EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

On the dynamics of a drift flow under low wind

Oleg Druzhinin
Oleg Druzhinin
  • Institute of Applied Physics, Geophysics Dept., Nizhny Novgorod, Russian Federation (

The dynamics of a drift flow in the near-surface water layer driven by a turbulent air wind is investigated by direct numerical simulation (DNS). Comparatively low (up to 2×104) bulk Reynolds numbers of the air-flow are considered when the air boundary layer is turbulent but velocity fluctuations in the water are sufficiently small and the water surface remains aerodynamically smooth. It is shown that a drift flow develops in the near-surface water layer, and its velocity grows monotonically with time. At long times there develops an instability which leads to a saturation of the growth of the drift-velocity. A threshold Reynolds number is defined in DNS under which the drift flow becomes unstable, and a parameterization of the surface drift velocity is formulated in terms of the air-flow friction velocity.

How to cite: Druzhinin, O.: On the dynamics of a drift flow under low wind, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6245,, 2022.