The Four Earth Systems

Summary

This lesson introduces Earth's four interconnected systems: the atmosphere, lithosphere, hydrosphere, and biosphere. It explains how these systems shape the planet's physical geography and sustain life. The atmosphere provides essential gases, like oxygen and carbon dioxide. The lithosphere includes Earth's rocky crust, contributing to mountain and volcano formation. The hydrosphere contains water in oceans, lakes, and glaciers, driving the water cycle. The biosphere encompasses all living organisms, interacting with the other spheres for survival. The lesson highlights the importance of understanding these systems' interdependencies and their impact on Earth's regions.

Takeaways

• 🌍 The Earth's physical geography consists of oceans, mountains, rivers, weather, climate, and vegetation.
• 🔄 The four Earth systems include the atmosphere (gases), lithosphere (rock), hydrosphere (water), and biosphere (life).
• 🌫️ The atmosphere is made up of layers: exosphere, thermosphere, mesosphere, stratosphere (with 90% of the ozone), and troposphere (where we live).
• 🌱 The biosphere includes all life on Earth and interacts with the other systems, especially in cycles like the carbon and water cycles.
• ☁️ The atmosphere is 78% nitrogen, 21% oxygen, and 1% other gases like argon and carbon dioxide.
• 🌍 The lithosphere includes all the Earth's rock and the processes of plate tectonics, creating mountains, volcanoes, and oceanic plates.
• 🌊 The hydrosphere consists of all water on Earth, including oceans, lakes, rivers, glaciers, and water vapor, all connected through the water cycle.
• 🍃 The carbon cycle transfers carbon between the atmosphere, animals, plants, rocks, and oceans, playing a vital role in life on Earth.
• 💧 Less than 1% of the Earth's water is usable freshwater, making water a highly valuable resource.
• ⚡ Human activities, such as pollution and fossil fuel burning, have significant impacts on all four Earth systems, affecting the atmosphere, hydrosphere, and biosphere.

Q & A

What are the four Earth systems mentioned in the script?

The four Earth systems are the atmosphere, lithosphere, hydrosphere, and biosphere.

What is the atmosphere, and why is it important?

The atmosphere is the envelope of gases surrounding the Earth. It is important because it provides the oxygen we need to live, absorbs ultraviolet radiation through the ozone layer, and plays a key role in regulating the Earth's temperature.

What layers make up the atmosphere, and which is closest to Earth?

The layers of the atmosphere include the exosphere, thermosphere, mesosphere, stratosphere, and troposphere. The troposphere, which is closest to Earth, stretches from the ground to about 9 miles high.

Why is the stratosphere significant for life on Earth?

The stratosphere contains 90% of the atmosphere's ozone, which absorbs and scatters ultraviolet radiation from the Sun, making life on Earth possible by protecting it from harmful radiation.

What is the carbon cycle, and how does it connect with Earth's systems?

The carbon cycle is the transfer of carbon between the atmosphere, animals, plants, rocks, and oceans. It involves processes like breathing, photosynthesis, and decomposition, which interconnect Earth's systems by cycling carbon through them.

How do fossil fuels relate to the carbon cycle?

Fossil fuels are formed from the remains of plants and animals that lived millions of years ago. When burned, they release carbon dioxide back into the atmosphere, contributing to the carbon cycle and increasing atmospheric carbon levels.

What is the lithosphere, and what does it include?

The lithosphere refers to the solid, rocky part of Earth, including the Earth's core, mantle, crust, and the soil from which plants grow. It also includes the tectonic plates that form continents and oceanic crust.

How do plate tectonics affect the lithosphere?

Plate tectonics cause the movement of the Earth's crust, creating new crust through ocean floor spreading and volcanoes, while old crust is pushed back into the mantle. This process shapes and reshapes the Earth's surface.

What is the hydrosphere, and why is it crucial for life on Earth?

The hydrosphere includes all of Earth's water, such as oceans, lakes, rivers, glaciers, and water vapor in the atmosphere. It is crucial because it supports life, regulates climate, and plays a central role in the water cycle.

What percentage of Earth's water is usable by humans, and why is this important?

Less than 1% of Earth's water is usable by humans, as most freshwater is trapped in glaciers and polar ice caps. This limited availability makes water an extremely important and sometimes contested resource.

Outlines

00:00

🌍 Introduction to Earth's Physical Geography

This paragraph introduces the concept of Earth's physical geography, which includes various features like oceans, mountains, rivers, and climate. To explain these features, the 'four Earth systems' are introduced: atmosphere, lithosphere, hydrosphere, and biosphere. These systems are described as spheres, and though 'sphere' typically refers to a round shape, here it refers to different sections unified by specific characteristics. The paragraph concludes by emphasizing that these systems not only have subcomponents but also interconnect with each other.

05:01

🌫️ The Atmosphere: Earth's Protective Gas Layer

This section explores the atmosphere, the envelope of gases surrounding the Earth, starting with its various layers. The exosphere is the highest layer, followed by the thermosphere, mesosphere, and stratosphere, where most ozone is located. The ozone layer protects life on Earth by absorbing harmful ultraviolet radiation. The lowest layer, the troposphere, contains 75% of the atmosphere’s mass and is where we live. The paragraph also covers the composition of the atmosphere, noting that while 21% is oxygen, 78% is nitrogen. The significance of nitrogen in causing decompression sickness for divers is also explained, and carbon dioxide’s role in the carbon cycle is introduced.

🌱 The Carbon Cycle and Its Importance

This paragraph details the carbon cycle, highlighting the importance of carbon dioxide in the atmosphere. It describes how carbon dioxide is exchanged between the atmosphere, animals, plants, and oceans. Carbon is taken in by plants during photosynthesis and is reintroduced into the environment through respiration, decay, and fossilization. Over millions of years, decayed plants and animals become fossil fuels like oil and coal. The paragraph also touches on how the burning of fossil fuels releases carbon back into the atmosphere, potentially contributing to climate change.

🪨 The Lithosphere: Earth's Rocky Layer

This section discusses the lithosphere, which includes all the Earth's rock, from its core to the surface crust. The lithosphere consists of the Earth's mantle, core, and the rocky crust on which we live. It also includes soil, essential for plant growth. The paragraph explains plate tectonics, describing how Earth's crust is constantly being created and destroyed through processes like ocean floor spreading and convergent subduction, which shape the Earth’s surface by creating mountains and volcanoes.

💧 The Hydrosphere: Earth's Water Cycle

This part covers the hydrosphere, which encompasses all water on Earth, including oceans, lakes, glaciers, and water vapor in the atmosphere. It describes the water cycle, where water evaporates, condenses, and falls as precipitation, eventually returning to oceans or percolating into the soil. The text highlights the limited availability of freshwater, noting that less than 1% of Earth’s water is usable by humans, and the rest is either saltwater or frozen in glaciers. This makes water a crucial and sometimes contested resource.

🌱 The Biosphere: Earth's Living Organisms

This paragraph defines the biosphere, the Earth system that includes all life forms, from microbes to whales. It explains how the biosphere is interconnected with the other Earth systems through cycles such as the carbon and water cycles. The paragraph also discusses the life cycle of organisms and how the biosphere contributes to soil fertility through organic material decomposition. Importantly, it emphasizes how the biosphere depends on the other systems for survival, while human activities can impact these systems, especially through pollution and resource depletion.

🔗 Integration of the Four Earth Systems

The concluding paragraph underscores the interconnectedness of the atmosphere, lithosphere, hydrosphere, and biosphere. It highlights how each system influences the others and how human activities can have profound impacts on these systems. For example, overuse of water and pollution can affect the atmosphere and hydrosphere. The text concludes by emphasizing that understanding the interaction of these Earth systems is crucial for comprehending regional impacts around the world.

Keywords

💡Atmosphere

The atmosphere is the envelope of gases surrounding the Earth. It plays a crucial role in supporting life by providing oxygen and shielding the Earth from harmful ultraviolet radiation through the ozone layer. In the video, the atmosphere is described in layers, each with distinct characteristics, and its interactions with other Earth systems are highlighted.

💡Lithosphere

The lithosphere refers to the Earth's solid outer layer, including the crust and upper mantle. It consists of rocks, soil, and the tectonic plates that shape the Earth's surface through movements such as plate tectonics. The video explains how the lithosphere interacts with other spheres, particularly in creating and recycling Earth's surface through processes like volcanism and plate subduction.

💡Hydrosphere

The hydrosphere encompasses all the water on Earth, including oceans, lakes, rivers, glaciers, and water vapor in the atmosphere. It is essential for life and influences weather and climate patterns through the water cycle. The video discusses how water moves between the atmosphere and hydrosphere, and its importance to ecosystems and human life.

💡Biosphere

The biosphere includes all living organisms on Earth, from the smallest microbes to the largest animals. It is deeply interconnected with other spheres, relying on the atmosphere for oxygen, the lithosphere for soil, and the hydrosphere for water. The video emphasizes how the biosphere depends on the other three systems for survival and sustains life through cycles like the carbon and water cycles.

💡Carbon Cycle

The carbon cycle refers to the movement of carbon between the atmosphere, biosphere, lithosphere, and hydrosphere. It involves processes like respiration, photosynthesis, decomposition, and the burning of fossil fuels. The video explains how carbon is exchanged through these systems and highlights its importance for life and its role in climate change due to the burning of fossil fuels.

💡Ozone Layer

The ozone layer is a part of the stratosphere that contains high concentrations of ozone (O3) gas. It protects life on Earth by absorbing most of the Sun's harmful ultraviolet radiation. The video stresses the importance of this layer for sustaining life and how it is a critical part of the atmosphere's ability to shield the Earth.

💡Water Cycle

The water cycle is the continuous process by which water moves between the atmosphere, land, and oceans. It includes evaporation, condensation, precipitation, and runoff. The video describes how water is transferred across different parts of the hydrosphere and atmosphere, supporting ecosystems, agriculture, and human consumption.

💡Plate Tectonics

Plate tectonics refers to the movement of Earth's lithospheric plates, which leads to the formation of mountains, earthquakes, and volcanic activity. In the video, this concept is discussed in relation to how the Earth's crust is continually reshaped as new crust forms and old crust is recycled through subduction.

💡Fossil Fuels

Fossil fuels are natural fuels such as coal, oil, and natural gas formed from the remains of ancient plants and animals over millions of years. The video explains how these fuels, when burned, release stored carbon back into the atmosphere, contributing to the carbon cycle and climate change.

💡Photosynthesis

Photosynthesis is the process by which plants absorb carbon dioxide from the atmosphere and use sunlight to convert it into glucose and oxygen. The video mentions this process as part of the carbon cycle, explaining how plants help regulate carbon levels in the atmosphere and provide energy for the biosphere.

Highlights

Introduction to Earth's physical geography, covering oceans, mountains, rivers, weather, climate, and vegetation.

Explanation of the four Earth systems: atmosphere, lithosphere, hydrosphere, and biosphere.

The atmosphere is described as an envelope of gases around the Earth, consisting of different layers including the exosphere, thermosphere, mesosphere, stratosphere, and troposphere.

The stratosphere contains 90% of the ozone, which is crucial for absorbing and scattering ultraviolet radiation from the Sun.

The troposphere is the thinnest layer of the atmosphere but contains 75% of the atmosphere’s mass.

Explanation of nitrogen’s prevalence in the atmosphere, making up 78%, and its role in decompression sickness for divers.

The carbon cycle is described as the transfer of carbon between the atmosphere, animals, trees, rocks, and oceans.

Fossil fuels such as oil and coal are formed over millions of years from decaying plants and animals.

Lithosphere includes Earth's core, mantle, and crust, and the concept of plate tectonics which creates mountains and volcanoes.

Hydrosphere covers all water on Earth, including oceans, lakes, glaciers, and water vapor, and is tied to the water cycle.

Less than 1% of the Earth's water is usable by humans, making water an extremely valuable resource.

Biosphere includes all life forms on Earth, from microbes to large animals, and is interconnected with the other three systems.

Humans' dependence on the atmosphere for oxygen, the hydrosphere for water, and the lithosphere for resources is emphasized.

Human activity, such as overuse of resources and pollution, has significant impacts on the Earth’s systems.

The four Earth systems—atmosphere, lithosphere, hydrosphere, and biosphere—are all interconnected and impact one another.

Transcripts

[Music]

Hey mr. Rochelle again alright so in

this lesson we're going to start looking

at the physical geography

of the earth and when we begin to look

at physical characteristics we find

there is a lot to it there are oceans

there's mountains those rivers or as

weather and climate vegetation and so

much more to help explain these physical

characteristics we can use something

known as the for earth systems the for

earth systems our atmosphere lithosphere

higher sphere and the biosphere now just

by looking at these terms we can see

they have all one thing in common they

are described as spheres now normally we

think about a sphere is being shaped

like a ball but the word sphere here

means a section of the world that is

unified by a particular characteristic

however if you want to think about it

it's just basically a ball or a circle

that we're putting all these

characteristics into that would work too

and we're also going to see that not

only does each sphere have its own sub

components but all of these spheres

interconnect with each other

so let's begin by looking at the

atmosphere the atmosphere describes the

envelope of gases around the earth and

the very word Atlas actually means

vapour or a gas so if you look at this

footage from the International Space

Station you can actually see that

atmosphere of surrounding the earth and

you can also see that the atmosphere has

different layers now the highest layer

is the exosphere which is anywhere

between 600 to 6000 miles above the

earth now as we go down from the

exosphere we go to the thermosphere the

mesosphere and then we get down to the

stratosphere that is anywhere between 9

and 30 miles above us but in the

stratosphere is incredibly important

because 90% of all the ozone gases in

the atmosphere is found in the

stratosphere and why this is important

because it is ozone which actually

absorbs and scatters the ultraviolet

radiation from the Sun and without this

ozone layer there would be no life on

Earth then there is the troposphere

which is what we lived in stretching

from the ground to about 9 miles high

now while this is the thinnest layer it

also contains 75% of all the atmospheres

mass now altogether all the gases of the

atmosphere actually weighs an incredible

five million billion tons but it's

distributed around the entire Earth

now the average weight actually pressing

down on you is 15 pounds for every

square inch of your body but you don't

notice it because well it's normal for

us we've always had that around us now

the atmosphere is important this is

pretty easy to understand has each

breath you take you're inhaling and

exhaling this atmosphere and without the

atmosphere we would not have the oxygen

we need to live but only 21% of the

atmosphere is actually oxygen 78% is

nitrogen this is why scuba divers may

get something called decompression

sickness or what is normally known as

the bends see as a diver descents the

nitrogen they breathe dissolves into the

muscle tissue as the water pressure

increases but unlike oxygen the body

doesn't use up this nitrogen so the

diver comes back up to the surface these

nitrogen bubbles will expand kind of

like a soda pop when you open it this

can cause pain brain damage and even

death while well-trained divers know how

to avoid this from happening it points

to the fact that most of our atmosphere

is actually made up of nitrogen now the

remaining 1% of the atmosphere is made

up of other gases such as argon helium

methane and carbon dioxide carbon

dioxide is the reason there is about 720

Giga tons of carbon in our atmosphere

even though it represents only one for

one hundreds of a percent of the

atmospheres gases it is this carbon from

the atmosphere that is the backbone of

all life on Earth through something

known as the carbon cycle now the carbon

cycle is this transfer of carbon between

the atmosphere animals trees rocks in

the oceans when we breathe we exhale

carbon dioxide about one kilogram a day

trees and plants will pull in carbon

dioxide from the atmosphere through

photosynthesis and then they will use

this carbon to be able to create glucose

in order to grow the oceans also absorb

carbon dioxide were marine plants such

as phytoplankton will turn this carbon

into organic matter no people and

animals may eat the plants which

reintroduces carbon into our bodies also

when trees and plants die they will

slowly begin to decay and decompose

returning carbon to the soil now this

gives fertility through the soil which

allows it to be able to absorb moisture

and provides the minerals that plants

need to be able to grow now some of the

carbon from the decaying plants and

animals on the land on the oceans will

come covered by more and more more soil

now speed forward several million years

and this process might find the carbon

be hundreds if not thousands of feet

below the surface now together with

chemical reactions pressure and heat

this carbon now becomes fossil fuels

such as oil and coal

today's oil comes from 300 million years

ago and the result of the deposition of

marine animals such as the final

cleaning that we talked about earlier

now when we burn these fuels we releases

carbon into the atmosphere and the

carbons continues in fact it is the

burning of fossil fuels that most

scientists believe is the reason why

carbon dioxide levels in the atmosphere

have increased since the Industrial

Revolution and may be a contributing

factor to the warming of the earth now

the atmosphere describes the gases above

the earth but what about the ground

itself litho in the term lithosphere

comes to the word which means rock so

when we talk about the lithosphere in

terms of the four earth systems we're

talking about all the rock in the world

this includes the Earth's core the

mantle and the rocky crust that we live

on it also includes the soil from which

trees and plants grow the crust and

upper mantle create continents and

oceanic plates which move around and

create the world's mountains and

volcanoes through something known as

plate tectonics in which we see both new

crust being created and old crust being

forced down below the earth's surface

the new crust is created by the

spreading of the ocean floors and by

volcanoes in fact an estimated 1 billion

tons of new crusts are created each and

every year but about the same amount of

crust is forced back down to the mantle

by a process known as convergent

subduction this is a process that is

shaped and reshaped the Earth's surface

for 3.2 million years then there are the

oceans and all the Earth's water in what

is described as the hydrosphere with

hydro meaning water but the hydrosphere

doesn't just describe the water we find

in oceans and lakes it also describes

the water we find frozen in the glaciers

and the water vapor we find in the

atmosphere in fact this exchange of

water with G the hydrosphere and

atmosphere forms the water cycle C the

water evaporates from the oceans of

lakes and lifts into the atmosphere as

water vapour does water vapour will

condense and fall to the ground as rain

or snow rain water either flows off into

rivers flowing back into the lakes and

oceans or it percolates into the soul

or provides the moisture for plants to

grow no plants grow and give off water

vapor through transpiration and along

with the water vapor that is a factory

from oceans and lakes the cycle

continues the water cycle now of the

Earth's over 300 million cubic miles of

water there is less than 3% that is

actually freshwater and of that

freshwater nearly 70% is trapped into

glaciers in the polar icecaps

so of all the water in the world less

than 1% is actually usable by us which

has made water an extremely important

resource which countries and nations

have actually fought over before last is

the biosphere which comes from the Greek

word bio which means life this includes

all the life in the world to include the

Tyus the microbes - the largest whales

in the ocean it also includes us in the

three previous systems I described how

each has a cycle well within the

biosphere we have the

[Music]

actually there's something called a life

cycle which biologists define as a Serie

of changes of life of organism think

about the cycle of a caterpillar turning

into a butterfly this is an example of a

life cycle but just as we see in other

Earth's systems the biosphere is

interconnected with the other three

systems animals are part of the carbon

cycle through the exhaling of carbon

dioxide and plant photosynthesis plants

give off a water vapor as part of

transpiration and the water cycle and

while the bio store does not play a part

in either the creation or end of the

Earth's crust it does play a vital part

in the creation of soil through the

deposition of organic material we give

soil as fertility but probably the most

important thing to understand is the

biosphere is depend upon these three

other systems for is survival without

oxygen or ozone in our atmosphere we

would not be able to survive we are

dependent upon water for the drink given

for agriculture the lithosphere not only

gives us the soils we need to be able to

grow our crops but we - resources out of

the ground to be able to build our

societies and as humans we also have a

profound impact upon each of these other

systems we can overuse and deplete these

resources such as water and through the

pollution we can have long-lasting

impacts to both the atmosphere in the

hydrosphere together the four systems

are integrated and impact each other in

major ways and in this course we'll talk

about how the interaction of these earth

systems have all had an impact upon the

regions of the world so until next time

keep on learning

[Music]