How much of our trash ends up in the worlds oceans?

As a follow up to last weeks blog this week I have been researching the volume of plastic that is estimated to be in the worlds oceans.

Public environmental literature often states that 8 million tonnes of plastic enter the oceans each year (Parker, 2015).

However within scientific literature the abundance and distribution of marine plastics is often deemed 'unknown'. There are several studies which attempt to clarify estimates, however agreement between papers is often quite dicey.

Jambeck and colleagues from the University of California created a successful model to estimate the abundance of oceanic debris, through the combination of population and economic data from 192 coastal countries. They estimate via the use of per capita production of plastic pollution in coastal countries that the annual input of oceanic pollution as fluctuating between 4.8-12.7 million metric tonnes (MT), with an estimated 9.1 million MT inputted during 2015. If pollution rates continue to increase with population and plastic production growth, then by 2025 they estimate that 155 million MT will be inputted into the worlds oceans. This estimate is over 10 times the quantity of current levels, extrapolated from the same exponential increase in pollution as seen in recent years. Arguably it seems unlikely that exponential increases in plastic pollution will occur given environmental legislation and future mitigation schemes.

Where does all the pollution come from?

There has been a recent shift in where the production of plastic pollution originates. Typically the majority of marine debris originated from more developed countries with high industrial output, whilst less developed more rural economies produced less non organic waste. Industrialisation in developing countries has lead to high levels of plastics and synthetics being produced elsewhere, shifting the spatial source of pollution.

(Parker, 2015)

This chart reflects the highest amounts of plastic waste flowing into the oceans annually. Bangladesh ranks 10th overall, with 867,879 tons inputted into the oceans annually.