Clumping,
or random density inhomogeneities
Creates a porous wind,
potentially with paths having lower column densities (but other
paths higher, if mass is conserved)
Can reduce average optical
depth of the wind appreciably only if individual clumps are
optically thick: Then the atomic cross section in the opacity is
replaced by the physical cross section of the clump
Clumps would therefore have to be quite
large
Non-isotropic clumping can have an
effect on line profiles…