  The energy in turbulent flow can be amplified by compression, when the
compression occurs on a timescale shorter than the turbulent dissipation time.
This mechanism may play a part in sustaining turbulence in various
astrophysical systems, including molecular clouds. The amount of turbulent
amplification depends on the net effect of the compressive forcing and
turbulent dissipation. By giving an argument for a bound on this dissipation,
we give a lower bound for the scaling of the turbulent velocity with
compression ratio in compressed turbulence. That is, turbulence undergoing
compression will be enhanced at least as much as the bound given here, subject
to a set of caveats that will be outlined. Used as a validation check, this
lower bound suggests that some simulations and models of compressing
astrophysical turbulence are too dissipative. The technique used highlights the
relationship between compressed turbulence and decaying turbulence.
