Search results
Results from the WOW.Com Content Network
Atmospheric instability is a condition where the Earth's atmosphere is considered to be unstable and as a result local weather is highly variable through distance and time. [ clarification needed ] [ 1 ] Atmospheric instability encourages vertical motion, which is directly correlated to different types of weather systems and their severity.
A stable atmosphere makes vertical movement difficult, and small vertical disturbances dampen out and disappear. In an unstable atmosphere, vertical air movements (such as in orographic lifting , where an air mass is displaced upwards as it is blown by wind up the rising slope of a mountain range) tend to become larger, resulting in turbulent ...
Lake stratification, the formation of water layers based on temperature, with mixing in the spring and fall in seasonal climates. Atmospheric instability; Atmospheric stratification, the dividing of the upper reaches of the Earth's atmosphere into stably-stratified layers; Atmospheric circulation, caused by the unstable stratification of the ...
The saturated adiabatic lapse rate (SALR), or moist adiabatic lapse rate (MALR), is the decrease in temperature of a parcel of water-saturated air that rises in the atmosphere. It varies with the temperature and pressure of the parcel and is often in the range 3.6 to 9.2 °C/km (2 to 5 °F/1000 ft ), as obtained from the International Civil ...
Atmospheric convection is the result of a parcel-environment instability (temperature difference layer) in the atmosphere. [ jargon ] Different lapse rates within dry and moist air masses lead to instability.
Certain criteria need to be met for their formation. In most situations, water temperatures of at least 26.5 °C (79.7 °F) are needed down to a depth of at least 50 m (160 ft); [21] waters of this temperature cause the overlying atmosphere to be unstable enough to sustain convection and thunderstorms. [22]
Because of its temperature, the atmosphere emits infrared radiation. For example, on clear nights Earth's surface cools down faster than on cloudy nights. This is because clouds (H 2 O) are strong absorbers and emitters of infrared radiation. This is also why it becomes colder at night at higher elevations.
Unstable areas are in yellow (slightly) and red (highly) while the stable zone is in blue. The lifted index (LI) is the temperature difference between the environment Te(p) and an air parcel lifted adiabatically Tp(p) at a given pressure height in the troposphere (lowest layer where most weather occurs) of the atmosphere, usually 500 hPa . The ...