Using a combination of published literature and direct observation, Angelicque White demonstrated that if you look at the actual area of the plastic itself, rather than the entire North Pacific subtropical gyre, the hypothetically ‘cohesive’ plastic patch is actually less than one per cent of the geographic size of Texas.

‘The amount of plastic out there isn’t trivial,’ White said. ‘But using the highest concentrations ever reported by scientists produces a patch that is a small fraction of the state of Texas, not twice the size.’

Another way to quantify the amount of plastic present in the gyre is to look at the ratio of plastic to water. ‘If we were to filter the surface area of the ocean equivalent to a football field in waters having the highest concentration [of plastic] ever recorded,’ White said, ‘the amount of plastic recovered would not even extend to the one-inch [2.5-centimetre] line.’

However, White was keen to point out that the downgrading of the size of the garbage patch was not cause for complacency. ‘If there is a takeaway message, it’s that we should consider it good news that the “garbage patch” doesn’t seem to be as bad as advertised,’ she said, ‘but since it would be prohibitively costly to remove the plastic, we need to focus our efforts on preventing more trash from fouling our oceans in the first place.’

March 2011