Skylab S193 and the analysis of the wind field over the ocean

The present status of the program to provide proof of concept for the idea that simultaneously observed radar scattering cross section measurements and passive microwave measurements can be used to determine the winds in the planetary boundary layer over the ocean, is given. The role of S193 in Skylab is providing the final clinching proof that an operational instrument will obtain data of great value to both meteorology and oceanography is described

Oceanographic and meteorological research based on the data products of SEASAT

Reservations were expressed concerning the sum of squares wind recovery algorithm and the power law model function. The SAS sum of squares (SOS) method for recovering winds from backscatter data leads to inconsistent results when V pol and H pol winds are compared. A model function that does not use a power law and that accounts for sea surface temperature is needed and is under study both theoretically and by means of the SASS mode 4 data. Aspects of the determination of winds by means of scatterometry and of the utilization of vector wind data for meteorological forecasts are elaborated. The operational aspect of an intermittent assimilation scheme currently utilized for the specification of the initial value field is considered with focus on quantifying the absolute 12-hour linear displacement error of the movement of low centers

Does the scatterometer see wind speed or friction velocity?

Studies of radar backscatter from the sea surface are referred either to the wind speed, U, or friction velocity, u(sub *). Bragg scattering theory suggests that these variations in backscatter are directly related to the height of the capillary-gravity waves modulated by the larger waves in tilt and by straining of the short wave field. The question then arises as to what characteristic of the wind field is most probably correlated with the wave number spectrum of the capillary-gravity waves. The justification for selecting U as the appropriate meteorological parameter to be associated with backscatter from L-band to Ku-band are reviewed. Both theoretical reasons and experimental evidence are used to demonstrate that the dominant parameter is U/C(lambda) where U is the wind speed at a height of about lambda/2 for waves having a phase speed of C(lambda)

THE LAND DIVISION AMENDMENTS TO THE SUBDIVISION CONTROL ACT

On January 21, 1997, Governor Engler signed into law 1996 P.A. 591, the Land Division Act. This Act replaced the Subdivision Control Act after 30 years and changed the rules on how land is divided in Michigan. 1997 P.A. 87, effective July 28, 1997, amended the recently created 1996 Land Division Act. While some hailed these as positive changes allowing improved land use, others strongly disagree. This paper is an attempt to alleviate the frustration by providing a history of land division legislation in Michigan because past laws creates an assumed set of rights which are not easily changes. The second focus of the paper is to lessen the confusion level by defining the main points of the law.Land Economics/Use,

Verification results for the Spectral Ocean Wave Model (SOWM) by means of significant wave height measurements made by the GEOS-3 spacecraft

Significant wave heights estimated from the shape of the return pulse wave form of the altimeter on GEOS-3 for forty-four orbit segments obtained during 1975 and 1976 are compared with the significant wave heights specified by the spectral ocean wave model (SOWM), which is the presently operational numerical wave forecasting model at the Fleet Numerical Weather Central. Except for a number of orbit segments with poor agreement and larger errors, the SOWM specifications tended to be biased from 0.5 to 1.0 meters too low and to have RMS errors of 1.0 to 1.4 meters. The much fewer larger errors can be attributed to poor wind data for some parts of the Northern Hemisphere oceans. The bias can be attributed to the somewhat too light winds used to generate the waves in the model. Other sources of error are identified in the equatorial and trade wind areas

Real-time antenna fault diagnosis experiments at DSS 13

Experimental results obtained when a previously described fault diagnosis system was run online in real time at the 34-m beam waveguide antenna at Deep Space Station (DSS) 13 are described. Experimental conditions and the quality of results are described. A neural network model and a maximum-likelihood Gaussian classifier are compared with and without a Markov component to model temporal context. At the rate of a state update every 6.4 seconds, over a period of roughly 1 hour, the neural-Markov system had zero errors (incorrect state estimates) while monitoring both faulty and normal operations. The overall results indicate that the neural-Markov combination is the most accurate model and has significant practical potential

The extrapolation of laboratory and aircraft radar sea return data to spacecraft altitudes

Laboratory measurements show that the spectra of capillary waves grow with wind speed over six orders of magnitude. The scatter in the data can be partially understood and predicted from a combination of turbulence theory, radar theory, and the small sample theory of statistical inference. When these results are applied to a prediction of the sea return values to be obtained by S193 on Skylab, it can be shown that the size of the illuminated patch effectively averages out the horizontal scales of gustiness, so that the measurement will correspond to the synoptic scale wind

Renormalization Group Study of the Intrinsic Finite Size Effect in 2D Superconductors

Vortices in a thin-film superconductor interact logarithmically out to a distance on the order of the two-dimensional (2D) magnetic penetration depth $\lambda_\perp$, at which point the interaction approaches a constant. Thus, because of the finite $\lambda_\perp$, the system exhibits what amounts to an {\it intrinsic} finite size effect. It is not described by the 2D Coulomb gas but rather by the 2D Yukawa gas (2DYG). To study the critical behavior of the 2DYG, we map the 2DYG to the massive sine-Gordon model and then perform a renormalization group study to derive the recursion relations and to verify that $\lambda_\perp$ is a relevant parameter. We solve the recursion relations to study important physical quantities for this system including the renormalized stiffness constant and the correlation length. We also address the effect of current on this system to explain why finite size effects are not more prevalent in experiments given that the 2D magnetic penetration depth is a relevant parameter.Comment: 8 pages inRevTex, 5 embedded EPS figure

The elevation, slope, and curvature spectra of a wind roughened sea surface

The elevation, slope and curvature spectra are defined as a function of wave number and depend on the friction velocity. There are five wave number ranges of definition called the gravity wave-gravity equilibrium range, the isotropic turbulence range, the connecting range due to Leykin Rosenberg, the capillary range, and the viscous cutoff range. The higher wave number ranges are strongly wind speed dependent, and there is no equilibrium (or saturated) capillary range, at least for winds up to 30 meters/sec. Some properties of the angular variation of the spectra are also found. For high wave numbers, especially in the capillary range, the results are shown to be consistent with the Rayleigh-Rice backscattering theory (Bragg scattering), and certain properties of the angular variation are deduced from backscatter measurements

Vector wind, horizontal divergence, wind stress and wind stress curl from SEASAT-SASS at one degree resolution

Conventional data obtained in 1983 are contrasted with SEASAT-A scatterometer and scanning multichannel microwave radiometer (SMMR) data to show how observations at a single station can be extended to an area of about 150,000 square km by means of remotely sensed data obtained in nine minutes. Superobservations at a one degree resolution for the vector winds were estimated along with their standard deviations. From these superobservations, the horizontal divergence, vector wind stress, and the curl of the wind stress can be found. Weather forecasting theory is discussed and meteorological charts of the North Pacific Ocean are presented. Synoptic meteorology as a technique is examined