# Rain Calms the Sea - The Impact of Entrained Air

## TL;DR

This paper introduces a model explaining how rain-induced air bubbles dampen ocean waves, suggesting rain can calm the sea by increasing wave dissipation through bubble injection.

## Contribution

It presents a novel model linking rain, air bubble entrainment, and wave damping, providing quantitative predictions consistent with experimental data.

## Key findings

- Wave attenuation increases with air bubble presence.
- Predicted dissipation rates match experimental estimates.
- Model relates wave damping to rainfall rate and air-water ratio.

## Abstract

We propose a mechanism for the damping of short ocean gravity waves during rainstorms associated with the injection of air bubbles by rain drops. The mechanism is proposed as one of the possible explanations that ascribe to rain a calming effect on ocean surface waves. A model is developed that shows how wave attenuation increases with the presence of air bubbles in the upper reaches of the ocean. The model makes predictions of the effective wave dissipation coefficient, as a function of the volumetric ratio of air to water, as well as to the rainfall rate. The model predicts dissipation rates that are in line with experimental estimates of the effective wave damping rate.