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Geomagnetic Field Model Indicates Shrinking Northern Auroral Oval
(Blackwell Publishing Ltd, 2020-08)
Polar cap and auroral oval areas are presented for the period 1900‐2015 using a model of the magnetosphere and the IGRF‐12 model for the geomagnetic field. The effect of the main field long‐term changes is addressed ...
Secular variation in the composition of Brazilian mafic dyke swarms: preliminary resultsSecular variation in the composition of Brazilian mafic dyke swarms: preliminary results
(Universidade de São Paulo, Instituto de Geociências, 1989)
Equatorial E region electric fields at the dip equator: 2. Seasonal variabilities and effects over Brazil due to the secular variation of the magnetic equator
(American Geophysical Union, 2016-09-23)
In this work, the seasonal dependency of the E region electric field (EEF) at the dip equator is examined. The eastward zonal (Ey) and the daytime vertical (Ez) electric fields are responsible for the overall phenomenology ...
Geomagnetic secular variations over the last 6500 years as recorded by sediments from the lakes of south Argentina
(Wiley Blackwell Publishing, Inc, 2000-12)
Regional type curves depicting secular variations in declination and inclination through the last 6700 calendar years constructed for southwestern Argentina (about 41°S, 71°30′W) by stacking palaeomagnetic data derived ...
FoF2 long-term trend linked to Earth's magnetic field secular variation at a station under the northern crest of the equatorial ionization anomaly
(American Geophysical Union, 2016-01)
Long-term trend of the critical frequency of the F2 ionospheric region, foF2, at Phu Thuy station (21.03°N, 105.96°E), Vietnam, located under the northern crest of the equatorial ionization anomaly, EIA, is studied. Annual ...
Spatial features of geomagnetic cutoff rigidity secular variation using analytical approaches
(Elsevier, 2020-12)
The secular variation spatial pattern of geomagnetic cutoff rigidity, Rc, is analyzed considering analytical expressions. Störmer analytic Rc equation in terms of geomagnetic latitude is used considering a pure dipolar ...
A full-vector paleomagnetic secular variation record from 55,000 to 33,000 cal. years BP from Río Valdéz glaciolacustrine outcrop (Tierra Del Fuego, Argentina)
(Elsevier Science, 2021-07)
High-resolution paleomagnetic investigations were performed on Río Valdez outcrop at the Fagnano Lake, central Isla Grande de Tierra del Fuego, southernmost South America. Our aims were to develop a full-vector paleomagnetic ...