Figure 6.

Schematic representation of the important length scales of the system. Both viscous (δ) and thermal (ξ) penetration depths and the geometry of the system are marked. While the lateral density wave propagates along the x-y plane, oscillations both in density and in temperature decay exponentially along the z direction. The density length scale (δ) is of the same order or larger than the thermal penetration depth (ξ), and therefore proposes negligible dissipation of heat into the bulk water.