More than 1000 rivers account for 80% of global riverine plastic emissions into the ocean
Year of Publication
The model approach developed using various data inputs to estimate the probability of plastic waste reaching the ocean via rivers, revealing that more than 1000 rivers are responsible for 80% of global annual emissions, with small urban rivers being the most polluting, highlighting the need for targeted mitigation strategies.
Lourens Meijer, Tim H.M. van Emmerik, Laurent Lebreton, Christian Schmidt
Measurement (System/Market/Tool), Primary Data, Strategy
Purpose of Measurement:
Understanding the Problem, Monitoring and Evaluation
Material Flows, Climate, Policy
Plastic waste increasingly accumulates in the marine environment, but data on the distribution and quantification of riverine sources required for development of effective mitigation are limited. Our model approach includes geographically distributed data on plastic waste, land use, wind, precipitation, and rivers and calculates the probability for plastic waste to reach a river and subsequently the ocean. This probabilistic approach highlights regions that are likely to emit plastic into the ocean. We calibrated our model using recent field observations and show that emissions are distributed over more rivers than previously thought by up to two orders of magnitude. We estimate that more than 1000 rivers account for 80% of global annual emissions, which range between 0.8 million and 2.7 million metric tons per year, with small urban rivers among the most polluting. These high-resolution data allow for the focused development of mitigation strategies and technologies to reduce riverine plastic emissions.