The data
- The survey. Lebreton, L. et al. (2018). “Evidence that the Great Pacific Garbage Patch is rapidly accumulating plastic.” Scientific Reports 8:4666. doi:10.1038/s41598-018-22939-w. The Ocean Cleanup sampled the patch in 2015 and 2016 with ships towing trawl nets and with aerial survey flights.
- The data files. Published with the paper on figshare, doi:10.6084/m9.figshare.5873142, under a Creative Commons Attribution 4.0 licence. This site uses the modelled concentration map, the patch contours, the trawl catch by debris type and size, the labelled objects, and the historical net-tow dataset.
- Coastlines. Natural Earth 1:110m land, public domain.
How the numbers were made
Size and boundary
The patch is drawn where the modelled mass of floating plastic reaches 10 kilograms per square kilometre, the boundary the study uses. Measuring the area inside that line gives 1.60 million km², matching the paper. The totals of about 80,000 tonnes and 1.8 trillion pieces are the study's own estimates.
On the size comparison, the outline is stored as distances in kilometres from its centre and redrawn wherever you drop it, so it covers the same real area anywhere on the map. The map uses an equirectangular projection, which stretches shapes towards the poles; the land stretches the same way, so the comparison stays fair.
Concentration map
The map shows the study's model of floating plastic of all sizes on a grid of 0.2° cells, about 20 km across. Areas below 100 grams per km² are faded out so the color shows where plastic concentrates. The soccer-field comparison uses a 7,140 m² pitch and counts an empty plastic water bottle as about 15 grams.
Growth over time
The growth chart plots all 3,532 tows in the study's historical dataset, from 1972 to 2016, as grams of small plastic per km². “Typical” means the median tow in each decade, counting tows that caught nothing as zero. Medians are only drawn for decades with at least five tows.
Composition
The count versus weight shares come from about 1.1 million pieces caught in the survey's trawl nets, sorted by type and size and weighed dry. Languages come from 382 recovered objects with readable printing.
Limits
- The survey is a snapshot from 2015–2016. The patch has likely grown since.
- Nets only catch what floats at the surface. Plastic that has sunk or is mixed deeper in the water is not counted.
- The historical tows come from many studies with different nets, mesh sizes and routes, so compare decades loosely.
- The concentration map is a model built from the samples, not a direct measurement of every cell.