scholarly journals The ionospheric response to interplanetary magnetic field variations: Evidence for rapid global change and the role of preconditioning in the magnetosphere

2000 ◽  
Vol 105 (A10) ◽  
pp. 22955-22977 ◽  
Author(s):  
Masakazu Watanabe ◽  
Natsuo Sato ◽  
Raymond A. Greenwald ◽  
Michael Pinnock ◽  
Marc R. Hairston ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Global Change ◽  
Interplanetary Magnetic Field ◽  
Ionospheric Response ◽  
Magnetic Field Variations

Comparison of polar ionospheric behavior at Arctic and Antarctic regions for improved satellite-based positioning

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Arun Kumar Singh ◽  
Sampad Kumar Panda
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Arctic Region ◽  
Auroral Oval ◽  
Ionospheric Scintillation ◽  
Electron Content ◽  
Total Electron ◽  
Polar Latitude ◽  
Tec Variability

Abstract In this paper, we investigate the hemispheric symmetric and asymmetric characteristics of ionospheric total electron content (TEC) and its dependency on the interplanetary magnetic field (IMF) in the northern and southern polar ionosphere. The changes in amplitude and phase scintillation are also probed through Global Ionospheric Scintillation and TEC monitoring (GISTM) systems recordings at North pole [Himadri station; Geographic 78°55′ N, 11°56′ E] and South pole [Maitri station; Geographic 70°46′ S 11°44′ E]. Observations show the range of %TEC variability being relatively more over Antarctic region (−40 % to 60 %) than Arctic region (−25 % to 25 %), corroborating the role of the dominant solar photoionization production process. Our analysis confirms that TEC variation at polar latitudes is a function of magnetosphere-ionosphere coupling, depending on interplanetary magnetic field (IMF) orientation and magnitude in the X ( B x Bx ), Y ( B y By ), and Z ( B z Bz ) plane. Visible enhancement in TEC is noticed in the northern polar latitude when B x < 0 Bx<0 , B y < − 6 nT By<-6\hspace{0.1667em}\text{nT} or B y > 6 nT By>6\hspace{0.1667em}\text{nT} and B z > 0 Bz>0 whereas the southern polar latitude perceives TEC enhancements with B x > 0 Bx>0 , − 6 nT < B y < 6 nT -6\hspace{0.1667em}\text{nT}<By<6\hspace{0.1667em}\text{nT} and B z < 0 Bz<0 . Further investigation reveals the intensity of phase scintillation being more pronounced than the amplitude scintillation during the disturbed geomagnetic conditions with excellent correlation with the temporal variation of TEC at both the stations. Corresponding variations in the parameters are studied in terms of particle precipitation, auroral oval expansion, Joule’s heating phenomena, and other ionospheric parameters. The studies are in line with efforts for improving ionospheric delay error and scintillation modeling and satellite-based positioning accuracies in polar latitudes.

Cosmic ray north-south anisotropy: The role of the interplanetary magnetic field

1982 ◽  
Vol 87 (A12) ◽  
pp. 10325 ◽  
Author(s):  
M. A. Pomerantz ◽  
S. P. Duggal ◽  
A. J. Owens ◽  
M. F. Tolba ◽  
C. H. Tsao
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Cosmic Ray

scholarly journals Ionospheric response to the interplanetary magnetic field southward turning: Fast onset and slow reconfiguration

2002 ◽  
Vol 107 (A8) ◽  
pp. SIA 2-1-SIA 2-9 ◽  
Author(s):  
G. Lu ◽  
T. E. Holzer ◽  
D. Lummerzheim ◽  
J. M. Ruohoniemi ◽  
P. Stauning ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Ionospheric Response ◽  
Fast Onset

scholarly journals Dayside ionospheric response to changes in IMF polarity: optical and plasma-flow observations

2000 ◽  
Vol 18 (7) ◽  
pp. 782-788 ◽  
Author(s):  
S. E. Pryse ◽  
A. M. Smith ◽  
L. Kersley
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Plasma Flow ◽  
Line Emission ◽  
Line Of Sight ◽  
Magnetospheric Physics ◽  
Polar Cap ◽  
Ionospheric Response ◽  
Present Case Study

Abstract. The response of the dayside ionosphere to changes in polarity of the interplanetary magnetic field was observed by two independent techniques. The signatures were seen in the 630.0 nm red-line emission, measured by a meridian scanning photometer at Ny-Ålesund on Svalbard, and also in the line-of-sight plasma velocities monitored by the Finland CUTLASS SuperDARN radar. A time difference of some 6 to 8 min occurred between the responses of the two techniques, with the flows being first to respond. In the present case study, the longer delay in the optics suggests that ion precipitation controls the auroral emission.Key words: Ionosphere (ionosphere-magnetosphere interactions) · Magnetospheric physics (magnetosphere-ionosphere interactions; polar cap phenomena)

scholarly journals Interhemispheric observations of the ionospheric signature of tail reconnection during IMF-northward non-substorm intervals

2005 ◽  
Vol 23 (5) ◽  
pp. 1763-1770 ◽  
Author(s):  
A. Grocott ◽  
T. K. Yeoman ◽  
S. E. Milan ◽  
S. W. H. Cowley
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Field Data ◽  
Plasma Convection ◽  
Field Orientation ◽  
Magnetic Field Data ◽  
Ionospheric Response ◽  
Ionosphere Plasma ◽  
Dayside Magnetopause ◽  
Geosynchronous Satellites

Abstract. This paper presents the first interhemispheric radar observations interpreted as the ionospheric response to tail reconnection during IMF-northward non-substorm intervals. SuperDARN measurements of plasma convection in the nightside ionospheres of both hemispheres, taken on 21–22 February and 26–27 April 2000, show bursts of flow in the midnight sector which are understood to be characteristic of such phenomena. Upstream interplanetary magnetic field data confirm that the field orientation at the dayside magnetopause was northwards, but with a significant IMF By component (negative during the first interval, positive during the second), for many hours prior to the bursts being observed. During the By-negative interval the bursts were directed westwards in the Northern Hemisphere and eastwards in the Southern Hemisphere; during the By-positive interval their directions were reversed. These two asymmetries between the different orientations of IMF By and between the two hemispheres are key to our understanding of the magnetospheric phenomenon responsible for generating the bursts. They provide further evidence in support of the idea that the bursts are a result of reconnection in an asymmetric tail under the prolonged influence of IMF By. Concurrent data from ground magnetometers and geosynchronous satellites confirm that the bursts have no associated substorm characteristics, consistent with previous studies. Keywords. Ionosphere (Plasma convection; Ionospheremagnetosphere interactions) – Magnetospheric Physics (Magnetotail)

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