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Vernon A. Squire and Fabien Montiel

and Gascard (2016) used airborne scanning lidar observations in the Arctic Ocean to extract the directional wavenumber spectra in the MIZ and found that short waves broaden quickly, while long waves experience little spreading, suggesting scattering and dissipation are dominant at these respective ends of the frequency spectrum. The findings of Sutherland and Gascard (2016) mirror those of Wadhams et al. (1986 , hereinafter WSEP86) , who conducted directional wave measurements in the MIZ

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Jose Henrique G. M. Alves, Michael L. Banner, and Ian R. Young

1. Introduction It has been several decades since the publication of the seminal paper of Pierson and Moskowitz (1964 , hereinafter PM64) on observations of fully developed wind seas and their parameterization. Within this time frame, there has been remarkable scientific progress in wind-wave measurement technology, highlighted by the transition from the single-point time series from shipborne wave-height recorders, as used by PM64 , to present-day two-dimensional spatially extensive sea

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Larry Mahrt, Scott Miller, Tihomir Hristov, and James Edson

distortion and platform motion ( Edson et al. 1998 ; Miller et al. 2008 ), which in turn can contaminate the measured stress divergence. Our study attempts to estimate the surface stress by downward extrapolating flux observations from multiple flux levels near the sea surface. The goal is not to develop a new parameterization but rather to examine the vertical structure of the momentum flux near the surface and examine the impact of the analysis method. Our study analyzes a number of different datasets

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Laurent Grare, Luc Lenain, and W. Kendall Melville

. Details of the telescopic mast are presented in Fig. 2 . The following instruments were mounted on the booms of the R/P FLIP : IMU/GPS (SPAN-CPT, Hemisphere), laser wave gauges (ILM-500), net radiometer (CNR1), and wind lidar (Windcube). Fig . 2. (left) The telescopic mast with (right) details of the different sections. The following instruments were mounted on the mast: sonic anemometers (CSAT3 and Gill R3-50), temperature–humidity sensors (HC2S3), IMU (AHRS400, MTi300), hygrometer CO 2 sensor

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David W. Wang and Paul A. Hwang

-photography and scanning radar or lidar ( Phillips 1958 ; Cote et al. 1960 ; Holthuijsen 1983 ; Jackson et al. 1985 ; Wyatt 1995 ; Hwang et al. 2000 ). The directional bimodality has also been observed in temporal measurements of directional buoys and wave gauges ( Brissette and Wu 1992 ; Young et al. 1995 ; Ewans 1998 ; Ewans and Van der Vlugt 1999 ). However, due to inadequate resolutions of the earlier spatial measurement instruments and controversy over the method-dependent estimations of

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Paul A. Hwang, David W. Wang, Edward J. Walsh, William B. Krabill, and Robert N. Swift

dB. Technology has advanced significantly since those wave mapping missions. Specifically, the aircraft motion can be determined more accurately due to the advent of the kinematic GPS (Global Positioning System) technology. As a result, the signal to noise ratio of the measurement also improved considerably. An airborne topographic mapper (ATM: an airborne scanning lidar ranging system) has been deployed recently for mapping surface waves ( Hwang et al. 1998 ). The dynamic range of the present

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Jim Gunson and Graham Symonds

observations from the North Carolina–Virginia shelf [Shoaling Waves Experiment (SHOWEX)] and Duck, North Carolina (SandyDuck), and output from the WAVEWATCH III model, studied the spectral response of wind-sea growth in a slanting-fetch case, which occurs when the wind blows obliquely off a coast. In such cases, significant wave energy is found up to 75° from the wind direction with low-frequency components propagating alongshore and higher-frequency components, above the peak frequency, aligned with the

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Ryan J. Moniz, Derek A. Fong, C. Brock Woodson, Susan K. Willis, Mark T. Stacey, and Stephen G. Monismith

appropriate, in a strict sense, when the plume length scale falls within the inertial subrange of turbulence wavenumber spectra, which is otherwise only characterized by the turbulent dissipation rate . As shown by Okubo (1971) , for this case the scalar variance and dispersion coefficient take the following forms: where and are numerical constants and defines the characteristic length scale of the distribution for numerical constant . This model has been applied to observations of the 4/3 law on

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W. D. Smyth, J. N. Moum, and J. D. Nash

et al. (2011 , hereafter Part I) report on observations of a persistent narrowband signal in the upper equatorial Pacific from highly resolved measurements of temperature fluctuations on a mooring. This signal was characterized by a spectral peak (at frequency f NB ≃ 0.001 − 0.002 Hz) that was close to N /2 π . The amplitude of the spectral peak varied diurnally (more energetic at night) and was correlated with enhanced turbulence. The signal was vertically coherent over the range of

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Johannes Gemmrich

factor b exists and it has to be determined experimentally. So far, the field studies ( Ding and Farmer 1994 ; Phillips et al. 2001 ; Melville and Matusov 2002 ; Gemmrich et al. 2008 ; Thomson et al. 2009 ) as well as laboratory studies ( Banner and Peirson 2007 ) are inconclusive. To address open issues in the Duncan–Phillips concept we conducted a field experiment that combined visual and infrared observations of the breaking crests with collocated in situ measurements of TKE dissipation

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