Annales Geophysicae, 2005 This study uses digital ionosonde data from a cusp latitude station (Cambridge Bay, 77° CGM lat.) to study the convection into the polar cap. Days when the IMF magnetic field was relatively steady were used. On many days it was possible to distinguish
J. MacDougall, P. T. Jayachandran
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AMPERE polar cap boundaries [PDF]
Annales Geophysicae, 2020 The high-latitude atmosphere is a dynamic region with processes that respond to forcing from the Sun, magnetosphere, neutral atmosphere, and ionosphere. Historically, the dominance of magnetosphere–ionosphere interactions has motivated upper atmospheric
A. G. Burrell +6 more
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The mechanisms of DEPDC7-mediated actin cap establishment and meiosis progression in oocytes [PDF]
EMBO ReportsAsymmetric division is crucial for oocyte and embryo development. During meiosis I, the spindle migrates to the subcortex, and F-actin accumulates to form the actin cap, which supports polar body extrusion. While the CDC42–NWASP–ARP2/3 pathway, regulated
Jian Mu +11 more
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A Case Study of Polar Cap Sporadic-E Layer Associated with TEC Variations
Remote Sensing, 2021 The Sporadic-E (Es) layer is an often-observed phenomenon at high latitudes; however, our understanding of the polar cap Es layer is severely limited due to the scarce number of measurements.
Yong Wang +6 more
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Storm time polar cap expansion: interplanetary magnetic field clock angle dependence [PDF]
Annales Geophysicae, 2023 It is well known that the polar cap, delineated by the open–closed field line boundary (OCB), responds to changes in the interplanetary magnetic field (IMF).
B. Tulegenov +6 more
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The pulsed nature of the nightside contribution to polar cap convection: repetitive substorm activity under steady interplanetary driving [PDF]
Annales Geophysicae, 2012 The aim of this study is to investigate the relative contributions of dayside and nightside processes to the spatial and temporal structure of polar cap plasma convection. The central parameter is the cross-polar cap potential (CPCP). Selecting a 10-
P. E. Sandholt +2 more
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Central polar cap convection response to short duration southward Interplanetary Magnetic Field [PDF]
Annales Geophysicae, 2000 Central polar cap convection changes associated with southward turnings of the Interplanetary Magnetic Field (IMF) are studied using a chain of Canadian Advanced Digital Ionosondes (CADI) in the northern polar cap.
P. T. Jayachandran +2 more
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Recently research advances on the polar cap patches
地球与行星物理论评, 2023 The polar cap patch is a common ionospheric structure. It often appears in the F region of the ionosphere over the polar caps; these patches are usually characterized by electron densities that can be even twice greater than that of the surrounding area.
Yong Wang +4 more
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Variations in the polar cap area during intervals of substorm activity on 20-21 March 1990 deduced from AMIE convection patterns [PDF]
Annales Geophysicae, 1996 The dynamic behaviour of the northern polar cap area is studied employing Northern Hemisphere electric potential patterns derived by the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure. The rate of change in area of the polar cap,
J. R. Taylor +4 more
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HF radar polar patch formation revisited: summer and winter variations in dayside plasma structuring [PDF]
Annales Geophysicae, 2002 Three intervals of polar patch formation, as observed by the CUTLASS Finland HF coherent radar, are presented. Simultaneous observations from a vertical ionosonde located at Longyearbyen on Svalbard, situated in the dayside convection throat region,
S. E. Milan +3 more
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