Coefficient of variation $\left({\sigma }_{\rho }/\overline{\rho }\right)$ in azimuth as a function of time and height above the disk midplane. The dashed white lines denote the different phases of the encounter. The black lines represent three (solid), four (dotted), and five (dash-dotted) pressure scale heights. The coefficient is calculated for r = 25 AU and r = 70 AU, shown in the top and bottom panel, respectively. The dashed red, orange, and yellow lines denote the median in time of the τ = 2/3 emission surface of ¹²CO and ¹³CO, respectively.