The rise in ocean plastics evidenced from a 60-year time series

Abstract

Plastic production has increased exponentially since its use became widespread in the 1950s. This has led to increased concern as plastics have become prevalent in the oceanic environment, and evidence of their impacts on marine organisms and human health has been highlighted. Despite their prevalence, very few long-term (>40 years) records of the distribution and temporal trends of plastics in the world's oceans exist. Here we present a new time series, from 1957 to 2016 and covering over 6.5 million nautical miles, based on records of when plastics have become entangled on a towed marine sampler. This consistent time series provides some of the earliest records of plastic entanglement, and is the first to confirm a significant increase in open ocean plastics in recent decades.

Fig. 1

Total macroplastic and natural counts of entanglement. a annual counts of macroplastic = light blue bars (significant trend = 0.057 ± 0.0066 (1S.D.)), and natural items = grey bars (non-significant trend = 0.0045 ± 0.0028 (1S.D.)). The cumulative sum of the total counts of macroplastic are plotted on the second y-axis in green. b total counts of macroplastic per decade plotted as a box and whisker plot, where the median is represented by a blue circle, the edges of the box are the 25th and 75th percentiles, the whiskers extend to the most extreme data points, and outliers are plotted individually as red crosses. Please note there are only 3 years of data for the 1950s (1957–1959) and only 7 years of data for the 2010s (2010–2016). The annual counts of entanglements observed have been normalised to a percentage frequency of occurrence per Continuous Plankton Recorder tow (%)

Fig. 2

Map of macroplastics in the North Atlantic and adjacent seas. Map showing the location of Continuous Plankton Recorder samples since 1957 shown as grey points, black circles = macroplastic occurrence that has not been categorized, red circles = netting, blue circles = line, yellow circles = rope, green circles = bag, pink circles = monofilament, and cyan circles = string. The location of the two earliest records of macroplastic are annotated with the year they were recorded and black arrows. Note: The white area are where no data are available

Fig. 3

Annual macroplastic counts in categories from 1957 to 2016. Timeseries plot for four categories (total, fishing specified, fishing not specified, bag specified) of macroplastic entanglements from 1957 to 2016, with all macroplastics observed included in the total category. The annual counts of macroplastics observed have been normalised to a percentage frequency of occurrence per Continuous Plankton Recorder tow (%)