The impact of rain on ocean surface waves and currents

Laxague, Nathan J. M.; Zappa, Christopher J.

Precipitation is an important component of the interaction between Earth's atmosphere and oceans, modifying air-sea fluxes of momentum, heat, and gas. It has been hypothesized that rain's suppression of ocean surface gravity waves and centimeter-scale wave enhancement should alter the nature of air-sea momentum flux, resulting in increased near-surface current. Here, we use field observations to describe this impact and measure the very near-surface current response to rainfall. During heavy rain, surface-roughening ring waves were generated and longer gravity waves were suppressed; immediately following, the magnitude of the near-surface current increased in response to wind forcing but died as the rain subsided and long waves recovered. These first-of-their-kind field observations indicate that rain reduces ocean wave form drag in favor of tangential stress, resulting in the acceleration of current near the sea surface.


Also Published In

Geophysical Research Letters

More About This Work

Academic Units
Lamont-Doherty Earth Observatory
Ocean and Climate Physics
Published Here
January 10, 2022