TY - JOUR
T1 - Signatures of Air–Wave Interactions Over a Large Lake
AU - Li, Qi
AU - Bou-Zeid, Elie R.
AU - Vercauteren, Nikki
AU - Parlange, Marc
N1 - Publisher Copyright:
© 2018, Springer Science+Business Media B.V., part of Springer Nature.
PY - 2018/6/1
Y1 - 2018/6/1
N2 - The air–water exchange of momentum and scalars (temperature and water vapour) is investigated using the Lake-Atmosphere Turbulent EXchange (LATEX) dataset. The wind waves and swell are found to affect the coupling between the water surface and the air differently. The surface-stress vector aligns with the wind velocity in the presence of wind waves, but a wide range of stress–wind misalignment angles is observed during swell. The momentum transport efficiency decreases when significant stress–wind misalignment is present, suggesting a strong influence of surface wave properties on surface drag. Based on this improved understanding of the role of wave–wind misalignment, a new relative wind speed for surface-layer similarity formulations is proposed and tested using the data. The new expression yields a value of the von Kármán constant (κ) of 0.38, compared to 0.36 when using the absolute wind speed, as well as reduced data fitting errors. Finally, the ratios of aerodynamic to scalar roughness lengths are computed and various existing models in the literature are tested using least-square fitting to the observed ratios. The tests are able to discriminate between the performance of various models; however, they also indicate that more investigations are required to understand the physics of scalar exchanges over waves.
AB - The air–water exchange of momentum and scalars (temperature and water vapour) is investigated using the Lake-Atmosphere Turbulent EXchange (LATEX) dataset. The wind waves and swell are found to affect the coupling between the water surface and the air differently. The surface-stress vector aligns with the wind velocity in the presence of wind waves, but a wide range of stress–wind misalignment angles is observed during swell. The momentum transport efficiency decreases when significant stress–wind misalignment is present, suggesting a strong influence of surface wave properties on surface drag. Based on this improved understanding of the role of wave–wind misalignment, a new relative wind speed for surface-layer similarity formulations is proposed and tested using the data. The new expression yields a value of the von Kármán constant (κ) of 0.38, compared to 0.36 when using the absolute wind speed, as well as reduced data fitting errors. Finally, the ratios of aerodynamic to scalar roughness lengths are computed and various existing models in the literature are tested using least-square fitting to the observed ratios. The tests are able to discriminate between the performance of various models; however, they also indicate that more investigations are required to understand the physics of scalar exchanges over waves.
KW - Aerodynamic roughness length
KW - Air-sea interaction
KW - Air-wave interaction
KW - Marine boundary layer
KW - Scalar roughness length
UR - http://www.scopus.com/inward/record.url?scp=85040799091&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85040799091&partnerID=8YFLogxK
U2 - 10.1007/s10546-017-0329-z
DO - 10.1007/s10546-017-0329-z
M3 - Article
AN - SCOPUS:85040799091
SN - 0006-8314
VL - 167
SP - 445
EP - 468
JO - Boundary-Layer Meteorology
JF - Boundary-Layer Meteorology
IS - 3
ER -