Some studies on the propagation of long distant VLF IF natural and transmitted signals in relation to climatic and geophysical events

Abstract

In the last few decades several research activities are taking place round the globe for under standing the perturbations produced in the lower region of the ionosphere due to several Solar and Geophysical factors like; Solar Flare, Solar Coronal Mass Ejection (CME), Sunspotactivity, Geomagnetic Storm, Earthquake, Meteor shower, Solar Eclipse, etc. The lower region of the Ionosphere is thought to be coupled with lithosphere and atmosphere by the help of a Global Electrical Circuit (GEC). The research work is an effort to understand the perturbations caused from lithosphere to atmosphere and then to ionosphere, by the help of studies on earthquakes, Earth s vertical electric field, geomagnetic storms and meteor showers. The significance of the receiver location (North East India) is also strategically important which is located in the foothill of the Himalayas and close to Bay of Bengal. It is also closely situated to the region of highest rainfall in the world, Cherrapunji and also situated in the most earthquake prone zone 5. Thus it is an ideal place on Earth to make such kind of studies.