1 - SPHERES OF THE EARTH Flashcards
The 4 Spheres of the Earth
“lithosphere” (land)
“hydrosphere” (water)
“biosphere” (living things)
“atmosphere” (air)
the whole mass of air surrounding the earth.
a mass of gases surrounding a heavenly body (as a planet).
the air in a particular place. the stuffy atmosphere of this room.
Atmosphere
Earth’s atmosphere stretches from the surface of the planet up to as far as _______ above. After that, the atmosphere blends into space.
10,000 kilometers (6,214 miles)
Not all scientists agree where the actual upper boundary of the atmosphere is, but they can agree that the bulk of the atmosphere is located close to Earth’s surface—up to a distance of around ________.
eight to 15 kilometers (five to nine miles)
The majority of Earth’s atmosphere is _____
nitrogen
Percentage of nitrogen in the atmosphere
78%
Percentage of oxygen in the atmosphere
21%
Percentage of argon in the atmosphere
0.9%
Percentage of other gases in the atmosphere
0.1
Five Layers of the Earth’s Atmosphere
Exosphere
Thermosphere
Mesosphere
Stratosphere
Troposphere
Hot Air Balloon
Passenger Plane
Commercial Jet
Troposphere
Radiosonde
Weather Balloon
Spy Plane
Stratosphere
Meteors
Meteorological Rocket
Mesosphere
Aurora Borealis
Thermosphere
Spaceship
Satellite
Exosphere
The layer closest to Earth’s surface, reaching from about seven and 15 kilometers (five to 10 miles) from the surface.
Troposphere
The troposphere is thickest at the ______, and much thinner at the North and South Poles.
equator
The majority of the mass of the entire atmosphere is contained in the ______—between approximately 75 and 80 percent.
troposphere
Most of the water vapor in the atmosphere, along with dust and ash particles, are found in the troposphere—explaining why most of Earth’s _____ are located in this layer.
clouds
Temperatures in the ________ decrease with altitude.
troposphere
The second layer of the earth’s atmosphere
stratosphere
the top of the troposphere
tropopause
Temperatures in the _______ increase with altitude
stratosphere
Stratosphere reaches from the top of the troposphere, which is called the tropopause, to an altitude of approximately _______
50 kilometers (30 miles).
A high concentration of ozone, a molecule composed of three atoms of oxygen, makes up theozone layerof the ______
stratosphere
This ozone absorbs some of the incoming solar radiation, shielding life on Earth from potentially harmful _______, and is responsible for the temperature increase in altitude.
ultraviolet (UV) light
The top of the stratosphere
stratopause
Above the stratopause is the_______, which reaches as far as about 85 kilometers (53 miles) above Earth’s surface.
mesosphere
Temperatures decrease in the _______ with altitude
mesosphere
the coldest temperatures in the atmosphere are near the top of the ______—about -90°C (-130°F).
mesosphere
The atmosphere is thin here, but still thick enough so that meteors will burn up as they pass through the mesosphere—creating what we see as ______
“shooting stars.”
The upper boundary of the mesosphere is called the ______
mesopause.
The_______is located above the mesopause and reaches out to around 600 kilometers (372 miles).
thermosphere
Not much is known about the _______ except that temperatures increase with altitude.
thermosphere
________ makes the upper regions of the thermosphere very hot, reaching temperatures as high as 2,000°C (3,600°F).
Solar radiation
The uppermost layer, that blends with what is considered to be outer space
exosphere
The pull of Earth’s gravity is so small in the exosphere that molecules of gas escape into _______
outer space.
the total amount of water on a planet.
hydrosphere
The hydrosphere includes water that is on the
surface of the planet
underground
air
Forms of hydrosphere
liquid
vapor
ice
liquid water exists on the surface in the form of
oceans
lakes
rivers
liquid water below ground
groundwater
wells
aquifers
Water vapor is most visible as
clouds
fogs
The frozen part of Earth’s hydrosphere is made of
ice
glaciers
ice caps
icebergs
The names of the frozen part of the hydrosphere
cryosphere
The ocean is a huge body of saltwater that covers about ______ of Earth’s surface.
71%
The planet has one global ocean, though oceanographers and the countries of the world have traditionally divided it into four distinct regions:
Pacific
Atlantic
Indian
Arctic
In 2021, National Geographic officially recognized this fifth ocean.
Southern Ocean
Two of the deepest parts of the ocean.
Philippine Trench
Mariana Trench
This Ocean is relatively shallow because large parts of itsseafloorare made up of continental shelves—parts of the continents that extend far out into the ocean. The average depth of the entire ocean is 3,720 meters (12,200 feet).
Atlantic
is a body of water that is surrounded by land.
Lake
Other lakes are so big that they are called seas. The ______, in Europeand Asia, is the world’s largest lake, withan area of more than 370,000 squarekilometers (143,000 square miles).
Caspian Sea
Lakes also vary greatly in depth. The world’s deepest lake is _____, in Russia. Its bottom is nearly 2 kilometers (more than 1 mile) below the surface in places.
Lake Baikal
