Earth Observatory Glossary
(Starting with "V")
By
NASA,
Program Manager: David Herring,
Responsible NASA official: Dr. Michael D. King,
U.S.A.
http://earthobservatory.nasa.gov/Library/glossary.php3?mode=all
Become a member of TranslationDirectory.com at just
$12 per month (paid per year)
Advertisements:
Use the search bar to look for terms in all glossaries, dictionaries, articles and other resources simultaneously
| |
validation |
Comparing a climate model's predictions with observations of the real climate, in order to test the reliability and accuracy of the model. The most obvious way to test a climate model is to use it to analyze past events, and then see whether its simulated prediction 'came true,' or how close it was to being correct. |
| | | |
| |
Van Allen belts or Van Allen Radiation belts |
Doughnut-shaped regions encircling Earth and containing high energy electrons and ions trapped in the Earth's magnetic field (the magnetic field has definite boundaries, and is distorted into a tear-drop shape by the solar wind). Explorer I, launched by NASA in 1958, discovered this intense radiation zone. These regions are called the inner and outer Van Allen radiation belts, named after the scientist who first observed them. See magnetosphere. |
| | | |
| |
vector |
A physical quantity that has both a magnitude and a direction and that adds like displacement; velocity, acceleration, and force are prime examples. |
| | | |
| |
vector-borne disease |
A vector-borne disease is one in which the pathogenic microorganism is transmitted from an infected individual to another individual by an arthropod or other agent, sometimes with other animals serving as intermediary hosts. The transmission depends upon the attributes and requirements of at least three different living organisms: the pathologic agent, either a virus, protozoa, bacteria, or helminth (worm); the vector, which are commonly arthropods such as ticks or mosquitoes; and the human host. In addition, intermediary hosts such as domesticated and/or wild animals often serve as a reservoir for the pathogen until susceptible human populations are exposed. See Mapping Malaria |
| | | |
| |
Vegetation Canopy Lidar (VCL) |
The first satellite mission of NASA's Earth System Science Pathfinder project that will create the first maps of the three-dimensional structure of vegetation in the world's forests. The VCL lidar holds five lasers that each send 242 pulses per second at the Earth's surface. Each beam covers an area 75 feet across. By spacing the five beams a little over a mile apart, each VCL orbit will sample an area 5 miles across. See VCL fact sheet. |
| | | |
| |
velocity |
The time rate at which a body changes its position vector; velocity is a vector quantity whose magnitude is expressed in units of distance over time, such as miles per hour. (From the Latin word for "speed.") |
| | | |
| |
vernal equinox |
The beginning of spring in the Northern Hemisphere. The time/day that the sun crosses the equatorial plane going from south to north. |
| | | |
| |
visible |
That part of the electromagnetic spectrum to which the human eye is sensitive, between about 0.4 and 0.7 micrometers. See spectrum. |
| | | |
| |
Visible/Infrared Spin Scan Radiometer (VISSR) |
High-resolution, multi-spectral imaging system flown on the pre-GOES-8 geostationary GOES spacecraft. Similar systems are flown on the METEOSAT and GMS spacecraft. |
| | | |
| |
volcano |
A naturally occurring vent or fissure at the Earth's surface through which erupt molten, solid, and gaseous materials. Volcanic eruptions inject large quantities of dust, gas, and aerosols into the atmosphere. A major component of volcanic clouds is sulfur dioxide, a strong absorber of ultraviolet radiation. Chemical interactions between sulfur dioxide and water cause sulfuric acid aerosols which can scatter some of the incident solar radiation back to space, thus causing a global cooling effect. For example, Mt. Pinatubo in the Philippines erupted in June 1991, and in the following year the global surface temperature was observed to decrease by about 0.3 degrees C. |
| | | |
| |
vortex |
A mass of fluid rotating about an axis, i.e., whirlpool or whirlwind. |
Find free glossaries at TranslationDirectory.com
Find free dictionaries at TranslationDirectory.com
Subscribe to free TranslationDirectory.com newsletter
Need more translation jobs from translation agencies? Click here!
Translation agencies are welcome to register here - Free!
Freelance translators are welcome to register here - Free!
Submit your glossary or dictionary for publishing at TranslationDirectory.com
|
