Upper panels: height of the velocity sign reversal as a function of “continuum” velocity (left) and “continuum” contrast (right) from the Ba ii profile. The mean value is 330 ± 160 km. Each symbol is an average over a bin with an equal number of data points. Bottom panels: height of the contrast sign reversal as a function of the “continuum” velocity (left) and “continuum” contrast (right) from the Ba ii profile. The average value is 420 ± 130 km.