In fluid dynamics, turbulence or turbulent flow is a fluid regime characterised by chaotic, stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time. This book presents current research data in the study of turbulence, including topics such as modelling turbulent mixing in the global ocean; investigating the influence of atmospheric turbulence in the reliability and performance of free space optical communication systems; turbulent scales in engineering; local versus non-local processes in turbulent flows; and cosmic rays and astrophysical turbulence.