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This content will become publicly available on December 1, 2026

Title: Energy and Stability Theory in the Wave-Affected Surface Layer of the Atmosphere
Abstract In this work, we seek to address the validity of Monin–Obukhov similarity theory (MOST) in the wave-affected surface boundary layer of the atmosphere. While bulk flux formulas which rely on MOST have been tested with and applied to measurements and models of air/sea interaction for several decades, the influences of surface wave–mediated fluxes on MOST have not been thoroughly quantified. We assess several months of direct covariance data from a stationary tower deployed with instruments inside the wave-affected surface layer. These measurements are analyzed in the context of the turbulent kinetic energy (TKE) equation and MOST, extending previous work due to the inclusion of directly estimated wave-coherent energy fluxes. Scaled TKE dissipation rates are reduced from what is predicted by MOST during events with large wave-coherent surface fluxes, resulting in a dissipation deficit in the energy budget (roughly 30%). However, we find that shear is much less impacted by these wave events showing much smaller deviations from baselines (less than 10%). During much of the experiment, the dissipation deficit is balanced by the wave-coherent pressure work, suggesting a general understanding of the combined turbulent and wave-driven energetics. However, several large storms in the fall of 2022 yielded much larger dissipation deficits than can be explained by the wave-coherent pressure work, highlighting that more work is needed to understand energetics in the wave-affected surface layer more generally. Significance StatementThe exchanges of heat, momentum, and gases between the air and the ocean are important for weather and climate prediction, ocean simulation, and wave models that are important for safe operations at sea. A current theory for these exchanges was designed for use over land but has been applied successfully over the ocean for several decades. One reason the overland theory [Monin–Obukhov similarity theory (MOST)] may not work as well is due to ocean waves, which change the nature of the surface in comparison with unmoving overland features like hills, mountains, and other topography. In particular, ocean waves grow with the wind, which means that they must draw down momentum and energy from the air above. In this paper, we work to understand why this theory for heat and momentum exchange at the surface (MOST) works well over ocean waves despite the unique physics when compared to wind over land. We find that the influence of waves is visible in some parts of the theory but that for the majority of conditions, the predictions from MOST should work well.  more » « less
Award ID(s):
2023020 2316818
PAR ID:
10652508
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
AMS
Date Published:
Journal Name:
Journal of Physical Oceanography
Volume:
55
Issue:
12
ISSN:
0022-3670
Page Range / eLocation ID:
2515 to 2532
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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