Instantaneous mixing efficiency
= Instantaneous mixing efficiency
{title2=$\eta(t)=M/(M+\epsilon)$}
Instantaneous mixing efficiency is the fraction of instantaneous irreversible mechanical-energy loss that raises <background potential energy>, after subtracting internal-to-potential exchange. The ratio $\Gamma=M/\epsilon$ is a different quantity, related by $\eta=\Gamma/(1+\Gamma)$. Replacing $M$ by buoyancy exchange $B$ additionally assumes negligible change of <available potential energy>.