Fig. 1

Sensitivity of parameters on the deduced microplastic abundance. (a) The relationship between the Level 2p data (solid line) and the same data but for the terminal rise velocity of 0. 009 m s^− 1 (dash-dot-dash line) and 0.019 m s^− 1 (dashed line). (b) The relationship between the Level-2w1 data (solid line) and 2w2 data (dash-dotted line)