87 terms

CHAPTER 24 - 24.1, 24.2, 24.4, 24.5 & 24.7

The Atmosphere pg 746
Air Pressure
1- the weight of air
2- the result of the weight of the air pushing down on the area
3- decrease as altitude increases
4- will not crush objects because
molecules push in all directions
the distance above sea level
Aneroid Barometer
Instrument that measures changes in air pressure
without using a liquid
1- The layer of gases that surrounds Earth
2- water droplets & solid particles are in the atmosphere
3- forms a protective boundary to make Earth's temperature suitable for life

NOTE: The atmosphere is 99% of the gases Nitrogen & Oxygen + Water Vapor
1- a colorful light display in the sky - the Northern lights
2- this happens when particles from the sun are attracted to the Earth's magnetic poles
the instrument (tool) used to
measure changes in air pressure
1- the amount of mass in a unit
volume of a substance
2- decreases as air pressure decreases
Gases that are Essential for Life
1- Nitrogen
2- Oxygen
3- Carbon dioxide
1- the lower layer of the thermosphere
2- this is where nitrogen & oxygen lose electrons
3- auroras happen because of he glowing ions in this layer of the atmosphere
Mercury Barometer
instrument that measures changes in air
pressure using liquid mercury
1- 3rd layer above the stratosphere & air is very thin
2- 50km to 80km
3- temperature decreases as altitude increases
4- most meteoroids that are coming toward the earth are burned up in this part of the atmosphere
Ozone Layer
1- a layer of ozone gas
2- this is where the highest reactive gas is
3- radiation in sunlight is absorbed by ozone before it reaches Earth

Note: Chemicals are destroying the ozone layer.
force per unit area
1- this is where the ozone layer is
2- 2nd layer above the troposphere
3- 12km to 50km
4- temperature increases as altitude increases
1- 4th layer - the thin air here blends with outer space
2- 80km into outer space
3- the outer layer is called the exosphere (this is where satellites orbit the Earth)
4- the lower layer is called the Ionosphere
3- temperature increases rapidly - is quite high
1- this is where we live
2- closest to the Earth's surface
3- 9km above the poles to 16km above the tropics
4- temperature decreases as altitude increases
is what's happening in the atmosphere outside
The Sun and the Seasons pg 752
EARTH - TRUE Statements
1- It takes 1 DAY (24 hours) to complete 1 ROTATION
2- It takes 1 YEAR for the Earth to complete a REVOLUTION
3- is warmer near the equator and colder toward the Poles
the part of Earth that RECEIVES THE MOST
the two days of the year on which neither hemisphere is tilted toward or away from the sun
it marks out three different types of regions with similar temperatures
North Star
the North end of Earth's axis points to this
the PATH Earth takes around the sun
Polar Zones
from 66.5 degrees north to the North Pole and from 66.5 degrees south to the South Pole (Cold)
the movement of one body of space around another
the spinning of Earth on its axis
The Seasons
are caused by the tilt of Earth's axis as it moves around the sun
Note: Summer, Fall, Winter, Spring
The two days of the year where the noon sun is directly overhead at either 23.5 degrees
South or 23.5 degrees North
Temperate Zones
- where the Earth is cooler than the Tropics
- the United States is in this REGION
Tropic Zone
between the latitudes of 13.5 degrees
south and 23.5 degrees north
Vernal Equinox
Begins the Spring season
Water in the Atmosphere pg 760
Cirrus Clouds
thin, white, wispy clouds with a feathery appearance
1- a dense, visible mass of tiny water droplets or ice crystals that are suspended in the atmosphere
2- Clouds are classified by their form and height
Cloud Forms
3 basic Types of cloud forms:
a) Stratus b) Cumulus c) Cirrus
Cumulus Clouds
Puffy white clouds that look like piles of cotton
balls with flat bottoms
Dew point
1- the temperature at which air becomes saturated
2- Clouds may form when moist air rises and the temperature cools below the Dew Point.
NOTE: Water vapor condenses as dew, frost, clouds or fog
When water vapor in air changes directly from a gas to a solid
the amount of water vapor in the air
Relative humidity
the ratio of the amount of water vapor in the air to the maximum amount of water vapor the air
can hold at a set temperature
Stratus Clouds
flat layers of clouds that cover
much or all of the sky
Weather Patterns pg 765
Air Mass
1- a huge body mass of air that has similar temperature, humidity, and air pressure at any given height
Swirling center of high air pressure. Spin outwards and draws in air from troposphere. Dry and clean.

Includes clear skies, very little precipitation, and
generally calm conditions
Cold Front
Fast cold air slides underneath slow and warm air
dry air masses that form over land
1- Swirling center of low air pressure. Warm air rises through eye, sucks in air from ground. Clouds, wind and precipitation.
3- Cyclones have clouds, precipitation
and stormy weather.
Move away temporarily
NOTE: When there is a fire in an area, they evacuate the homes and the town
1- the area where two unlike air masses meet
2- forms when a continental polar air mass collides with a maritime tropical air mass
Fronts (4 Types)
Cold Front, Warm Front, Stationary Front, Occluded Front
a large tropical storm (cyclone) that begins over warm, low pressure and water; with heavy rain and winds up to 119 km per hour.
Hurricane safety
Joining lines on the place with identical air pressure.
Joining lines on the place with identical temperatures.
jet streams
high and speedy streams within the prevailing westerlies
a sudden spark, or electrical discharge, between the cloud and the ground
humid air masses that form over water
Scientists who study the causes of weather and predict the kind of weather that is coming
Occluded Fronts
During the front: Cold air on ground
After the front: Clouds, rain, or snow
cold air masses with high air pressure
prevailing westerlies
push air masses from west to east
Snowstorm safety
Find shelter from the wind, and stay warm
Stationary Front
a front that occurs when two air masses have formed a boundary but neither is moving (p 768)
a violent disturbance in the atmosphere
storm surge
a "dome" of water that sweeps across the coast where a hurricane lands
the sound caused by
the rapid expansion of
air along an electrical strike
Small storm with heavy rain formed in cumulonimbus clouds. Accompanied by thunder, lightning, and strong winds.
thunderstorm safety
avoid conductors of electricity and high areas
a rapidly whirling, funnel-shaped cloud that reaches down from a cumulonimbus storm cloud to touch Earth's surface
tornado safety
Avoid doors, windows and debris. Lie down under a stable object. The best place to be is in the basement of a well built building.
warm air masses with low air pressure
Warm Front
1- Fast warm air overtakes slow cold air.
2- a front that occurs when a warm air mass overtakes a cold air mass (p 768)
Weather balloons
Balloons that carry instruments into the lower atmosphere
weather satellites
satellites that help meteorologists study weather patterns around the world
Climate p. 778
The long term weather conditions of a place or region.
Climate Groups - 6 Major ones
1- Tropical rainy
2- Temperature continental
3- Dry
4- Temperature marine
5- Polar
6- Highlands
extremely dry region receiving less than 25 cm of rain per year
El Nino
1- the periodic warming of water in the central and easern Pacific Ocean (p 781)
2- a short term variation in climate that is caused by a change in the normal direction of winds, which causes ocean currents to shift direction.
global warming
This process refers to an increase in the worldwide temperature of the lower atmosphere.
1- Carbon dioxide and other gases to the atmosphere may cause this
Greenhouse effect
occurs when certain gases absorb radiation from Earth's surface and then radiate energy back toward the surface
ice ages
Glaciers covered a portion of Earth's surface and temperatures were colder than usual
1- the main factor that determines the amount of solar radiation received by a region
2- the amount of the sun's energy that reaches earth at a given time and place
Region's Precipitation -
4 Factors that affect it are:
1- the existence of a mountain barrier
2- distribution of air pressure systems
3- distribution of global winds
4- latitude
Region's Temperature -
4 Factors that affect it are:
1- latitude
2- distance from large bodies of water
3- ocean currents
4- altitude