Nonlinear Processes in Geophysics www.nonlin-processes-geophys.net 1023-5809 1607-7946 1 2/3 1994 10.5194/npg-1-115-1994 http://www.nonlin-processes-geophys.net/1/115/1994/ http://www.nonlin-processes-geophys.net/1/115/1994/npg-1-115-1994.html http://www.nonlin-processes-geophys.net/1/115/1994/npg-1-115-1994.pdf 115 123 0000-00-00 Unified multifractal atmospheric dynamics tested in the tropics: part II, vertical scaling and generalized scale invariance A. Lazarev D. Schertzer S. Lovejoy Y. Chigirinskaya Space Research Institute, Profsoyuznaya pl. 84/32, 117810 Moscow, Russia Laboratoìre de Météorologie Dynamique, Université Pierre et Marie Curie, 4 Place Jussie, 75252 Paris Cedex 05, France on leave from the Physics Dept., McGill Univ., Canada on leave from the Math. and Mech. Dept., Moscow Univ., Russia We empirically investigate the scaling behaviour of the horizontal wind along the vertical direction using 287 radiosonde soundings with a resolution of 50 m. We compare the results obtained with those of the horizontal temporal behaviour in the framework of Generalized Scaling Invariance and the unified Scaling model of atmospheric dynamics. We find the scaling to be very well respected over the range 50 m - 13 km (nearly the entire troposphere) and we estimate the universal multifractal indices which characterize the statistics in the vertical. By comparing our result with those obtained in the horizontal we show that the degree of stratification is different for mean and extreme structures. Finally, we theoretically discuss the necessary improvements to the Unified Multifractal model needed to account for them.