Measurements of the viscous tangential stress in the airflow above wind waves

• Published in: Geophysical research letters Vol. 34; no. 19; pp. L19603 - n/a
• Main Authors: Veron, F., Saxena, G., Misra, S. K.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Geophysical Union 01-10-2007; Blackwell Publishing Ltd
• Subjects: Air/sea interactions; Atmospheric Processes; Boundary layer processes; Earth sciences; Earth, ocean, space; Exact sciences and technology; Ocean/atmosphere interactions; Oceanography; Physical; separation; stress; Surface waves and tides; Turbulence; wind-waves; stress; separation; wind-waves; waves; Weather forecast; trend-surface analysis; Wind velocity; global; climate; Long term; Modeling; Air flow; Wavy surface; Drag; winds; Viscous sublayer; Wind wave
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2007GL031242

The stress and drag at the surface of the ocean are crucial parameters for both short term forecasting and the modeling of long‐term global climate trends. However, the partition between viscous, turbulent, and wave stresses, and in particular the effects of airflow separation are not well understood. We present direct measurements of the velocity in the airflow above wind‐generated waves. We observe intermittent separation of the viscous sublayer past the crest of the wind waves leading to dramatic along‐wave variability in the surface viscous tangential stress. These results hold for wind speeds that would normally be considered low to moderate. These viscous stress measurements in the airflow above the wavy surface, and within the separated region are, to the best of the authors' knowledge, the first of this kind.