Glossary: E

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  1. The set of capacities needed to generate and disseminate timely and meaningful warning information to enable individuals, communities and organizations threatened by a hazard to prepare and to act appropriately and in sufficient time to reduce the...
  2. The observation and/or study of an area, object or phenomenon from an aerial distance, frequently using data collected by satellite.
  3. A series of small- to intermediate-sized spacecraft that is the centerpiece of NASA's Earth Science Enterprise (ESE). Planned for launch beginning in 1999, each of the EOS spacecraft will carry a suite of instruments designed to study global climate...
  4. The system that will manage a dataset of Earth science observations to be collected over a 15-year period. Existing data indicates that the Earth is changing, and that human activity increasingly contributes to this change. To monitor these changes...
  5. A project that is responsible for providing scientific and other users access to data from NASA's Earth Science Enterprise. The ESDIS Project provides this access through the development and operation of the Earth Observing System (EOS) Data and...
  6. The Earth regarded as a unified system of interacting components, including geosphere (land), atmosphere (air), hydrosphere (water and ice), and biosphere (life). Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  7. An integrated approach to the study of the Earth that stresses investigations of the interactions among the Earth's components in order to explain Earth dynamics, evolution, and global change. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  8. One of six Keplerian elements, it describes the shape of an orbit. In the Keplerian orbit model, the satellite orbit is an ellipse, with eccentricity defining the 'shape' of the ellipse. When e=0, the ellipse is a circle. When e is very near 1, the...
  9. Science dealing with the interrelationships between living organisms and their environments. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  10. Any natural unit or entity including living and non-living parts that interact to produce a stable system through cyclic exchange of materials. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  11. A warming of the surface waters of the eastern equatorial Pacific that occurs at irregular intervals of 2-7 years, usually lasting 1-2 years. Along the west coast of South America, southerly winds promote the upwelling of cold, nutrient-rich water...
  12. Energy propagated as time-varying electric and magnetic fields. These two fields are inextricably linked as a single entity since time-varying electric fields produce time-varying magnetic fields and vice versa. Light and radar are examples of...
  13. The entire range of radiant energies or wave frequencies from the longest to the shortest wavelengths--the categorization of solar radiation. Satellite sensors collect this energy, but what the detectors capture is only a small portion of the entire...
  14. Method of travel for radiant energy (all energy is both particles and waves), so called because radiant energy has both magnetic and electrical properties. electromagnetic waves are produced when electric charges change their motion. Whether the...
  15. The angle at which an antenna must be pointed above the horizon for optimal reception from a spacecraft. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  16. Bodies in space orbit in elliptical rather than circular orbits because of factors such as gravity and drag. The point where the orbiting satellite is closest to Earth is the perigee, sometimes called peri-apsis or perifocus. The point where the...
  17. A disruption of the functioning of society, causing human, material or environmental damages and losses which do not exceed the ability of the affected society to cope using only its own resources.
  18. The set of agencies, organizations and institutions at local, national, regional and international levels that focus their activities on response, rehabilitation, reconstruction and recovery. The term “humanitarian response community” is mentioned...
  19. The ratio of the radiation emitted by a surface to that emitted by a black body at the same temperature. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  20. The natural greenhouse effect has been enhanced by anthropogenic emissions of greenhouse gases. Increased concentrations of carbon dioxide, methane, and nitrous oxide, CFCs, HFCs, PFCs, SF6, NF3, and other photochemically important gases caused by...
  21. Interacting parts of a single global system of climate fluctuations. ENSO is the most prominent known source of interannual variability in weather and climate around the world, though not all areas are affected. The Southern Oscillation (SO) is a...
  22. The complex of physical, chemical, and biological factors in which a living organism or community exists. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  23. ESA
    European Space Agency. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  24. A bay that formed when a broad river valley was submerged by rising sea level or a sinking coast. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  25. European Organisation for the Exploitation of Meteorological Satellites
  26. The process whereby a body of water becomes rich in dissolved nutrients through natural or man-made processes. This often results in a deficiency of dissolved oxygen, producing an environment that favors plant over animal life. Source: NASA (http://...
  27. Change from a liquid (more dense) to a vapor or gas (less dense) from. When water is heated it becomes a vapor that increases humidity. Evaporation is the opposite of condensation. Source: NASA (http://earthobservatory.nasa.gov/Glossary)
  28. The sum of evaporation and plant transpiration. Potential evapotranspiration is the amount of water that could be evaporated or transpired at a given temperature and humidity, if there was plenty of water available. Actual evapotranspiration can not...