sphero-, spher-, -sphere-
(Greek: ball, round, around; globe, global; body of globular form; by extension, circular zone, circular area)
2. The study of the optical characteristics of the atmosphere or products of atmospheric processes.
The term is usually confined to visible and near visible radiation; however, unlike meteorological optics, it routinely includes temporal and spatial resolutions beyond those discernible with the naked eye.
Meteorological optics is that part of atmospheric optics concerned with the study of patterns observable with the naked eye./P>
This restriction is often relaxed slightly to allow the use of simple aids; such as, binoculars or a polarizing filter.
Topics included in meteorological optics are sky color, mirages, rainbows, halos, glories, coronas, and shines.
2. The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.
3. The average atmospheric pressure at sea level is approximately 14.7 pounds per square inch.
With an increasing altitude, the pressure decreases; for example, at 30,000 feet, approximately the height of Mt. Everest, the air pressure is 4.3 pounds per square inch.
The term is applied in particular to devices used to measure infrared radiation.2. A receiver for detecting microwave thermal radiation and similar weak wide-band signals that resemble noise and are obscured by receiver noise.
The primary application of an atmospheric radiometer has been on board spacecraft measuring atmospheric and terrestrial radiation, and they are mostly used for meteorological or oceanographic remote-sensing.
Their secondary application is also meteorological, as zenith-pointing surface instruments that view the earth's atmosphere in a region above the stationary instrument.
By understanding the physical processes associated with energy emission at these wavelengths, scientists can calculate a variety of surface and atmospheric parameters from these measurements, including air temperature, sea surface temperature, salinity, soil moisture, sea ice, precipitation, the total amount of water vapor and the total amount of liquid water in the atmospheric column directly above or below the instrument.
2. An apparent upward displacement of celestial objects relative to the horizon as light from them is bent toward the vertical by the decreasing density with altitude of the earth's atmosphere.
It is greatest for objects on the horizon and negligible at elevations higher than about 45 degrees.3. The angular difference between the apparent zenith distance of a celestial body and its true zenith distance, produced by refraction effects as the light from the body penetrates the atmosphere.
Any refraction caused by the atmosphere's normal decrease in density with height.
Near surfaces on the earth, those within a few meters or so, are usually dominated by temperature gradients.
2. The rhythmic, periodic oscillation of the earth's atmosphere because of the gravitational effects of the earth, sun, and moon and to the absorption of radiation by the atmosphere.
3. A tidal movement of the atmosphere resembling an ocean tide but caused principally by diurnal temperature changes.
Both the sun and moon produce atmospheric tides, and there also exist both gravitational tides (gravitational attraction of the sun or moon) and thermal tides (differential heating of the atmosphere by the sun).