Thermal
A thermal is a column of rising air in the lower altitudes of the Earth's atmosphere. Thermals are created by the uneven heating of the Earth's surface from solar radiation. See convection.
The size and strength of thermals are influenced greatly by the properties of the lower atmosphere. The most important factor is the amount of atmospheric stability. Generally, when the atmosphere is less stable thermal formation is more likely.
Thermals are often indicated by the presence of visible cumulus clouds. The rising air in a thermal cools as it ascends, until the water vapor in the air begins to condense into visible droplets.
Thermal also refers to occurances of heat and things involving heat, or the release there of. A thermal reation refers to a chemical reaction that releases heat. Thermal clothing is clothing that would be worn in extream cold to conserve body heat.
