Free convection scaling

From AMS Glossary
Jump to: navigation, search


free convection scaling

Velocity and length scales that apply to the atmospheric boundary layer during conditions of a statically unstable atmosphere with vigorous thermal circulations and negligible shear-generation of turbulence, such as during a sunny day over land with calm winds.

The length scale is zi, the mixed-layer depth, and the velocity scale is w* the Deardorff velocity. A free convection timescale can be created as t* = zi/w*. A free convection temperature scale
ams2001glos-Fex07
can be found using the surface kinematic heat flux,
ams2001glos-Fex08
. Similar scales can be generated for other variables such as humidity.

Stull, R. B. 1988. An Introduction to Boundary Layer Meteorology. 666 pp.

Personal tools
Namespaces
Variants