  Breaking surface waves generate drops of a broad range of sizes that have a
significant influence on regional and global climates, as well as the
identification of ship movements. Characterizing these phenomena requires a
fundamental understanding of the underlying mechanisms behind drop production.
The interscale nature of these mechanisms also influences the development of
models that enable cost-effective computation of large-scale waves. Interscale
locality implies the universality of small scales and the suitability of
generic subgrid-scale (SGS) models, while interscale nonlocality points to the
potential dependence of the small scales on larger-scale geometry
configurations and the corresponding need for tailored SGS models instead. A
recently developed analysis toolkit combining theoretical population balance
models, multiphase numerical simulations, and structure-tracking algorithms is
used to probe the nature of drop production and its corresponding interscale
mass-transfer characteristics above the surface of breaking waves. The results
from the application of this toolkit suggest that while drop breakup is a
somewhat scale-nonlocal process, its interscale transfer signature suggests
that it is likely capillary-dominated and thus sensitive not to the specific
nature of large-scale wave breaking, but rather to the specific geometry of the
parent drops.
