Glossary: L

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  1. A period of stronger-than-normal trade winds and unusually low sea-surface temperatures in the central and eastern tropical Pacific Ocean; the opposite of El Niño. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  2. The characteristics of a land surface as determined by its spectral signature (the unique way in which a given type of land cover reflects and absorbs light). Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  3. Indonesian National Institute of Aeronautics and Space
  4. Active instrument that produces discretely coherent pulses of light (light waves with no phase differences, or with predictable phases differences, are said to be coherent). Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  5. The use of lasers to measure distances. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  6. The heat that is either released or absorbed by a unit mass of a substance when it undergoes a change of state, such as during evaporation, condensation, or sublimation. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  7. The angle between a perpendicular at a location, and the equatorial plane of the Earth. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  8. lava that piles up over a volcanic vent, usually in a rounded mass. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  9. The area of foliage per unit area of ground. Conventionally this refers to the ratio of the area of the upper side of the leaves in a canopy projected onto a flat surface to the area of the surface under the canopy. Occasionally this has been used...
  10. Acronym for 'Light Detection and Ranging,' a technique for performing accurate remote measurements of atmospheric trace gas concentration over ranges of several meters to tens of kilometers. This is done by probing the absorption lines of the gases...
  11. 1. Form of radiant energy that acts upon the retina of the eye, optic nerve, etc., making sight possible. This energy is transmitted at a velocity of about 186,000 miles per second by wavelike or vibrational motion. 2. A form of radiant energy...
  12. A discharge of atmospheric electricity accompanied by a vivid flash of light. During thunderstorms, static electricity builds up within the clouds. A positive charge builds in the upper part of the cloud, while a large negative charge builds in the...
  13. The component of the Earth's surface comprising the rock, soil, and sediments. It is a relatively passive component of the climate system, and its physical characteristics are treated as fixed elements in the determination of climate. Source: NASA (...
  14. The angular distance from the Greenwich meridian (0 degree), along the equator. This can be measured either east or west to the 180th meridian (180 degrees) or 0 degree to 360 degrees W. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  15. The radiation emitted in the spectral wavelength greater than 4 micrometers corresponding to the radiation emitted from the Earth and atmosphere. It is sometimes referred to as 'terrestrial radiation' or 'infrared radiation,' although somewhat...
  16. A horizontal area where the atmospheric pressure is less than it is in adjacent areas. Since air always moves from areas of high pressure to areas of low pressure, air from these adjacent areas of higher pressure will move toward the low pressure...