2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/117643We show that for long-baseline experiments using a Mt water Cerenkov detector atmospheric neutrino data provide a powerful method to resolve parameter degeneracies. In particular, the combination of long-baseline and atmospheric data increases significantly the sensitivity to the neutrino mass hierarchy and the octant of $θ_{23}$. Furthermore, we discuss the possibility to use $μ$-like atmospheric neutrino data from a big magnetized iron calorimeter to determine the neutrino mass hierarchy.4 pages, 4 figures, talk given at ICHEP06, July 26-August 2, 2006, MoscowHigh Energy Physics - Phenomenologytext