Atmosphere:

The gaseous mass or envelope surrounding a celestial body, especially the one surrounding Earth, and retained by the celestial body's gravitational field.

Climate:

The average weather conditions in an area over a long period of time, taking into account temperature, precipitation, humidity, wind, atmospheric pressure, and other phenomena. The major factor governing climate is latitude; this is modified by one or more secondary factors including position relative to land and water masses, altitude, ocean currents, topography, prevailing winds, and prevalence of cyclonic storms.

Coriolis effect:

The tendency for any moving body on or above the earth's surface to drift sideways from its course because of the earth's rotational direction (west to east) and speed, which is greater for a surface point near the equator than toward the poles. In the Northern Hemisphere the drift is to the right of the motion; in the Southern Hemisphere, to the left.

Easterlies/Trade Winds:

Winds over the Pacific Ocean that blow East to West along the equator.

El Nino--a.k.a. El Niño/Southern Oscillation Event:

The change in global weather patterns that takes place when the Southern Oscillation Index is at its lowest extreme. Characterized by a level Pacific thermocline, warm Easter Pacific and low pressure/heavy rain over the central and Eastern Pacific.

Fossil Fuel:

A hydrocarbon deposit, such as petroleum, coal, or natural gas, derived from living matter of a previous geologic time and used for fuel.

Greenhouse Effect:

The phenomenon whereby the earth's atmosphere traps solar radiation, caused by the presence in the atmosphere of gases such as carbon dioxide, water vapor, and methane that allow incoming sunlight to pass through but absorb heat radiated back from the earth's surface.

Humboldt Current:

Ocean current moving from North to South along the Eastern Pacific coast.

Jet Stream:

La Niña:

The change in global weather patterns when the Southern Oscillation Index is at its highest extreme. Characterized by a steep Pacific thermocline, very warm Western Pacific and very cold Eastern Pacific, and low pressure/heavy rain over the Western Pacific coast.

North Equatorial Current

Ocean current moving from East to West just North of the Equator in the Pacific Ocean.

Photosynthesis:

The process in green plants and certain other organisms by which carbohydrates are synthesized from carbon dioxide and water using light as an energy source. Most forms of photosynthesis release oxygen as a byproduct.

Southern Oscillation

Yearly variations in atmospheric pressure differences between the East and West Pacific.

Southern Oscillation Index (SOI):

Measure for the Southern Oscillation. Measures the difference in atmospheric pressure between Darwin, Australia and Tahiti.

Thermocline:

The level in the ocean at which water temperatures are about 17 degrees Celsius. Above, water is warmer, below it is colder.

Trade Wind:

Any of a consistent system of prevailing winds occupying most of the tropics, constituting the major component of the general circulation of the atmosphere, and blowing northeasterly in the Northern Hemisphere and southeasterly in the Southern Hemisphere.

Walker Circulation:

 

Weather:

State of the atmosphere at a given time and place with regard to temperature, air pressure, humidity, wind, cloudiness, and precipitation. The term weather is restricted to conditions over short periods of time.

Westerlies: