Figure 3

Tropopause height, wind speed at 300 hPa, ζ _TP , horizontal winds at Z _TP , and $N_{\text{max}}^2$ . (a) Height of the lowermost tropopause (Z _TP, color) and wind speed at 300 hPa (contours, m s ⁻¹), (b) ζ _TP (color) and horizontal winds at Z _TP (arrows), and (c) $N_{\text{max}}^2$ at t=36 h. (b) and (c) are only for the tropopause below 14 km.