Vanishing Horizontal Sea Surface Temperature Gradients at Low Wind Speeds

Authors

Kristina B. Katsaros, National Oceanic and Atmospheric Administration
Alexander Soloviev, Nova Southeastern UniversityFollow

ORCID

0000-0001-6519-1547

Document Type

Article

Publication Title

Boundary-Layer Meteorology

ISSN

0006-8314

Publication Date

8-2004

Keywords

Climate, Diurnal warming, Horizontal temperature gradients, Remote sensing, Sea surface temperature

Abstract

Sea surface temperature (SST) is a result of multiple interactions in air-sea processes. During days with strong insolation and low wind speed, there may be uneven net heating of the water layer near the surface of the ocean, when there are horizontal temperature gradients at the sea surface. Cooling of the water caused by evaporation, sensible, or longwave radiative, heat loss would be greater from warm water compared to that from relatively cold water. As a result, under low wind speed conditions and clear skies, the horizontal SST discontinuities, occurring at fronts, eddies, or in storm wakes, may diminish or even vanish. This phenomenon is illustrated here with some field and modelling results. The dependence on latitude and mean environmental conditions of the difference in warming on the cold and warm side of SST discontinuities is explored. The time dependence is important for the impact on remote sensing of SST, and it is found to be short enough that substantial masking of SST gradients can occur during the first six hours of the diurnal heating cycle, but the effect would continue to grow if calm and solar heating persist for several subsequent days. An integrated effect of this uneven net heating is seen in the seasonal masking of subsurface temperature gradients in the Gulf of Mexico and Florida Straits.

DOI

10.1023/B:BOUN.0000027905.90989.b2

Volume

112

Issue

2

First Page

381

Last Page

396

Comments

©2004 Kluwer Academic Publishers

The final publication is available at Springer via http://dx.doi.org/10.1023/B:BOUN.0000027905.90989.b2

Additional Comments

NASA grant #s: NAS6-2996, NAG-1-149; NOAA grant #: NA 86GP0233; NSF grant #: OCE-9730643

NSUWorks Citation

Kristina B. Katsaros and Alexander Soloviev. 2004. Vanishing Horizontal Sea Surface Temperature Gradients at Low Wind Speeds .Boundary-Layer Meteorology , (2) : 381 -396. https://nsuworks.nova.edu/occ_facarticles/653.