The SeaSat-A satellite scatterometer

Grantham, W. D.; Bracalente, E. M.; Jones, W. Linwood; Johnson, James W.

doi:10.1109/joe.1977.1145338

Cited by 69 publications

(13 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…NSCAT is one of a series of spaceborne scatterometers beginning with the Skylab mission and Seasat A in the 1970s [Grantham et al, 1977] Two principal validation approaches are used in this study. First, collocation statistics are used to compare the NSCAT winds to surface winds from other sources, including wind observations and meteorological analyses.…”

Section: Paper Number 98jc02374mentioning

confidence: 99%

See 1 more Smart Citation

Geophysical validation of NSCAT winds using atmospheric data and analyses

Atlas¹,

Bloom²,

Hoffman³

et al. 1999

J. Geophys. Res.

View full text Add to dashboard Cite

Abstract. A detailed geophysical evaluation of the initial NASA scatterometer (NSCAT) wind data sets was performed in order to determine the error characteristics of these data and their applicability to ocean surface analysis and numerical prediction. The first component of this evaluation consisted of collocations of NSCAT data to ship and buoy wind reports, special sensor microwave imager wind observations, and National Centers for Environmental Prediction and Goddard Earth Observing System (GEOS) model wind analyses. This was followed by data assimilation experiments to determine the impact of NSCAT data on analysis and forecasting. The collocation comparisons showed the NSCAT wind velocity data to be of higher accuracy than operational ERS 2 wind data. The impact experiments showed that NSCAT has the ability to correct major errors in analyses over the oceans and also to improve numerical weather prediction. NSCAT data typically show the precise locations of both synoptic-scale and smaller-scale cyclones and fronts over the oceans. This often results in significant improvements to analyses. Forecast experiments using the GEOS model show approximately a 1-day extension of useful forecast skill in the southern hemisphere, in good agreement with the results of Observing System Simulation Experiments conducted prior to launch. IntroductionOcean surface winds are the most important factor coupling the ocean and atmosphere. Surface winds control the fluxes of momentum, heat, and moisture at the atmosphere-ocean interface. They are key to the scientific understanding of climate and to operational forecasting at the long range (1 month to 1 year). Surface wind data are also needed for nowcasting conditions at sea, for wave forecasting, for providing boundary conditions for ocean general circulation models, and for refining the analyses of ocean surface wind which are part of the initial conditions for numerical weather prediction (NWP).The ocean is vast; ships and buoys are few and irregularly located. Satellite microwave remote sensing of the ocean surface now provides a complete and accurate depiction of the surface wind over the ocean. The focus of this paper is the validation of the wind vectors observed by the NASA scatterometer (

show abstract

Section: Paper Number 98jc02374mentioning

confidence: 99%

“…NSCAT is one of a series of spaceborne scatterometers beginning with the Skylab mission and Seasat A in the 1970s [Grantham et al, 1977] and continuing in the 1990s with the European Remote Sensing missions, ERS 1 and ERS 2 [Francis et al, 1991]. Future NASA missions include QUIKSCAT (QSCAT) and Sea Winds.…”

Section: Introductionmentioning

confidence: 99%

Geophysical validation of NSCAT winds using atmospheric data and analyses

Atlas¹,

Bloom²,

Hoffman³

et al. 1999

J. Geophys. Res.

View full text Add to dashboard Cite

show abstract

“…There are two approaches to the wind speed measurements by SAR. The first approach utilizes the standard algorithm based on the empirical geophysical model function (GMF) used in the microwave wind scatterometers [8,[386][387][388][389]. There are well-defined GMFs at Ku-band to L-band, in particular, the Ku-and C-band GMFs are very accurate for the reasons that these bands are generally used for wind scatterometers [390].…”

Section: Ocean Windsmentioning

confidence: 99%

Recent Trend and Advance of Synthetic Aperture Radar with Selected Topics

2013

View full text Add to dashboard Cite

The present article is an introductory paper in this special issue on synthetic aperture radar (SAR). A short review is presented on the recent trend and development of SAR and related techniques with selected topics, including the fields of applications, specifications of airborne and spaceborne SARs, and information contents in and interpretations of amplitude data, interferometric SAR (InSAR) data, and polarimetric SAR (PolSAR) data. The review is by no means extensive, and as such only brief summaries of of each selected topics and key references are provided. For further details, the readers are recommended to read the literature given in the references theirin.

show abstract

“…The Seasat-A Satellite Scatterometer operated from June to October 1978 and proved that accurate wind velocity, wave heights, sea ice features and ocean topography measurements could be made from space. [6] Of course, all this remains at a greater scale compare to semiconductor metrology, but the measure and the solving of the parametric problem work on the same principle. Scatterometry is an indirect measurement method, where dimensions, geometry and material indices of the structures under test are reconstructed from the measured scatterograms applying inverse rigorous calculations either by nonlinear optimization or by comparison with relatively large previously computed data bases.…”

Section: Scatterometry First Steps…mentioning

confidence: 99%

S-Genius, a universal software platform with versatile inverse problem resolution for scatterometry

et al. 2013

View full text Add to dashboard Cite

S-Genius is a new universal scatterometry platform, which gathers all the LTM-CNRS know-how regarding the rigorous electromagnetic computation and several inverse problem solver solutions. This software platform is built to be a userfriendly, light, swift, accurate, user-oriented scatterometry tool, compatible with any ellipsometric measurements to fit and any types of pattern. It aims to combine a set of inverse problem solver capabilities -via adapted LevenbergMarquard optimization, Kriging, Neural Network solutions -that greatly improve the reliability and the velocity of the solution determination. Furthermore, as the model solution is mainly vulnerable to materials optical properties, S-Genius may be coupled with an innovative material refractive indices determination. This paper will a little bit more focuses on the modified Levenberg-Marquardt optimization, one of the indirect method solver built up in parallel with the total SGenius software coding by yours truly. This modified Levenberg-Marquardt optimization corresponds to a Newton algorithm with an adapted damping parameter regarding the definition domains of the optimized parameters. Currently, S-Genius is technically ready for scientific collaboration, python-powered, multi-platform (windows/linux/macOS), multi-core, ready for 2D-(infinite features along the direction perpendicular to the incident plane), conical, and 3D-features computation, compatible with all kinds of input data from any possible ellipsometers (angle or wavelength resolved) or reflectometers, and widely used in our laboratory for resist trimming studies, etching features characterization (such as complex stack) or nano-imprint lithography measurements for instance. The work about kriging solver, neural network solver and material refractive indices determination is done (or about to) by other LTM members and about to be integrated on S-Genius platform.

show abstract

The SeaSat-A satellite scatterometer

Cited by 69 publications

References 8 publications

Geophysical validation of NSCAT winds using atmospheric data and analyses

Geophysical validation of NSCAT winds using atmospheric data and analyses

Recent Trend and Advance of Synthetic Aperture Radar with Selected Topics

S-Genius, a universal software platform with versatile inverse problem resolution for scatterometry

Contact Info

Product

Resources

About