| 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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| image resolution: |
| for pictures or imager data, indicates the number of pixels per unit of length, often measured in dpi (dots per inch). Said to be higher resolution as dpi increases, showing more image detail.
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| independent variable: |
| a variable that can be manipulated or changed, e.g. time scale divisions: hours, days, weeks, etc. On a simple X-Y coordinate graph the independent variable is always on the X-axis.
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| infrared: |
| Of or relating to invisible (to the human eye) radiation with wavelengths in the range from about 750 nanometers, just longer than red in the visible spectrum, to 1 millimeter, on the border of the microwave region.
The Electromagnetic Spectrum
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| in situ: |
| a measurement taken at a location of interest, usually in the troposphere by ground or airborne instruments, as opposed to a measurement made routinely by satellite.
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| insolation: |
| an abbreviated term for incoming solar radiation.
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| ionosphere: |
| The part of the atmosphere between the mesosphere and exosphere. Sufficient quantities of ions and free electrons exist to reflect or refract electromagnetic (especially radio) waves. This layer is what makes long-distance radio communication on Earth possible.
The Earth's Atmosphere
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| irradiance: |
| the rate of energy transfer onto a unit surface area from a hemisphere of directions. Usually measured as watts (energy) per square meter (area).
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Image courtesy MIT |
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| ISCCP: |
| The International Satellite Cloud Climatology Project was established in 1982 as part of the World Climate Research Programme (WCRP) to collect and analyze the global distribution of clouds, their properties, and their diurnal, seasonal, and interannual variations.
The ISCCP Web Site
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| ITCZ: |
| The Intertropical Convergence Zone; a zonal band of low atmospheric pressure and thunderstorms caused by converging Trade Winds, rising air and intense thermal heating at or near the Equator; the location of the ITCZ shifts throughout the year resulting in wet and dry seasons in countries located in the tropics.
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Image courtesy NASA's Visible Earth |
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