sphero-, spher-, -sphere-
(Greek: ball, round, around; globe, global; body of globular form; by extension, circular zone, circular area)
2. A critical perturbation of the orbits of closely adjacent low-orbit artificial satellites due to atmospheric resistance; the effects extending over ages of time are semidiameter, period, and decreasing eccentricity.
2. A stratum of the troposphere within which the refractive index varies so as to confine within he limits of the stratum the propagation of an abnormally large proportion of any radiation of sufficiently high frequency, as in a mirage.
Atmospheric ducting is a mode of propagation of electromagnetic radiation, usually in the lower layers of the earth’s atmosphere, where the waves are bent by atmospheric refraction.
A typical datum is about 100 and the field is directed vertically in such a way as to drive positive charges downward.2. A quantitative term indicating the electric field strength of the atmosphere at any specified point in space and time.
3. A measure, in volts per meter, of the electrical energy in a given portion of the earth's atmosphere at a given time.
2. The study of electrical processes occurring within the atmosphere.
3. Electrical phenomena, regarded collectively, that occur in the earth's atmosphere.
These phenomena include not only such striking manifestations as lightning and St. Elmo's fire, but also less noticeable but more ubiquitous effects; such as, atmospheric ionization, the air–earth currents, and other quiescent electrical processes.
The existence of separated electric charges in the atmosphere is a consequence of many minor processes; such as, spray electrification, dust electrification, etc. and a few major processes including, cosmic-ray ionization, radioactive-particle ionization, and thunderstorm electrification.
The maintenance of the prevailing atmospheric electric field is now widely believed to be due to thunderstorm effects.
2. The penetration of human-made or natural objects from a planetary atmosphere by an object approaching from space; especially, of the earth's atmosphere by a re-entering spacecraft.
Extinction increases when the object is closer to the horizon because of the greater thickness of atmosphere through which its light must travel.
The atmosphere protects life on earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night.
On average, this circulation corresponds to large-scale wind systems arranged in several east–west belts that encircle the earth.
2. The radio frequency electromagnetic radiation originating, principally, in the irregular surges of charge in thunderstorm lightning discharges.
Atmospherics are heard as a quasi-steady background of crackling noise (static) on certain radio frequencies; such as, those used to broadcast AM radio signals.
Since any acceleration of electric charge leads to emission of electromagnetic radiation, and since the several processes involved in propagation of lightning lead to very large charge accelerations, the lightning channel acts like a huge transmitter, sending out radiation with frequencies of the order of 10 kHz.
2. A departure from the usual increase or decrease of an atmospheric property with altitude.
It usually refers to an increase in temperature with increasing altitude, which is a departure from the usual decrease of temperature with height.3. A reversal in the normal temperature lapse rate, the temperature rising with increased elevation instead of falling.
Usually, within the lower atmosphere (the troposphere) the air near the surface of the earth is warmer than the air above it, largely because the atmosphere is heated from below as solar radiation warms the earth's surface, which in turn then warms the layer of the atmosphere directly above it.
2. The charging of neutral particles in the atmosphere through violent contact with charged particles.
3. The production of ions in the atmosphere by the loss of an electron from a molecule, typically, for example, by cosmic rays or cosmic radiation.
Cosmic rays and radioactive decay are the main sources of atmospheric ionization.
Radioactivity at the surface can also produce ions in the lowest layer of the atmosphere.
The variable involved is temperature unless specified otherwise. The lapse rate is the rate of decrease with height and not simply the rate of change.
While most often applied to the earth's atmosphere, the concept can be extended to any gravitationally supported ball of gas.2. The rate of decrease of temperature with elevation in the atmosphere.
The environmental lapse rate is determined by the distribution of temperature in the vertical at a given time and place and should be carefully distinguished from the process lapse rate, which applies to an individual air parcel.
2. One of several strata or layers of the earth's atmosphere.
Temperature distribution is the most common criterion used for denoting the various shells.