The Atmosphere

Atmosphere

Commonly called "air," this mixture of gases is composed of about 78% nitrogen (N2) and about 21% oxygen (O2). The remaining 1% includes trace gases such as argon and carbon dioxide.

Aerosols

Small particles of dust, salt, spores, pollen, smoke, volcanic ash and more, suspended in the atmosphere

Atmospheric Pressure

force exerted on a surface by the air above it

Barometer

An instrument that measures atmospheric pressure

Atmosphere (ATM)

A unit of measurement for gas pressure. One atmosphere is equivalent to 14.7 pounds of pressure per square inch, 1,013 millibars, or a barometric reading of 760 millimeters of mercury.

Pressure - Altitude Relationship

Atmospheric pressure decreases as altitude increases.

Troposphere

Lowest layer of the atmosphere, 0-17 km above Earth's surface, site of weather, organisms, contains most atmospheric water vapor and atmospheric mass. (temperature decreases with increasing altitude, pressure decreases)

Stratosphere

Second lowest layer of the atmosphere, ozone layer is here which absorbs UV radiation

Ozone

a gas molecule that is made up of three oxygen atoms

Mesosphere

The layer of Earth's atmosphere immediately above the stratosphere, has the coldest atmospheric temperatures.

Thermosphere

the region of the atmosphere above the mesosphere and below the height at which the atmosphere ceases to have the properties of a continuous medium. The thermosphere is characterized throughout by an increase in temperature with altitude.

Exosphere

The outer layer of the thermosphere, extending outward into space.

Weather

meteorological conditions including temperature, wind speeds, and precipitation at a given time, in a specific location, which is subject to change.

Climate

The average weather conditions in an area over a long period of time

Air Mass

A large body of air that has similar temperature, humidity, and air pressure at any given height

Front

The boundary where air masses with differing densities meet and where adverse weather conditions typically occur as a result.

Convection

The transfer of heat by the movement of a fluid

Hadley Cell

a system of vertical and horizontal air circulation predominating in tropical and subtropical regions and creating major weather patterns.

Ferrell Cell

The middle atmospheric circulation cell in each hemisphere. Air in these cells rises at 60 degrees latitude and fall at 30 degrees latitude

Polar Cell

Cells of air circulation occurring between 60 degrees north and south and each pole.

Convection Cells

Circulations of air, moisture and heat around the Earth.

Prevailing Winds

Global winds that blow constantly from the same direction. Include the polar easterlies that originate in the poles, the westerlies in the middle latitudes, and the trade winds that blow in the tropics.

Coriolis Effect

Causes moving air and water to turn left in the southern hemisphere and turn right in the northern hemisphere due to Earth's rotation.

Thermometer

An instrument used to measure temperature

Hygrometer

an instrument for measuring the humidity of the air or a gas.

Anemometer

An instrument used to measure wind speed and direction of prevailing winds in a localized area.

Florida Climate and Seasons

The climate in the north and central parts of Florida is considered to be humid subtropical. South Florida has a tropical climate. There is a defined rainy season that lasts from May through October, when the air mass thunderstorms that build in the heat of the day drop heavy but brief episodes of rainfall. Two seasons: Wet and Dry.

Precipitation

rain, snow, sleet, or hail that falls to the ground.

Obscuration

Phenomena in the atmosphere other than precipitation that reduces horizontal visibility, such as mist, fog, smoke, volcanic ash, dust, sand and haze.

"Other" Meteorological Disturbances

Includes phenomena that don't fall into the previous two categories and that are related to wind, such as dust/sand whirls, squalls, tornadoes, funnel clouds, waterspouts, sand storms and dust storms.

Saffir-Simpson Scale

Scale that classifies hurricanes according to wind speed.

Greenhouse Effect

Natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases.

Deforestation

The removal of trees faster than forests can replace themselves.

Contributor of greenhouse gases into the atmosphere.

Fossil Fuels

Coal, oil, natural gas, and other fuels that are ancient remains of plants and animals.

Burning of fossil fuels is a contributor to greenhouse gases in the atmosphere.

Carbon dioxide

a colorless, odorless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in air and is absorbed by plants in photosynthesis.

Global Warming

An increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)

Climate Change

a change in global or regional climate patterns, in particular a change apparent from the mid to late 20th century onwards and attributed largely to the increased levels of atmospheric carbon dioxide produced by the use of fossil fuels.

Ocean Acidification

decreasing pH of ocean waters due to absorption of excess atmospheric CO2 from the burning of fossil fuels

Desertification

Degradation of land, especially in semiarid areas, primarily because of human actions like excessive crop planting, animal grazing, and tree cutting.

Air Pollution

the contamination of the atmosphere by the introduction of harmful substances from human and natural sources

Montreal Protocol

meeting in 1987 where a group of nations met in Canada and agreed to take steps to fight against Ozone Depletion-CFC's banned

Particulate Matter

a small discrete mass of solid or liquid matter that remains individually dispersed in gas or liquid emissions (usually considered to be an atmospheric pollutant)

Nitrogen dioxide

produced from humans by vehicle emissions, contributes to photochemical smog

Sulfur dioxide

A colorless, corrosive gas directly damaging to both plants and animals. When mixed with suspended water droplets, sulfur dioxide forms sulfuric acid - a component of acid rain.

Carbon monoxide

a colorless, odorless gas produced by the burning of fossil fuels. Extremely harmful (poisonous) when breathed.