine looking upwards and seeing hundreds of plastic bags caught in the branches of the trees. There are striking parallels between that imagined scenario and the real one I’ve found hundreds of times--leaning over the side of a boat in the middle of the ocean, ten days from the nearest port, collecting and analyzing nets full of thousands of tiny plastic fragments.
Marine plastic pollution is a stark reminder that human activity has changed the global ocean in profound ways, and it may be even worse than we previously feared. Some of my recent work shows that in the turbulent ocean plastic particles are not just found at the surface, but at 10, 20, 50 feet below the surface. What this means is that when we sample the surface layer we are only observing roughly half of all the plastic that is actually at that location. As surface nets are the standard method, this has led to an underestimation of the amount of plastic in the ocean.