A Hitchhiking Particle’s Guide to the Terrestrial Atmosphere
This talk will transform the audience into a hydrogen molecule and map its journey through our complicated atmosphere. Along the way, notes about the physical processes that dominate at each layer will be discussed. The audience will pass through a succession of neutral gas layers that are well-mixed and compositionally homogenous with differing temperature profiles. Here the models of hydrostatic equilibrium and heat transfer dictate the equations of state of each molecular species. Further up strange encounters begin to occur for our new particle. Experiences with ionized matter should baffle and frighten the average hydrogen molecule at the Earth’s surface; DONT PANIC, there will be no danger for the audience in the talk. Eventually, the molecule will lose its diatomic status and become two atomic particles. Even further and the temperature becomes prohibitive for a bound electron and a proton, or atomic hydrogen. As soon as the audience becomes charged, strange forces will begin to act upon them. Above 500 km, electromagnetic forces rule the beat. Tugged and bullied by these forces, our audience will visit some of the most famous landmarks for ionized matter: the ionosphere, the polar cusps, the auroral oval, the bow shock and magnetopause, the magnetotail, and the radiation or Van Allen belts.
How would the life of this molecule progress as it is zipped around the atmosphere? What would the particle need to know to get around?