Quantifying energy dissipation due to wave breaking remains an essential
but elusive goal for studying and modeling air-sea fluxes of heat, gas,
and momentum. Previous observations have shown that lifetimes of bubble
plumes and surface foam are directly related to the dissipated energy.
Specifically, the foam decay time can be used to estimate the timescale
of the subsurface bubble plume and the energy dissipated in the breaking
process. A mitigating factor is that the foam decay time can be
significantly affected by the surfactant concentration. Here we present
an experimental investigation of a new technique that exploits the
thermal signature of cooling foam to infer wave breaking dynamics. The
experiments were conducted in a laboratory wave tank using artificial
seawater with and without the addition of a surfactant. We show that the
time from the start of the breaking process to the onset of cooling
scales with the bubble plume decay time and the dissipated energy, and
is not significantly affected by the presence of additional surfactants.
We confirm observations from the field of the spatial variability of the
temperature of foam generated by an individual breaking event, which has
implications for inferring the spatial variability of bubble plume
depth.