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Our comprehensive glossary is available to assist in your understanding of the S'COOL lesson plan vocabulary words. Please select the first letter of the word you wish to check for a definition and further information.

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All definitions

Weather word translations
occluded front:
A front in which a warmer or colder air mass, in relation to the air mass (warm front) ahead of it, overtakes the warm front and lifts the warmer air, cutting it off from the Earth's surface. Occluded fronts are usually found around strong low-pressure areas, and are accompanied by a mix of weather.   tutorial on occluded fronts
refers to materials that allow no light to pass through.   (Also see [link to cloud definition])
Opaque Cloud Opacity:
This describes thick clouds which do not allow light to pass directly, although light can diffuse through them. Such thick clouds often look gray. When the sky is overcast, or when these clouds are in front of the Sun, it is impossible to tell where the Sun is..   Opaque Cloud Opacity
Optical Depth:
The optical depth is a measure of the visual or optical thickness of a cloud; that is, of the reduction of light or energy transmitted through the cloud due to interactions with the cloud particles. Optical depth is much more significant to Earth's energy budget than the physical thickness of cloud layers. Unlike height, it is not measured in meters or feet; but is nondimensional. An optical depth below 3 is considered to be thin. Anything above 10 is definitely thick. The same term is also used to describe the optical depth of aerosol (dust, smoke, etc) layers..   Optical Depth Graph
element number eight on the periodic table of elements. It can be described as a colorless odorless gas that makes up 21 percent of the atmosphere by volume.