Conceptual Model of the Earth’s Global Electric Field

1. Conceptual Model of the Earth’s Global Electric Field

3. Maxwell’s Equations

4. Conceptual Model of the Earth’s Global Electric Field

5. Earth’s Magnetic Field

6. Earth’s Magnetic Field

7. The Ionosphere

8. 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 102.7 nm is absorbed (photoionization)

9. The Ionosphere: The D-layer • Most of the shorter uv rays have been absorbed in E and F • Longer wavelengths (l<111.8nm), x-rays and solar cosmic rays are primarily responsible • Disappears at night

10. 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 O2 and N2 • Transition occurs from well mixed

11. The Ionosphere: The F-layer • F1: Chapman layer • Ionization of O(i.e. atomic oxygen) at even shorter wavelengths (l<91.1nm) • O+ reacts with O2 and N2 to create ionized molecules • F2: modified Chapman Layer • Ionization of O(i.e. atomic oxygen) at still shorter wavelengths (l<80nm) • Also some ionization of N2

12. 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

13. Ionosphere electron desnisty