Results of fitting the C/NOFS drifts to Fourier functions. The plot on the left shows the worst fit with an R² value of 0.58, while the plot on the right shows the best fit with an R² value of 0.99. The black curve shows the median drift values obtained from the cleaned C/NOFS drifts, with error bars showing the average absolute deviation from the median within each half-hour bin. The red curve shows the result of the Fourier fit, and the pink dotted line is the linear offset from the fit that is removed when providing the drifts to the SAMI2 model. Finally, the solid blue line indicates 0 m/s.