Cool and Freshwater Skin of the Ocean During Rainfall

Authors

Peter Schlüssel, University of Colorado at Boulder; Universität München - Munich, Germany
Alexander Soloviev, Nova Southeastern UniversityFollow
William J. Emery, University of Colorado - Boulder

ORCID

0000-0001-6519-1547

Document Type

Article

Publication Title

Boundary-Layer Meteorology

ISSN

0006-8314

Publication Date

3-1997

Keywords

Air-sea interaction, Cool skin, Freshwater skin, Rainfall

Abstract

Rainfall over the sea modifies the molecular boundary layers of the upper ocean through a variety of different effects. These cover the freshwater flux stabilizing the near-surface layer, additional heat flux established due to rain versus surface temperature differences, modification of physical parameters by temperature and salinity changes, enhancement of the surface roughness, damping of short gravity waves, surface mixing by rain, and transfer of additional momentum from air to sea. They are separately described and included in our surface renewal model to investigate the rain's influence on the cool skin of the ocean and the creation of a haline molecular diffusion layer. Simulations with the upgraded model show that the most important effect on the conductive layer is that of reduced renewal periods followed by additional surface cooling due to rain on the order of 0.1 K. At rain rates below 50 mm h-1 rainfall is not able to completely destroy the mean temperature difference across the cool skin. A freshwater skin is created that exhibits a salinity difference exceeding 4‰ under strong rainfall. Comparisons with field data of the cool skin taken during the Coupled Ocean Atmosphere Response Experiment confirm the upgraded renewal model. Surface salinity measurements taken during the same field campaign are consistent with the calculated salinity differences across the freshwater skin. The enhancement of surface roughness by natural rain is less pronounced than described in earlier laboratory studies of rain with large drop sizes only.

DOI

10.1023/A:1000225700380

Volume

82

Issue

3

First Page

439

Last Page

474

Comments

©1997 Kluwer Academic Publishers.

The final publication is available at Springer via http://dx.doi.org/10.1023/A:1000225700380.

Additional Comments

NASA contract:NAGW-1110; German TOGA COARE contract:03F0088B

NSUWorks Citation

Peter Schlüssel, Alexander Soloviev, and William J. Emery. 1997. Cool and Freshwater Skin of the Ocean During Rainfall .Boundary-Layer Meteorology , (3) : 439 -474. https://nsuworks.nova.edu/occ_facarticles/648.