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The purpose of the this paper is to apply a new time domain scattering model [1] (not limited to small wave heights, small slopes, or plane waves) to developing seas which may be swell-contaminated and which assume a new bimodal ocean wave directionality function [2]. This attribute of the directionality of the ocean waves is generated through nonlinear wave-wave interaction in which energy near the spectral peak feeds into both, shorter and longer wavelength components. The goal in this paper is to use these new models to further refine current estimations for the magnitude and Doppler characteristics of the acoustic scattering from the sea surface. It is hoped that these revised estimates can be used by other researchers trying to determine the characteristics of other scattering mechanisms expected to be active in the near-surface region of the sea surface.

The scientific objectives for analyzing the CBLAST-Low experiment data are to understand air-sea interactions especially under weak wind conditions by mainly focusing on vertical variations and magnitudes of atmospheric turbulence over oceanic waves within wave boundary layers and marine atmospheric surface layers using the unprecedented dataset. Our objective for FY2007 is to finalize our CBLAST-Low data analysis with many cases as possible, which includes both pilot and main experiment, and both tower and aircraft data. We are in the final stage of preparing a manuscript to be submitted to a journal.

The primary focus of this research is to use large-eddy simulation (LES) and large-wave simulation (LWS) to obtain improved physical understanding of wind-wave-ocean interactions, based on which we aim to develop effective models of wind input and whitecapping dissipation for phase-resolving, nonlinear wave-field simulation at large scales. Our ultimate goal is to establish a numerical capability for predicting deterministically large-scale nonlinear wave-field in real marine environments with the presence of significant wind and wave breaking effects.

The Surface Wave Dynamics Experiment (SWADE) was a large-scale, multi-platform surface wave experiment that was conducted in the southern mid-Atlantic Bight (MAB) off the U.S. east coast during the fall and winter of 1990-1991. The purpose of the experiment was to study the dynamics and evolution of the directional wave field in response to meteorological forcing making use of recent advances in analysis and in situ data collection, numerical wave modelling, and airborne remote sensing. Of the remote sensing instruments participating in the SWADE, the National Aeronautics and Space Administration's Radar Ocean Wave Spectrometer (ROWS) instrument was the most heavily exercised. ROWS collected approximately 45 hr of high-resolution, directional wave spectra and wind speed data on more than a dozen aircraft flights before, during, and after the last intensive observation period (IOP-3). Processed data include 158 spectra files and 88 wind speed files for 12 flights conducted over the period 12 February-7 March, 1991. This report presents all ROWS data that have been processed to date for the SWADE mission. Buoy and model data collected during the St. Valentine's Day frontal episode (14-16 February, 1991) are also presented.

The primary focus of this research is to use large-eddy simulation (LES) and large-wave simulation (LWS) to obtain improved physical understanding of wind-wave-ocean interactions, based on which we aim to develop effective models of wind input and whitecapping dissipation for phase-resolving, nonlinear wave-field simulation at large scales. Our ultimate goal is to establish a numerical capability for predicting deterministically large-scale nonlinear wave-field in real marine environments with the presence of significant wind and wave breaking effects.

Our long term goals are to improve parameterization of surface fluxes in the coastal zone in the presence of wave growth, shoaling, and internal boundary layer development. These goals include improving the present form of similarity theory used by models to predict surface fluxes and stress over water surfaces, and documenting development of internal boundary layers in the coastal zone that are currently not modelled correctly, particularly in cases of flow of warm air over colder water

The principal goal of this project is to improve our understanding of the role of the dissipation source function (Sds) governing the spatial and temporal evolution of surface waves. This will be accomplished through a coordinated modeling effort and using available field data obtained from the Coupled Boundary Layers/Air-Sea Transfer (CBLAST) field experiment augmented by data obtained from the Shoaling Waves Experiment, and controlled laboratory investigations. The results of this study will support the Naval Operational wave forecasting needs for improved accuracy in high wind/wave scenarios.

LONG-TERM GOALS. Existing atmospheric models for predicting surface stress and turbulent structure in the shoaling zone fail because of their inability to properly account for wave age, shoaling, and internal boundary layer development. Accurate model simulation of the surface stress and turbulence above the air-sea interface is important for a number of applications including understanding wave growth and decay. Under this ONR Advance Research Initiative, our goals are: 1. to measure the spatial variation of the wind, surface stress and ocean wave fields in the shoaling zone and to provide quality-controlled data to the shoaling community; and 2. to study the relationship between the spatial varying mean wind, stress, turbulence structures, and surface wave fields in order to model effects of wave age, shoaling, and internal boundary layer development on the drag coefficient and momentum transfer.

Existing normalisations of wave response to prevailing winds remain unreconciled with theoretical predictions. Accurate predictive schemes are essential for the intense storms that are responsible for the most severe wave fields but show signficant complexity as observed by Wright et al. (2001).

Existing normalisations of wave response to prevailing winds remain unreconciled with theoretical predictions. Accurate predictive schemes are essential for the intense storms that are responsible for the most severe wave fields but show signficant complexity as observed by Wright et al. (2001).

Langmuir circulation (LC) and wave breaking are turbulent processes driven by wind and surface waves that are critical in mixing of the ocean surface layer. The effects of LC and breaking waves on upper ocean turbulence are poorly understood, partly because of their mutual entanglement and their interactions with turbulence generated by shear and buoyancy. Utilizing turbulence measurements and a numerical model, we undertake a systematic comparison between observations and simulations of the wave-influenced surface boundary layer. Data sets obtained from the Surface Waves Process Program, the Coastal Mixing and Optics Experiment, and the Coupled Boundary Layers and Air-Sea Transfer experiment provide unique turbulence observations for a wide range of sea and wind conditions. The numerical model is based on a novel large eddy simulation (LES) that incorporates turbulent processes due to LC, buoyancy, shear, and breaking waves, while satisfying the conservation of momentum and energy. Research objectives include quantitative estimates of LC and breaking wave effects in terms of turbulence statistics for a wide range of wind and wave conditions. This work is an important step towards physics-based parameterizations of upper ocean turbulence, which are needed to improve numerical models of weather and climate.

Viewgraphs on presentation of the influence of surface and bottom stress in the coupled ocean circulation and wind-wave models.

The dissipation method is used to obtain estimates for the friction velocity, U>t, as well as values for the neutral drag coefficient, C-^jj, for data collected from a coastal tower off San Diego, California. C-q-^ is found to be independent of the ten-meter height windspeed, U-j^q, for velocities between 4-9 m/sec. Its value is estimated to be (0.94+0.4)10 which compares well with values by Smith (1980) and Large and Pond (1981). Definite trends in C-q-^ with fetch and sea state are also observed. Drag coeffcient estimates are found to be higher for short fetch than for long fetch conditions. C-q^ is also seen to increase sharply just before frontal passages and during sea breeze conditions when the waves are actively growing. With the windspeed and wave field reaching equilibrium, C-q-^ is found to decrease with time to a smaller and more constant value.

The dissipation method is used to obtain estimates for the friction velocity, U>t, as well as values for the neutral drag coefficient, C-^jj, for data collected from a coastal tower off San Diego, California. C-q-^ is found to be independent of the ten-meter height windspeed, U-j^q, for velocities between 4-9 m/sec. Its value is estimated to be (0.94+0.4)10 which compares well with values by Smith (1980) and Large and Pond (1981). Definite trends in C-q-^ with fetch and sea state are also observed. Drag coeffcient estimates are found to be higher for short fetch than for long fetch conditions. C-q^ is also seen to increase sharply just before frontal passages and during sea breeze conditions when the waves are actively growing. With the windspeed and wave field reaching equilibrium, C-q-^ is found to decrease with time to a smaller and more constant value.

This report was prepared to describe the wind and wave conditions that can be expected in U.S. Coast Guard geographical operating areas. The intent is to provide operational program managers a tool to use when considering the potential applications of conventional and advanced marine vehicles (AMVs) to Coast Guard missions. It is also intended to supplement research determining the feasibility of alternate energy sources that involve wind or waves. This work was performed by the National Climatic Data Center under the direction of the U.S. Guard Research and Development Center for the Office of Research and Development.

278 pages ; 17 cm

278 pages ; 17 cm

This study describes the validation of winds fields used in a companion study (Evaluation of global wave prediction at Fleet Numerical Meteorology and Oceanography Center, submitted for review). During this validation, it is found that conventional methods of estimating the distribution of bias across wind speeds can produce widely misleading conclusions. This is demonstrated, and a simple solution (histogram comparisons without geographic interpolation) is presented.

Our long term goals are to improve parameterization of surface fluxes in the coastal zone in the presence of wave growth, shoaling, and internal boundary layer development. These goals include improving the present form of similarity theory used by models to predict surface fluxes and stress over water surfaces and documenting development of internal boundary layers in the coastal zone that are currently not modelled correctly, particularly in cases of flow of warm air over colder water.

We will investigate a number of factors on air-sea transfer of momentum, heat, and moisture under weak wind conditions. We will focus on important impacts of swell amplitude and propagation direction and influences of large atmospheric eddies on turbulence transfer. Improved understanding of the various influences on surface fluxes under weak wind conditions will be used to modify the existing bulk aerodynamic formula.

Our long term goals are to improve parameterization of surface fluxes in the coastal zone in the presence of wave growth, shoaling, and internal boundary layer development. These goals include improving the present form of similarity theory used by models to predict surface fluxes and stress over water surfaces and documenting development of internal boundary layers in the coastal zone that are currently not modelled correctly, particularly in cases of flow of warm air over colder water. Our objectives are to provide quality controlled data sets which include spatial variation of surface fluxes, stress and wave characteristics and provide vertical structure of the wind and thermodynamic variables in the coastal zone. The objectives also include both evaluation of present formulations for surface fluxes at the air-sea interface and evaluation of model simulations of internal boundary layer development.

Our long term goals are to improve parameterization of surface fluxes in the coastal zone in the presence of wave growth, shoaling, and internal boundary layer development. These goals include improving the present form of similarity theory used by models to predict surface fluxes and stress over water surfaces and documenting development of internal boundary layers in the coastal zone that are currently not modelled correctly, particularly in cases of flow of warm air over colder water. Our objectives are to provide quality controlled data sets which include spatial variation of surface fluxes, stress and wave characteristics and provide vertical structure of the wind and thermodynamic variables in the coastal zone. The objectives also include both evaluation of present formulations for surface fluxes at the air-sea interface and evaluation of model simulations of internal boundary layer development.

The dissipation method is used to obtain estimates for the friction velocity U sub *, as well as values for the neutral drag coefficient, CDN, for data collected from a coastal tower off San Diego, California. C sub DN is found to be independent of the ten-meter height windspeed, U sub 10, for velocities between 4-9 m/sec. Its value is estimated to be (0.94 + or - 0.4)1000 which compares well with values by Smith (1980) and Large and Pond (1981). Definite trends in C sub DN with fetch and sea state are also observed. Drag coefficient estimates are found to be higher for short fetch than for long fetch conditions. C sub DN is also seen to increase sharply just before frontal passages and during sea breeze conditions when the waves are actively growing. With the windspeed and wave field reaching equilibrium, C sub DN is found to decrease with time to a smaller and more constant value. (Author)

Operational sites providing near real-time wind-wave and swell measurements are listed for the coastal waters of Australia, as at February 1996. A representative listing of historical data sites is also provided, with a comprehensive bibliography of papers and reports on wave investigations. An introduction to wave conditions around Australia is included. Real-time high resolution digital data are available from moored wave-rider buoys, mostly non-directional, and from fixed platforms used by the oil and gas industry. A coastal radar provide directional wave spectra in Gulf St Vincent. Lower resolution near real-time data are available from satellite altimetry and synthetic aperture radar systems, but not usually within about 80 km of the coast. The JINDALEE over the horizon radar experimental array covers the northwest seas of Australia, and is planned to be expanded to cover the area from Geraldton to Cairns. Spot visual observations of sea conditions are made for beach watch and surf reports, from fixed positions such as lighthouses and oil platforms, and from transiting vessels. The Bureau of Meteorology runs a Wide Area Model (WAM) for deepwater wave prediction, using satellite and ship observations as inputs.

The goal of this work is to develop and evaluate techniques for the retrieval of wind and internal wave (IW) information from marine X-band radar data. While ocean wind measurements are crucial for the transfer of energy and momentum across the air-sea interface, IWs play an important role in tidal energy transport. Marine radars work by transmitting microwave energy from a rotating antenna that also measures the backscatter. The radar backscatter from the sea surface is controlled by the wind-generated small ripple waves through the Bragg-scattering mechanism. Surface winds are thus the dominant factor for generating the radar backscatter. The varying surface current fields associated with IWs interact with the ripples, generating rough convergent and smooth divergent zones. Radars are capable of imaging such IW-induced surface signatures as bands of enhanced and weakened backscatter.

The Long-Term Goals are: 1. Representing surface fluxes and ocean waves in coupled models in the Beaufort and Chukchi Seas. 2. Understand the physics of heat and mass transfer from the ocean to the atmosphere. 3. Improve forecasting of waves on the open ocean and in the marginal ice zone.

This report is a summary of seven data sets produced and archived by the Wave Information Study (WIS) for the Atlantic coast: (1) surface pressure fields, (2) Phase I hindcast wind fields, (3) Phase I deepwater wave data, (4) Phase II hindcast wind fields, (5) Phase II hindcast wave data, (6) Phase III nearshore wave data, and (7) water level data. The wave parameters from the data sets listed in 2, 5, and 6 have been incorporated into WIS's computer-based data system, the Sea-State Engineering Analysis System (SEAS), which is available to all Corps of Engineers personnel. These data sets, except for 1 and 7, have been transferred to the National Climatic Data Center (NCDC) in Asheville, North Carolina. These data may be obtained through Customer Service at NCDC (reference Tape Deck 9787). Originator-supplied keywords: Ocean waves--Atlantic coast--Statistics; Pressure; Winds; Water levels.

https://www.youtube.com/watch?v=M-7A0g8Y0OA

Thesis advisor, Edward B. Thornton

Most present wind, wave, and tidal energy systems require expensive power conditioning systems that reduce overall efficiency. This new design eliminates power conditioning all, or nearly all, of the time. Wind, wave, and tidal energy systems can transmit their energy to pumps that send high-pressure fluid to a central power production area. The central power production area can consist of a series of hydraulic generators. The hydraulic generators can be variable displacement generators such that the RPM, and thus the voltage, remains constant, eliminating the need for further power conditioning. A series of wind blades is attached to a series of radial piston pumps, which pump fluid to a series of axial piston motors attached to generators. As the wind is reduced, the amount of energy is reduced, and the number of active hydraulic generators can be reduced to maintain a nearly constant RPM. If the axial piston motors have variable displacement, an exact RPM can be maintained for all, or nearly all, wind speeds. Analyses have been performed that show over 20% performance improvements with this technique over conventional wind turbines

New calculations of the acoustic wave energy fluxes generated in the solar convective zone have been performed. The treatment of convective turbulence in the sun and solar-like stars, in particular, the precise nature of the turbulent power spectrum has been recognized as one of the most important issues in the wave generation problem. Several different functional forms for spatial and temporal spectra have been considered in the literature and differences between the energy fluxes obtained for different forms often exceed two orders of magnitude. The basic criterion for choosing the appropriate spectrum was the maximal efficiency of the wave generation. We have used a different approach based on physical and empirical arguments as well as on some results from numerical simulation of turbulent convection.

Relaxing mountain audio.

Interest in deep water oil production platform design has increased considerably in recent years. One of the promising concepts for outer continental shelf installations is a semi-submersible, column stabilized floating platform held in place by pre-loaded tendons anchored to the ocean floor. Because of the unique character of the tethering arrangement this concept is commonly referred to as a Tension Leg Platform (TLP). Climatic summary wave and wind data obtained from NOAA ocean data buoys of potential interest in design are summarized. Selected wave and wind data from those storms which produced maximum measured values of significant wave height and modal period is defined. This envelope also identifies seaways of extreme steepness. Characteristic normalized spectra are defined for certain portions of the envelope and in the case of seas of limiting steepness, critical time domain waves are identified. Dynamic response characteristics of a model of the Hutton TLP are reviewed in order to help identify wave and wind data of special interest in determining cumulative service and extreme structural loadings for TLP's. Initiatives for extending the frequency and time domain wave and wind data of this report to individual NOAA data buoy locations are then identified. Keywords: Extreme wave and wind; Mexico Gulf; North Atlantic Ocean.

02-Wind and wave shield I tested my new hand-made Wind shield during a great storm, recorded at the seaside. Marantz PMD661MKII recorder with microphone ST M/S AKG Blue line CK 94 and Sennheiser mkh 416 p48

02-Wind and wave shield I tested my new hand-made Wind shield during a great storm, recorded at the seaside. Marantz PMD661MKII recorder with microphone ST M/S AKG Blue line CK 94 and Sennheiser mkh 416 p48

Global return values of marine wind speed and significant wave height are estimated from very large aggregates of archived ensemble forecasts at +240-h lead time. Long lead time ensures that the forecasts represent independent draws from the model climate. Compared with ERA-Interim, a reanalysis, the ensemble yields higher return estimates for both wind speed and significant wave height. Confidence intervals are much tighter due to the large size of the dataset. The period (9 yrs) is short enough to be considered stationary even with climate change. Furthermore, the ensemble is large enough for non-parametric 100-yr return estimates to be made from order statistics. These direct return estimates compare well with extreme value estimates outside areas with tropical cyclones. Like any method employing modeled fields, it is sensitive to tail biases in the numerical model, but we find that the biases are moderate outside areas with tropical cyclones.

Global return values of marine wind speed and significant wave height are estimated from very large aggregates of archived ensemble forecasts at +240-h lead time. Long lead time ensures that the forecasts represent independent draws from the model climate. Compared with ERA-Interim, a reanalysis, the ensemble yields higher return estimates for both wind speed and significant wave height. Confidence intervals are much tighter due to the large size of the dataset. The period (9 yrs) is short enough to be considered stationary even with climate change. Furthermore, the ensemble is large enough for non-parametric 100-yr return estimates to be made from order statistics. These direct return estimates compare well with extreme value estimates outside areas with tropical cyclones. Like any method employing modeled fields, it is sensitive to tail biases in the numerical model, but we find that the biases are moderate outside areas with tropical cyclones.

Miles' theory is unsatisfactory for the prediction of ocean wave growth under wind action. Hasselmann's nonlinear wave-wave interactions theory may offer another physical mechanism for constructing a reasonable wave prediction model. An experimental program was designed to investigate this possibility in the context of the momentum and energy transfer from wind to waves, nonlinear wave-wave interactions and white-capping dissipation. The wind field (mean velocity profiles and fluctuating pressure and velocity components) and wave field (wave height) were measured simultaneously in a fixed reference frame and as a function of fetch along the Stanford wind-wave channel under the conditions of steady wind and stationary wave spectrum. All the data were obtained 5 mm above the highest point of the wind waves for five stations (3 m apart on average) and at three wind speeds (7.09, 8.01 and 8.88 m/sec). The wave height, fluctuating pressure and velocity components were measured by a capacitance wave height gauge, a crystal pressure transducer and a cross hot film probe, respectively.

A new-generation meteor radar was installed at the Brazilian Antarctic Comandante Ferraz Base (62.1degS) in March 2010. This paper describes the motivations for the radar location, its measurement capabilities, and comparisons of measured mean winds, tides, and gravity wave momentum fluxes from April to June of 2010 and 2011 with those by a similar radar on Tierra del Fuego (53.8degS). Motivations for the radars include the "hotspot" of small-scale gravity wave activity extending from the troposphere into the mesosphere and lower thermosphere (MLT) centered over the Drake Passage, the maximum of the semidiurnal tide at these latitudes, and the lack of other MLT wind measurements in this latitude band. Mean winds are seen to be strongly modulated at planetary wave and longer periods and to exhibit strong coherence over the two radars at shorter time scales as well as systematic seasonal variations. The semidiurnal tide contribute most to the large-scale winds over both radars, with maximum tidal amplitudes during May and maxima at the highest altitudes varying from approx.20 to >70 m/s. In contrast, the diurnal tide and various planetary waves achieve maximum winds of approx.10 to 20 m/s. Monthly-mean gravity wave momentum fluxes appear to reflect the occurrence of significant sources at lower altitudes, with relatively small zonal fluxes over both radars, but with significant, and opposite, meridional momentum fluxes below approx.85 km. These suggest gravity waves propagating away from the Drake Passage at both sites, and may indicate an important source region accounting in part for this "hotspot".

Bibliography: l. 176-181

By comparing operational wind and wave models to GEOSAT, we found that on 10 March 1986, the Federal Republic of Germany had the best skill score for a regional wind analysis, NOAA had the best score for a global wind analysis, and the U.S. Navy had the best score for a global wave analysis the Netherlands had the best score for a regional wave analysis and the U.S. Navy had the best score for a global wave analysis.

By comparing operational wind and wave models to GEOSAT, we found that on 10 March 1986, the Federal Republic of Germany had the best skill score for a regional wind analysis, NOAA had the best score for a global wind analysis, and the U.S. Navy had the best score for a global wave analysis the Netherlands had the best score for a regional wave analysis and the U.S. Navy had the best score for a global wave analysis.

This report is a source document for specifying wind and wave conditions for the North Pacific Ocean. The data are derived from the U.S. Navy's Spectral Ocean Wave Model (SOWM) hindcast wind and wave climatology. Some initial efforts by the Navy to synthesize the hindcasts into design tools are presented in this report. The report provides seasonal and geographic distributions of wind and wave parameters and specifies mathematical models by which wave spectra, required by any ship seakeeping performance methodology, can be developed. Long-term extreme wave predictions for fatigue analysis are also discussed.

www.holyspiritspeaks.org/god-himself-the-unique-vii/ “Story 2. A Great Mountain, a Little Stream, a Fierce Wind, and a Gigantic Wave There was a tiny stream that meandered to and fro, finally arriving at the foot of a great mountain. The mountain was blocking the tiny stream’s path, so the stream asked the mountain in his weak, little voice, “Please let me pass, you are standing in my way and blocking my path forward.” The mountain then asked, “Where are you going?” To which the little stream responded, “I am looking for my home.” The mountain said, “Alright, go ahead and flow right over me!” But because the tiny stream was too weak and too young, there was no way for it to flow over such a large mountain, so it had no choice but to keep flowing to the foot of the mountain … A fierce wind swept by, carrying with it sand and dust to where the mountain stood. The wind bellowed at the mountain, “Let me pass!” The mountain asked, “Where are you going?” The wind howled back, “I want to go over to that side of the mountain.” The mountain said, “Alright, if you can break through my middle, then you can go!” The fierce wind howled this way and that, but no matter how furiously it blew, it couldn’t break through the middle of the mountain. The wind grew tired, and stopped to rest. So on that side of the mountain only a weak wind blew fitfully, which pleased the people there. Such was the greeting the mountain gave to the people … At the seashore, the ocean spray rolled gently against the reef. Suddenly, a gigantic wave came up and roared its way toward the mountain. “Move over!” shouted the gigantic wave. The mountain asked, “Where are you going?” The great wave did not stop, and it continued to surge as it responded, “I’m expanding my territory and I want to stretch my arms a bit.” The mountain said, “Alright, if you can pass over my peak, I’ll yield the way.” The great wave moved back a bit, and then once again surged toward the mountain. But no matter how hard it tried, it couldn’t get over the mountain. It had no choice but to slowly recede back from whence it came … Over the centuries, the tiny stream trickled gently around the foot of the mountain. By following the course the mountain had made, the tiny stream made it back to its home; it joined the river, and flowed into the sea. Under the mountain’s care, the tiny stream never became lost. The tiny stream and the great mountain relied on one another, they restrained one another, and depended on one another.” from Continuation of The Word Appears in the Flesh Source: https://www.flickr.com/photos/147974511@N04/36982415330 Uploader: Maltz Evans

www.holyspiritspeaks.org/god-himself-the-unique-vii/ "Over the centuries, the fierce wind did not change its habits of howling at the mountain. The fierce wind blew great swirls of sand when it “visited” the mountain just as it had before. It threatened the mountain, but never broke through the middle of the mountain. The fierce wind and the great mountain relied on one another, they restrained one another, and depended on one another." from Continuation of The Word Appears in the Flesh Source: https://www.flickr.com/photos/147974511@N04/38551745095 Uploader: Maltz Evans

The paper discusses the following: 1. No-cost Extension. The no-cost extension is required to complete the work on the unified model codes (both hydrodynamic and kinetic Monte Carlo) as described in the initial proposal and previous annual reports. 2. Scientific Accomplishments during the Report Period. We completed a comprehensive model of Alfvtn wave reflection that spans the full distance from the photosphere to the distant heliosphere. 3. Comparison of Accomplishments with Proposed Goals. The proposal contained two specific objectives for Year 3: (1) to complete the unified model code, and (2) to apply it to various kinds of coronal holes (and polar plumes within coronal holes). Although the anticipated route toward these two final goals has changed (see accomplishments 2a and 2b above), they remain the major milestones for the extended period of performance. Accomplishments la and IC were necessary prerequisites for the derivation of ''physically relevant transport and mode-coupling terms'' for the unified model codes (as stated in the proposal Year 3 goals). We have fulfilled the proposed ''core work'' to study 4 general types of physical processes; in previous years we studied turbulence, mode coupling (Le., non-WKB reflection), and kinetic wave damping, and accomplishment lb provides the fourth topic: nonlinear steepening.

intervention and recording made during the Sound Tectonics workshop in Athens: http://soundtectonics.com/

intervention and recording made during the Sound Tectonics workshop in Athens: http://soundtectonics.com/

The geometry for the NASA Scanning Radar Altimeter (SRA) is shown. It transmits a 8-ns duration pulse at Ka-band (8.3 mm) and measures time of flight as it scans a 1 degree (two-way) beam from left to right across the aircraft ground track. The most recent configuration determines the surface elevation at 64 points spaced at uniform angular intervals of about 0.7 across a swath whose width is about 0.8 times the aircraft altitude. The system generates these raster lines of the surface topography beneath the aircraft at about a 10 Hz rate. In postflight processing the SRA wave topographic data are transformed with a two-dimensional Fast Fourier Transformation (FFT) and Doppler corrected to produce directional wave spectra. The SRA is not absolutely calibrated in power, but by measuring the relative fall-off of backscatter with increasing incidence angle, the SRA can also determine the mean square slope (mss) of the sea surface, a surrogate for wind speed. For the slope-dependent specular point model of radar sea surface scattering, an expression approximated by a geometric optics form, for the relative variation with incidence angle of the normalized backscatter radar cross section would be sigma (sup 0) (sub rel) = sec (exp 4) theta exp (-tan squared theta/mss) where theta is the off-nadir incidence angle.

Available from National Technical Information Service, Springfield, Va