Frictional Dissipation-Blame It on the Rain

摘要

Frictional dissipation in a turbulent flow occurs when kinetic energy is trans ferred to smaller and smaller scales until it is eventually removed by molecular diffusion. In addition to this turbulent dissi pation, kinetic energy in Earth's atmosphere is also removed in the shear zones surround ing falling raindrops and ice particles. On page 953 of this issue, Pauluis and Dias (7) provide the first observational estimate of the precipitation-induced dissipation and show that its magnitude is comparable to that of turbulent dissipation in air.