Internal boundary layer

From Glossary of Meteorology

internal boundary layer

(Abbreviated IBL.) A layer that forms within an existing boundary layer due to horizontal advection across a discontinuity in some surface property (e.g., aerodynamic roughness length or surface heat flux). IBLs originate at the discontinuity and grow in thickness in the downstream direction until being homogenized with the existing boundary layer via ambient mixing.

Term edited 3 July 2019.

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