Conceptual Model of the Earth’s Global Electric Field
Maxwell’s Equations
Conceptual Model of the Earth’s Global Electric Field
Earth’s Magnetic Field
The Ionosphere
There are enough ions and electrons to make the atmosphere a reasonably good conductor Charged particles are created when solar radiation at wavelengths shorter than nm is absorbed (photoionization)
The Ionosphere: The D-layer Most of the shorter uv rays have been absorbed in E and F Longer wavelengths ( <111.8nm), x-rays and solar cosmic rays are primarily responsible Disappears at night
The Ionosphere: The E-layer A Chapman layer – The production of ions in a given region is proportional to flux of radiation and to the number of molecules in that region – Two opposing tendencies Flux diminishes Number density increases Ionization of O 2 and N 2 Transition occurs from well mixed
The Ionosphere: The F-layer F1: Chapman layer – Ionization of O (i.e. atomic oxygen) at even shorter wavelengths ( <91.1nm) – O + reacts with O 2 and N 2 to create ionized molecules F2: modified Chapman Layer – Ionization of O (i.e. atomic oxygen) at still shorter wavelengths ( <80nm) – Also some ionization of N 2
The losses We are “creating” all of these charges, where does it go? D-region: electron capture by positively charged ions E-region: dissociative recombination of a molecule that reacts with an electron F-regions: dissociative recombination of a molecule that reacts with an electron – The difference in F1 and F2 is the reaction rate differs
Ionosphere electron desnisty