International geomagnetic reference field: The third generation.

Peddie, Norman W.

doi:10.5636/jgg.34.309

Cited by 132 publications

(39 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Two computer models are employed in this work: the International Geomagnetic Reference Field (IGRF) [Peddie, 1982] …”

Section: General Results Of Simulationsmentioning

confidence: 99%

Interhemispheric propagation of VLF transmissions in the presence of ionospheric HF heating

Starks¹,

Lee²,

Jastrzębski³

2001

J. Geophys. Res.

View full text Add to dashboard Cite

Abstract. Recent experiments carried out at the Arecibo Observatory in Puerto Rico and the magnetically conjugate location in Argentina suggest a connection between the prevalence and intensity of the interhemispheric propagation of VLF transmissions and HF heating of the ionosphere. During several nights of the study the O-mode CW heater appeared to enhance the coupling of VLF transmissions into the affected region of plasma. These signals presumably then entered plasmaspheric ducts more efficiently and led to conjugate measurements of relatively high amplitude. No such effects were seen with pulsed or X-mode heating. Short time resolution measurements of fading transmissions were marked by transit delays and amplitudes that remained nearly constant as the interhemispheric VLF signals diminished, consistent with the model of a plasmaspheric duct complemented by favorable plasma structures extending well into the F region but producing the majority of the total transit delay at plasmaspheric altitudes. It is also suggested that weak long-delay receptions often observed in these data are most probably prolongitudinal whistlers that are not ducted but which represent a potential contaminant in ducted VLF experiments of all types.

show abstract

“…Two computer models are employed in this work: the International Geomagnetic Reference Field (IGRF) [Peddie, 1982] …”

Section: General Results Of Simulationsmentioning

confidence: 99%

Interhemispheric propagation of VLF transmissions in the presence of ionospheric HF heating

Starks¹,

Lee²,

Jastrzębski³

2001

J. Geophys. Res.

View full text Add to dashboard Cite

show abstract

“…The aeromagnetic data were reprocessed for purposes of incorporating a more accurate geomagnetic reference field, identifying errors in flight-line locations, and smoothing the effects of these location errors. The total-intensity magnetic data were gridded by means of a minimum-curvature algorithm (Briggs, 1974;Webring, 1981), reduced by subtracting a gridded Definitive Geomagnetic Reference Field (DGRF) updated to the time of the survey (Peddie, 1982; International Association of Geomagnetism and Aeronomy (IAGA) Division I, Working Group I, 1986), and contoured by means of an algorithm for splining under tension (Cline, 1974;Evenden, 1975;Godson and Webring, 1982). The resulting contour map displayed large errors, presumably associated with mislocations of flight lines, which were manifested by linear anomalies along flight lines and inconsistent anomaly patterns where flight lines crossed tie lines.…”

Section: Geophysics Methodsmentioning

confidence: 99%

Mineral resources of the Harquahala Mountains Wilderness Study Area, La Paz and Maricopa counties, Arizona

DeWitt¹,

Richard²,

Hassemer³

et al. 1988

View full text Add to dashboard Cite

“…For example, precise knowledge of the geomagnetic field is important in detailed studies of: (i) the motion of trapped particles that form the ''Van Allen radiation belts'' (Roederer, 1972;Walt, 1994); (ii) the precipitation of auroral particles into the upper atmosphere (McIlwain, 1960;Albert, 1967;Evans, 1968;Eather, 1973;Meng, 1978;Feldstein and Galperin, 1985;Gorney, 1987;Newell et al, 1991); and (iii) the trajectories of energetic solar protons and galactic cosmic rays in the vicinity of the Earth (St ormer, 1955;Vallarta, 1961;Alfv en and F althammar, 1963;Northrop, 1963;Roederer, 1970;Baker et al, 1990;Shea and Smart, 1990). In many branches of solar-terrestrial physics, the International Geomagnetic Reference Field (IGRF), or Definitive Geomagnetic Reference Field (DGRF), which specifies the (external) magnetic field originating from electric currents within the interior of the Earth (Peddie, 1982;Langel, 1992), provides a fundamental magnetic reference system (Hultqvist, 1958, McIlwain, 1961Hakura, 1965;Gustafsson, 1970Gustafsson, , 1984Stassinopoulos et al, 1984;Baker and Wing, 1989;Gustafsson et al, 1992;Papitashvili et al, 1992). This reference magnetic field is also used extensively in the analysis and interpretation of ionospheric plasma velocities measured by both coherentand incoherent-scatter radars (Greenwald et al, 1978;Nielson et al, 1983;Rishbeth and Williams, 1985;.…”

Section: Introductionmentioning

confidence: 99%

Uncertainties in field-line tracing in the magnetosphere. Part I: the axisymmetric part of the internal geomagnetic field

1997

View full text Add to dashboard Cite

Abstract.The technique of tracing along magnetic field lines is widely used in magnetospheric physics to provide a ''magnetic frame of reference'' that facilitates both the planning of experiments and the interpretation of observations. The precision of any such magnetic frame of reference depends critically on the accurate representation of the various sources of magnetic field in the magnetosphere. In order to consider this important problem systematically, a study is initiated to estimate first the uncertainties in magnetic-field-line tracing in the magnetosphere that arise solely from the published (standard) errors in the specification of the geomagnetic field of internal origin. Because of the complexity in computing these uncertainties for the complete geomagnetic field of internal origin, attention is focused in this preliminary paper on the uncertainties in magnetic-fieldline tracing that result from the standard errors in just the axisymmetric part of the internal geomagnetic field. An exact analytic equation exists for the magnetic field lines of an arbitrary linear combination of axisymmetric multipoles. This equation is used to derive numerical estimates of the uncertainties in magnetic-field-line tracing that are due to the published standard errors in the axisymmetric spherical harmonic coefficients (i.e. g 0 n 6 g 0 n ). Numerical results determined from the analytic equation are compared with computational results based on stepwise numerical integration along magnetic field lines. Excellent agreement is obtained between the analytical and computational methods in the axisymmetric case, which provides great confidence in the accuracy of the computer program used for stepwise numerical integration along magnetic field lines. This computer program is then used in the following paper to estimate the uncertainties in magnetic-field-line tracing in the magnetosphere that arise from the published standard errors in the full set of spherical harmonic coefficients, which define the complete (non-axisymmetric) geomagnetic field of internal origin. Numerical estimates of the uncertainties in magnetic-field-line tracing in the magnetosphere, calculated here for the axisymmetric part of the internal geomagnetic field, should be regarded as ''first approximations'' in the sense that such estimates are only as accurate as the published standard errors in the set of axisymmetric spherical harmonic coefficients. However, all procedures developed in this preliminary paper can be applied to the derivation of more realistic estimates of the uncertainties in magnetic-field-line tracing in the magnetosphere, following further progress in the determination of more accurate standard errors in the spherical harmonic coefficients.

show abstract

International geomagnetic reference field: The third generation.

Cited by 132 publications

References 11 publications

Interhemispheric propagation of VLF transmissions in the presence of ionospheric HF heating

Interhemispheric propagation of VLF transmissions in the presence of ionospheric HF heating

Mineral resources of the Harquahala Mountains Wilderness Study Area, La Paz and Maricopa counties, Arizona

Uncertainties in field-line tracing in the magnetosphere. Part I: the axisymmetric part of the internal geomagnetic field

Contact Info

Product

Resources

About