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Leonel Romero, W. Kendall Melville, and Jessica M. Kleiss

orthogonal one-dimensional wavenumber k 1 and k 2 spectra with k 1 approximately aligned with the local winds, covering a wider range of wavenumbers, with an upper wavenumber limit of 2 rad m −1 . The fixed lidar measurements showed that at sufficiently high wavenumbers the directional spectrum is consistent with an isotropic form with , and the proportionality constant showed little or no dependence on the external forcing, in good agreement with the observations by Banner et al. (1989) at

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Leonel Romero and W. Kendall Melville

coefficient by supporting wave-induced stresses ( Janssen 1989 ). For example, Banner and Melville (1976) and Banner (1990b) showed experimentally that airflow separation over steep breaking waves can enhance the momentum transfer when compared to attached flows. More recently, based on field observations, Grachev and Fairall (2001) showed that swell traveling faster than the wind may result in a momentum flux from the ocean waves to the atmosphere. In the mid-1900s, the study of surface waves

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Jessica M. Kleiss and W. Kendall Melville

coverage W A in Fig. 8b is limited to image sequences that underwent kinematic processing, all from roughly 400-m altitude, reducing the number of observations. Each colored circle in the figure represents the average whitecap coverage of sequential images that cover roughly 3 km 2 of nonoverlapping sea surface area. The color indicates the effective wave age c p / u * e . The wind and wave data have been spatially interpolated from the locations of radome wind and scanning lidar wave

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Shi Jiang and Michael Ghil

data only were used than when geopotential observations only were made (see also Fig. 5 in Ghil 1989). Using the calculus of variations along with a geostrophic constraint, Phillips (1983) derived a formulato estimate the critical accuracy for a satellite lidar winddetector such that the combination of satellite windswith satellite temperatures yield analyses with an accuracy equivalent to that obtained from a standard rawinsonde network. For the sake of consistency with thepresent context, the

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Edward J. Walsh, David W. Hancock III, Donald E. Hines, Robert N. Swift, and John F. Scott

, Maryland(Manuscript received 29 December 1986, in final form 12 December 1988)ABSTRACT The Surface Contour Radar (SCR) is a 36-GHz computer-controlled airborne system, which produces oceandirectional wave spectra with much higher angular resolution than pitch-and-roll buoys. SCR observations Ofthe evolution of the fetch-limited directional wave spectrum are presented which indicate the existence of afully-developed sea state. The JONSWAP wave growth model for wave energy and frequency was in

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Jacob M. Steinberg, Noel A. Pelland, and Charles C. Eriksen

( McWilliams 1985 ; D’Asaro 1988b )—are a distinctive class of long-lived eddies capable of trapping and transporting core waters for many months over hundreds of kilometers ( McWilliams 2016 ). Their ubiquity, potential role in the transfer of energy from large to small scales, and ability to redistribute bulk quantities of heat, salt, and nutrients motivates the study of their behavior and evolution. The prevalence of SCVs has been recognized through frequent observations that are often unintentional (e

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Paul A. Hwang and David W. Wang

airborne topographic mapper (ATM: an airborne scanning lidar system). The directional resolution derived from 3D topographic data is considerably better because the dof of the 3D measurements in the space domain is on the same order as the dof of the directional function in the angular domain. The analysis presented in Hwang et al. (2000b) illustrates that the directional resolution for a wave field generated by a steady 10 m s −1 wind field is better than 10° for wavenumber components higher than

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C. Brock Woodson

water column depth to account for reduced upwelling in shallow water. Kirincich et al. (2005) extended these analyses and found reasonable agreement to the Lentz (1994) model for the Oregon coast. Such observations of reduced Ekman transport in shallow water confirmed a limited role of along-shelf winds in driving cross-shelf circulation that scales with distance from the coast. Closer to the coast, cross-shelf winds act to push water in the direction of the wind leading directly to upwelling or

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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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