We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Plastic waste discharge to the global ocean constrained by seawater observations
Summary
Researchers used ocean plastic concentration data combined with multiple ocean circulation models to estimate that approximately 0.7 million metric tons of plastic enter the ocean each year, though uncertainty spans nearly 1.5 orders of magnitude. The study emphasizes that improving emission inventories and ocean monitoring data are the highest priorities for reducing uncertainty in global plastic pollution estimates.
Marine plastic pollution poses a potential threat to the ecosystem, but the sources and their magnitudes remain largely unclear. Existing bottom-up emission inventories vary among studies for two to three orders of magnitudes (OMs). Here, we adopt a top-down approach that uses observed dataset of sea surface plastic concentrations and an ensemble of ocean transport models to reduce the uncertainty of global plastic discharge. The optimal estimation of plastic emissions in this study varies about 1.5 OMs: 0.70 (0.13-3.8 as a 95% confidence interval) million metric tons yr-1 at the present day. We find that the variability of surface plastic abundance caused by different emission inventories is higher than that caused by model parameters. We suggest that more accurate emission inventories, more data for the abundance in the seawater and other compartments, and more accurate model parameters are required to further reduce the uncertainty of our estimate.