15 results. (Showing 1 - 15)

1. gale warning
Warns the public that sustained winds of 34 to 47 knots (39 to 54 mph) inclusive are expected or occurring, and are not directly associated with tropical cyclones.

2. general circulation model (GCM )
A global, three-dimensional computer model of the climate system which can be used to simulate human-induced climate change. GCMs are highly complex and they represent the effects of such factors as reflective and absorptive properties of atmospheric water vapor, greenhouse gas concentrations, clouds, annual and daily solar heating, ocean temperatures and ice boundaries. The most recent GCMs include global representations of the atmosphere, oceans, and land surface.

3. geostationary satellite
A satellite that rotates at the same rate as the earth, thus remaining over the same spot above the equator.

4. global warming
The progressive gradual rise of the earth's surface temperature thought to be caused by the greenhouse effect and responsible for changes in global climate patterns. An increase in the near surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases.

5. goes
Geostationary Operational Environmental Satellite.

6. greenhouse effect
The effect produced as greenhouse gases allow incoming solar radiation to pass through the Earth's atmosphere, but prevent part of the outgoing infrared radiation from the Earth's surface and lower atmosphere from escaping into outer space. This process occurs naturally and has kept the Earth's temperature about 59 degrees F warmer than it would otherwise be. Current life on Earth could not be sustained without the natural greenhouse effect.

7. greenhouse gas
Any gas that absorbs infrared radiation in the atmosphere. Greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, halogenated fluorocarbons (HCFCs), ozone, perfluorinated carbons (PFCs), and hydrofluorocarbons (HFCs).

8. Greenwich Mean Time (GMT )
GMT is the global standard for time that was established in 1884 when delegates from 27 nations met in Washington, DC for the Meridian Conference and agreedon a system basically the same as that now in use. Civilian designations are typically three letter abbreviations (e.g. EST) for most time zones. Military designations use each letter of the alphabet (except 'J') and are known by their phonetic equivalent. For example, Greenwich Mean Time (civilian) or Z = Zulu (military and aviation). Universal Time Coordinated (UTC) has been substituted for GMT.

9. Ground Clutter
A pattern of radar echoes from fixed ground targets (buildings, hills, etc.) near the radar. Ground clutter may hide or confuse precipitation echoes near the radar antenna.

10. ground fog
Fog produced over the land by the cooling of the lower atmosphere as it comes in contact with the ground. Also known as radiation fog.

11. Growing Degree Days
A heat index that relates the development of plants, insects, and disease organisms to environmental air temperature. The index varies depending on whether it is a cool, warm, or very warm season plant. For example, a corn growing degree day (GDD) is an index used to express crop maturity. The index is computed by subtracting a base temperature of 50oF from the average of the maximum and minimum temperatures for the day. Minimum temperatures less than 50oF are set to 50, and maximum temperatures greater than 86oF are set to 86. These substitutions indicate that no appreciable growth is detected with temperatures lower than 50 or greater than 86. If the maximum and minimum temperatures were 85 and 52, you would calculate the GDD by ((85+52/2) - 50) = 18.5 GDD.

12. Gunge
[Slang], anything in the atmosphere that restricts visibility for storm spotting, such as fog, haze, precipitation (steady rain or drizzle), widespread low clouds (stratus), etc.

13. gust
A brief sudden increase in wind speed. Generally the duration is less than 20 seconds and the fluctuation greater than 10 mph.

14. gust front
The leading edge of gusty surface winds from thunderstorm downdrafts; sometimes associated with a shelf cloud or roll cloud.

15. Gustnado (or Gustinado)
[Slang], gust front tornado. A small tornado, usually weak and short-lived, that occurs along the gust front of a thunderstorm. Often it is visible only as a debris cloud or dust whirl near the ground. Gustnadoes are not associated with storm-scale rotation (i.e. mesocyclones); they are more likely to be associated visually with a shelf cloud than with a wall cloud.