Earth's Atmosphere & Weather

For test on Tue

troposphere

atmospheric layer closest to Earth's surface; extends to altitudes between 8-15km; where weather occurs; temperature decreases with altitude increase

stratosphere

2nd layer of atmosphere; extends from 15 km to to 50km; location of ozone layer; absorbs 95% of Ultraviolet radiation; temperature increases with altitude increase

mesosphere

extends from 50kim to 85km; (prefix means middle); one of the two layers where most meteors burn up

thermosphere

extends from 85km to 500km; one of the two layers where most meteors burn up

ionosphere

region between 69km and 500km (within the mesophere and thermosphere) that contains ions; it's ions reflect AM radio waves transmitted at ground level

aurora

an atmospheric phenomenon that occurs when ions from the Sun strike air molecules, causing them to emit vivid colors of light; occurs in the ionosphere

exosphere

the outermost region of the atmosphere; molecules move at high speeds after absorbing the Sun's radiation

air pressure

the force that a column of air applies on the air or a surface below it

altitude

height above sea level

radiation

The transfer of energy by electromagnetic waves

electromagnetic radiation

a form of energy that includes radio waves, microwaves, infrared light, visible light, ultraviolet light, X-rays and gamma-rays

radiation balance

balance between incoming solar energy and outgoing energy radiated into space

greenhouse effect

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

conduction

the transfer of thermal energy by collisions between particles of matter

convection

the transfer of thermal energy by the movement of particles within matter

temperature inversion

atmospheric condition in the tropsphere in which warm air traps cooler air near the earth's surface

wind

the movement of air from areas of high pressure to areas of low pressure created by unequal heating of the Earth's surface

trade winds

prevailing winds that blow from east to west from 30 degrees latitude to the equator in both hemispheres

westerlies

prevailing winds that blow from west to east between 30 - 60 degrees latitude in both hemispheres

polar easterlies

prevailing winds that blow from east to west between 60 - 90 degrees latitude in both hemispheres

Coriolis effect

Earth's rotation causes moving air and water to appear to move to the right in the northern hemisphere and to the left in the southern hemisphere; contributes to prevailing winds

jet stream

narrow band of high winds near the top of the troposphere; move cold air from the poles toward the tropics and warm air from the tropics toward the poles

sea breeze

wind that blows from the sea to the land due to local temperature and pressure differences

land breeze

wind that blows from the land to the sea due to local temperature and pressure differences

weather

the atmospheric conditions, along with short-term changes, of a certain place at a certain time

climate

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

weather variables

temperature, precipitation, air pressure, wind speed and direction, humidity, and cloud cover

humidity

amount of water vapor in the air

relative humidity

the amount of water vapor present in the air compared to the maximum amount of water vapor the air could contain at that temperature

dew point

the temperature at which air is saturated and condensation of water vapor can occur

condensation

the change from a gas to a liquid

cloud

a collection of small water droplets or ice crystals suspended in the air, which forms when the air is cooled and condensation occurs

stratus clouds

flat, white, and layered clouds at altitudes up to 2,000 m

cumulus clouds

fluffy, heaped, or piled up clouds at 2,000 - 6,000 m of altitude

cirrus clouds

wispy clouds above 6,000 m of altitude

fog

near surface cloud

nimbus clouds

clouds that produce precipitation that reach the ground in the form of rain, snow or hail

high-pressure system

a large body of circulating air with high pressure at its center and lower pressure outside of the system

low-pressure system

a large body of circulating air with low pressure at its center and higher pressure outside of the system

front

a boundary between two air masses

cold front

dense cold air pushes under warm air mass; thunderstorms followed by cool, fair weather

warm front

moist, warm less dense air slides up and over cold air mass; condenses into broad clouds; brings gentle rain or light snow, followed by warmer, milder weather

stationary front

warm and cold air meet and stand still; clouds and fog form and it may rain or snow--can bring days of clouds and precipitation

occluded front

forms when warm air mass gets caught between two cold air masses; warm air rises as the cold air masses meet in the middle; temperature drops, can bring strong winds and heavy precipitation

Isaac

the coolest student