Physical Therapy Assistant Guide. Welcome to the PTA Guide, a physical therapy assistant education & career resource. We have everything you need to become a licensed PTA in your state. A few of the helpful things that you'll find here are information resources by state such as tools and info on PTA Schools, PTA license requirements, PTA Jobs, PTA salary data for states & major cities.
A dust devil in Ramadi, Iraq. Atmospheric instability is a condition where the Earth's atmosphere is generally considered to be unstable and as a result the weather is subjected to a high degree of variability through distance and time.hese indices, as well as atmospheric instability itself, involve temperature changes through the troposphere with height, or lapse rate. Effects of atmospheric instability in moist atmospheres include thunderstorm development, which over warm oceans can lead to tropical cyclogenesis, and turbulence.
The atmospheric atoms and molecules are impacted by the high energy the EUV and X-ray photons from the sun. The amount of energy (photon flux) at EUV and x-ray wavelengths varies by nearly a factor of ten over the 11 year solar cycle. The density of the ionosphere changes accordingly. Due to spectral variability of the solar radiation and the density of various constituents in the atmosphere, there are layers are created within the ionosphere, called the D, E, and F-layers.