Fig. 12
From: Sounding out life in the deep using acoustic data from ships of opportunity
Secondary corrections for sound speed and absorption variation. The transect presented in Fig. 9 is used to highlight the nature of corrections. (a) Filtered but uncorrected echogram before applying secondary corrections. (b) Shows filtered and corrected echogram after applying secondary corrections with (c) result correction matrix. Bottom panels show the (d) cumulative mean sound speed and (e) absorption coefficient values used for the correction (Eq. 12), highlighting the nature of (f) range-dependant percentage correction applied to the final data product before depth interpolation. The nominal sound speed and absorption coefficient values used for the correction are highlighted as vertical green lines. In boxplots, the vertical line inside of each box is the sample median. The right and left edges of each box are the upper and lower quartiles respectively. The distance between the right and left edges is the interquartile range (IQR). Values that are more than 1.5 IQR away from the right or left of the box are outliers (red plus sign).
