| GLOSSARY |
Our comprehensive earth science glossary is available to assist in your understanding of the MY NASA DATA microsets, lesson plans and computer tools. Please select the first letter of the word you wish to check for a definition and further information. |
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| day length: |
| the daily period of time of insolation for a given location, meaning, how long the Sun is above the horizon.
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| degree: |
| a standard unit of measure for several purposes to include temperature on a scale such as Celsius, Fahrenheit or Kelvin, latitude or longitude to locate or designate places on Earth, and planar angles equal to a 360th of a circle.
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Image courtesy NASA explores |
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| dependent variable: |
| a variable that changes in response to the independent variable. On a simple X-Y coordinate graph the dependent variable is usually on the Y-axis.
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| desert dust: |
| Aerosols comprising of minerals from arid and semi-arid regions that absorb sunlight as well as scatter sunlight. Through absorption of sunlight, the dust particles warm the layer of the atmosphere where they reside. This warmer air is believed to inhibit the formation of storm clouds. Desert dust is also a source of nutrients for many remote regions.
Earth Observatory article on aerosols
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| dew point: |
| the temperature to which an air mass must be cooled in order for the air mass to become saturated (relative humidity equals 100 percent), assuming constant pressure and moisture content. Additional moisture would condense into water droplets.
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| difference plot: |
| a plot showing the difference between two sets of data (graphed value = data value 1 - data value 2). A zero measurement means that both sets of data are identical, whereas a high number indicates values are far apart. The difference can be positive or negative depending on which variable has the greater value and the order of subtraction. If creating a difference plot between two different variables, the units of measurement must match.
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| divergence: |
| the horizontal outflow of air from a particular area; if at the surface, causes sinking vertical motion in the atmosphere.
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