Interpretation of gravity wave signatures in GPS radio occultations

Mostrar todas las versiones(3)

The horizontal averaging of global positioning system radio occultation retrievals produces an amplitude attenuation and phase shift in any plane gravity wave, which may lead to significant discrepancies with respect to the original values. In addition, wavelengths cannot be straightforwardly inferr...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Alexander, P., de la Torre, A., Llamedo, P.
Formato: Artículo publishedVersion
Publicado: 2008
Materias:
Computer simulation
Global positioning system
Gravity waves
Radio waves
Wavefronts
amplitude
computer simulation
GPS
gravity wave
refractive index
spherical harmonics
wavelength
numerical model
variance analysis
wave propagation
Hydrodynamics
Waves
Analytical expressions
Delta functions
Geometrical relations
High probability
Line of Sight
Numerical simulation
Radio occultations
Relative orientation
Spherical symmetry
Wave amplitudes
Wave phase
Wave vector
Gravitational effects
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_01480227_v113_n16_p_Alexander
https://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=artiaex&d=paper_01480227_v113_n16_p_Alexander_oai
Aporte de:
Repositorio Digital de la Universidad de Buenos Aires (UBA) de Universidad de Buenos Aires
id I28-R145-paper_01480227_v113_n16_p_Alexander_oai
record_format dspace
spelling I28-R145-paper_01480227_v113_n16_p_Alexander_oai2024-08-16 Alexander, P. de la Torre, A. Llamedo, P. 2008 The horizontal averaging of global positioning system radio occultation retrievals produces an amplitude attenuation and phase shift in any plane gravity wave, which may lead to significant discrepancies with respect to the original values. In addition, wavelengths cannot be straightforwardly inferred due to the observational characteristics. If the waves produce small departures from spherical symmetry in the background atmosphere and under the assumption that the refractivity kernel may be represented by a delta function, an analytical expression may be derived in order to find how the retrieved amplitudes become weakened (against the original ones). In Particular, we study the range of waves that may be detected and the consequent reduction in variance calculation, which is found to be around 19%. A larger discrepancy was obtained when comparing an occultation variance with the one computed from a numerical simulation of that case. Wave amplitudes can be better resolved when the fronts are nearly horizontal or when the angle between the occultation line of sight and the horizontal component of the wave vector approaches π/2. Short horizontal scale waves have a high probability of becoming attenuated or of not being detected at all. We then find geometrical relations in terms of the relative orientation between waves and sounding, so, as to appropriately interpret wavelengths extracted from the acquired data. Only inertio-gravity waves, which exhibit nearly horizontal fronts, will show small differences between detected and original vertical wavelengths. Last, we analyze the retrieval effect on wave phase and find a shift between original and detected wave that generally is nonzero and approaches π /4 for the largest horizontal wavelengths. Copyright 2008 by the American Geophysical Union. Fil:Alexander, P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:de la Torre, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Llamedo, P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. application/pdf http://hdl.handle.net/20.500.12110/paper_01480227_v113_n16_p_Alexander info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar J. Geophys. Res. D Atmos. 2008;113(16) Computer simulation Global positioning system Gravity waves Radio waves Wavefronts amplitude computer simulation GPS gravity wave refractive index spherical harmonics wavelength numerical model variance analysis wave propagation Computer simulation Global positioning system Gravity waves Hydrodynamics Waves Analytical expressions Delta functions Geometrical relations High probability Line of Sight Numerical simulation Radio occultations Relative orientation Spherical symmetry Wave amplitudes Wave phase Wave vector Gravitational effects Interpretation of gravity wave signatures in GPS radio occultations info:eu-repo/semantics/article info:ar-repo/semantics/artículo info:eu-repo/semantics/publishedVersion https://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=artiaex&d=paper_01480227_v113_n16_p_Alexander_oai
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-145
collection Repositorio Digital de la Universidad de Buenos Aires (UBA)
topic Computer simulation
Global positioning system
Gravity waves
Radio waves
Wavefronts
amplitude
computer simulation
GPS
gravity wave
refractive index
spherical harmonics
wavelength
numerical model
variance analysis
wave propagation
Computer simulation
Global positioning system
Gravity waves
Hydrodynamics
Waves
Analytical expressions
Delta functions
Geometrical relations
High probability
Line of Sight
Numerical simulation
Radio occultations
Relative orientation
Spherical symmetry
Wave amplitudes
Wave phase
Wave vector
Gravitational effects
spellingShingle Computer simulation
Global positioning system
Gravity waves
Radio waves
Wavefronts
amplitude
computer simulation
GPS
gravity wave
refractive index
spherical harmonics
wavelength
numerical model
variance analysis
wave propagation
Computer simulation
Global positioning system
Gravity waves
Hydrodynamics
Waves
Analytical expressions
Delta functions
Geometrical relations
High probability
Line of Sight
Numerical simulation
Radio occultations
Relative orientation
Spherical symmetry
Wave amplitudes
Wave phase
Wave vector
Gravitational effects
Alexander, P.
de la Torre, A.
Llamedo, P.
Interpretation of gravity wave signatures in GPS radio occultations
topic_facet Computer simulation
Global positioning system
Gravity waves
Radio waves
Wavefronts
amplitude
computer simulation
GPS
gravity wave
refractive index
spherical harmonics
wavelength
numerical model
variance analysis
wave propagation
Computer simulation
Global positioning system
Gravity waves
Hydrodynamics
Waves
Analytical expressions
Delta functions
Geometrical relations
High probability
Line of Sight
Numerical simulation
Radio occultations
Relative orientation
Spherical symmetry
Wave amplitudes
Wave phase
Wave vector
Gravitational effects
description The horizontal averaging of global positioning system radio occultation retrievals produces an amplitude attenuation and phase shift in any plane gravity wave, which may lead to significant discrepancies with respect to the original values. In addition, wavelengths cannot be straightforwardly inferred due to the observational characteristics. If the waves produce small departures from spherical symmetry in the background atmosphere and under the assumption that the refractivity kernel may be represented by a delta function, an analytical expression may be derived in order to find how the retrieved amplitudes become weakened (against the original ones). In Particular, we study the range of waves that may be detected and the consequent reduction in variance calculation, which is found to be around 19%. A larger discrepancy was obtained when comparing an occultation variance with the one computed from a numerical simulation of that case. Wave amplitudes can be better resolved when the fronts are nearly horizontal or when the angle between the occultation line of sight and the horizontal component of the wave vector approaches π/2. Short horizontal scale waves have a high probability of becoming attenuated or of not being detected at all. We then find geometrical relations in terms of the relative orientation between waves and sounding, so, as to appropriately interpret wavelengths extracted from the acquired data. Only inertio-gravity waves, which exhibit nearly horizontal fronts, will show small differences between detected and original vertical wavelengths. Last, we analyze the retrieval effect on wave phase and find a shift between original and detected wave that generally is nonzero and approaches π /4 for the largest horizontal wavelengths. Copyright 2008 by the American Geophysical Union.
format Artículo
Artículo
publishedVersion
author Alexander, P.
de la Torre, A.
Llamedo, P.
author_facet Alexander, P.
de la Torre, A.
Llamedo, P.
author_sort Alexander, P.
title Interpretation of gravity wave signatures in GPS radio occultations
title_short Interpretation of gravity wave signatures in GPS radio occultations
title_full Interpretation of gravity wave signatures in GPS radio occultations
title_fullStr Interpretation of gravity wave signatures in GPS radio occultations
title_full_unstemmed Interpretation of gravity wave signatures in GPS radio occultations
title_sort interpretation of gravity wave signatures in gps radio occultations
publishDate 2008
url http://hdl.handle.net/20.500.12110/paper_01480227_v113_n16_p_Alexander
https://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=artiaex&d=paper_01480227_v113_n16_p_Alexander_oai
work_keys_str_mv AT alexanderp interpretationofgravitywavesignaturesingpsradiooccultations
AT delatorrea interpretationofgravitywavesignaturesingpsradiooccultations
AT llamedop interpretationofgravitywavesignaturesingpsradiooccultations
_version_ 1809356994620948480

Ejemplares similares