From turtles mistaking plastic bags for jellyfish, to dolphins getting entangeled in discarded fishing nets, and the injection of persistent organic pollutants absorbed into plastics, plastic pollution in the ocean is harmful to marine life.
Eriksen et al have a new paper out about the amount of plastic pollution in the oceans. The Guardian wrote about it, so did Willis Eschenbach at WUWT. No prizes for guessing whose coverage was more accurate.
Eriksen et al report that the world’s oceans contain about 270 thousand tonnes of plastic. Eschenbach divides this mass by the volume of the ocean (1.3 billion km3) and reports that 200 g km-3 is nothing to get passionate about. This is, after all, only an order of magnitude higher than the concentration of gold in the ocean.
However, Eschenbach is straining to mislead the reader. The data Eriksen et al synthesise comes from surface net-tows and visual observations of large plastic debris at the surface. This is data on the uppermost metre (or less) of the ocean, not the entire ocean volume. Consequently, Eschenbach’s estimated concentration is out by at least factor of 3790 (the average depth of the ocean is 3790 m).
Even for WUWT, this is a bad estimate.