Differentia Rotation of the Sun and Surface Angular Momentum Transport Deduced from Cromospheric Tracers During the Period 1967-77

From the observations daily taken in the H-alpha and K lines at the Catania Astrophysical Observatory, rotation rates and angular momentum transport by Reynolds stresses have been deduced analysing the motion of cromospheric faculae in the 11 years period 1967-77. We found for both H-alpha and K faculae temporal changes of angular velocity showing an avarage increase of the angular velocity with time of about 3%, in agreement with Howard's spectroscopic observations covering the same period. The more compact objects rotate faster than the less compact ones. Angular momentum transport by surface Reynolds stresses also show temporal changes.