Circularity vs. feret diameter in microplastic particles

A) All particles collected in summer 2009 and fall 2010 (N=32.090). Lines indicate 95% confidence intervals and open circles are outlying data points. B) Median particle circularity by water mass. Unfilled symbols indicate N < 10. Red diamonds = California Current, green squares = transition region, and blue circles = NPSG. Note that water masses should be viewed as highly approximate, since they were estimated using surface trace data only. 

This is Figure 2.10. in the Goldstein 2012 dissertation.