1. The Physical World

2. economies and resources: water scarcity
Introduction
economies and resources: water scarcity
Water is a basic need for all humans. Providing freshwater to support human activity is a significant challenge in drought-prone areas around the world. Agriculture, industry, and thriving population centers all depend on a reliable supply of safe, fresh water to support human endeavors.
Women and Water in the Sahel

3. Planet Earth

4. Our Solar System
Earth is part of our solar system, which is made up of the Sun and all the countless objects revolve around it. Our solar system’s center is the sun - a star, or ball of burning gases. About 109 times wider than Earth, the sun's enormous mass- the amount of matter it contains- creates a strong pull of gravity. This basic physical force keeps the Earth and other objects revolving in orbit around the sun.
Earth is part of our solar system, which is made up of the Sun and all the countless all the countless objects revolve around it. Our solar system’s center is the sun - a star, or ball of burning gases. About 109 times wider than Earth, the sun's enormous mass- the amount of matter it contains- creates a strong pull of gravity. This basic physical force keeps the Earth and other objects revolving in orbit around the sun.

5. Our Solar System There are eight planets in our solar system.
The planets vary in size with Jupiter being the largest. Earth ranks fifth in size, and Mercury is the smallest.
There are at least five dwarf planets in our solar system. Pluto used to be the smallest planet in the solar system until It is now classified as a dwarf planet. What criteria makes a planet dwarf?
The 4 inner planets are called terrestrial planets because they have solid, rocky crust.
There are eight planets in our solar system.
the planets vary in size with Jupiter being the largest. Earth ranks fifth in size, and Mercury is the smallest.
there are at least five dwarf planets, Pluto being the smallest planet in the solar system until It is now a dwarf planet. What makes a dwarf Planet?

7. Our Solar System
The four outer planets are called the gas giant planets. They are the most gaseous and larger in diameter.
Thousands of smaller objects - including asteroids, comets, and meteoroids - revolve around the sun.
a journey through our solar system
There are eight planets in our solar system.
the planets vary in size with Jupiter being the largest. Earth ranks fifth in size, and Mercury is the smallest.
there are at least five dwarf planets, Pluto being the smallest planet in the solar system until It is now a dwarf planet. What makes a dwarf Planet?

8. Getting to Know the Earth
The Earth is a rounded object that is slightly wider around the center than the top to bottom. Earth has a larger diameter at the equator - about 7,930 miles - than from pole to pole, but the difference is less than 1%. With a circumference of about 24,900 miles, Earth is the largest of the inner planets in the Solar System.
The surface of the earth is made up of water and land. About 70% of our planet's surface is water. The water areas of the earth, including oceans, lakes, rivers, and other bodies of water is called the hydrosphere.
The uppermost layer of the Earth that includes the crust, continents, and ocean basins is called the lithosphere.
the air we breathe is part of the Earth's atmosphere, a thin layer of gases that surround the Earth.
The part of Earth where life exists is the biosphere. All people, animals, and plants live in the biosphere.

9. Getting to know the Earth
The air we breathe is part of the Earth's atmosphere, a thin layer of gases that surround the Earth.
The part of Earth where life exists is the biosphere. All people, animals, and plants live in the biosphere.
Landforms are natural features at the surface of the Earth lithosphere. Landforms contain rivers, lakes, streams, mountains, etc.
The continental shelf, part of the continent that extends out underneath the ocean, is an underwater extension of the coastal plain.
the continental shelf, part of the continent that extends out underneath the ocean, is an underwater extension of the coastal plain.
great contrast exist in the Heights in the depth of the Earth's surface. The highest point on Earth is in South Asia at the top of Mount Everest which is feet above sea level. The lowest dry land point at 1312 feet below sea level is the shore of the Dead Sea in Southwest Asia. The Earth's deepest known depression lies under the Pacific Ocean in the Mariana Trench, an arrow, underwater canyon about feet deep

10. Getting to know the Earth
Great contrast exist in the heights and the depth of the Earth's surface. The highest point on Earth is in South Asia at the top of Mount Everest which is 29,028 feet above sea level. The lowest dry land point at 1,312 feet below sea level is the shore of the Dead Sea in Southwest Asia. The Earth's deepest known depression lies under the Pacific Ocean in the Mariana Trench, a narrow, underwater canyon about 36,198 feet deep.
the continental shelf, part of the continent that extends out underneath the ocean, is an underwater extension of the coastal plain.
great contrast exist in the Heights in the depth of the Earth's surface. The highest point on Earth is in South Asia at the top of Mount Everest which is feet above sea level. The lowest dry land point at 1312 feet below sea level is the shore of the Dead Sea in Southwest Asia. The Earth's deepest known depression lies under the Pacific Ocean in the Mariana Trench, an arrow, underwater canyon about feet deep

12. Forces of Change

13. Earth’s Surface
For hundreds of millions of years, the surface of the Earth has been in motion. Pressures generally build up slowly inside the earth and are then released and sudden events like volcanic eruptions and earthquakes occur. Other forces that change the earth, such as wind and water, occur on the surface.

14. Earth’s Surface
The Earth is composed of three main layers the core, the mantle, and the crust.
The core is the innermost layer of the Earth made up of a super hot but solid inner core and a super hot liquid outer core
The mantle is a thick middle layer of the Earth's interior structure consisting of hot rock that is dense but flexible
The crust is an outer layer of the Earth, a hard rocky shell forming Earth’s surface
The Earth is composed of three main layers the core, the mantle, and the crust.
The core is the Innermost layer of the Earth made up of a super hot but solid inner core and a super hot liquid outer core
the mantle is a thick middle layer of the Earth's interior structure consisting of hot rock that is dense but flexible
the crust is an outer layer of the Earth, a hard Rocky shell for me North surface

15. Earth’s Surface
The continental drift is the theory that the continents were once joined and then slowly drifted apart. Prior to the continental drift the name of the supercontinent was?
Continental Shuffle
Plate tectonics is the term scientists use to describe the activities of continental drift and magma flow, which create many of the Earth’s physical features.
Plate Tectonics
The Earth is composed of three main layers the core, the mantle, and the crust.
The core is the Innermost layer of the Earth made up of a super hot but solid inner core and a super hot liquid outer core
the mantle is a thick middle layer of the Earth's interior structure consisting of hot rock that is dense but flexible
the crust is an outer layer of the Earth, a hard Rocky shell for me North surface

16. Earth’s Surface
Magma - molten rock that is located below the Earth’s surface
Scientists have yet to determine exactly what causes plate tectonics.

17. Internal Forces of Change
Earth’s surface has changed greatly over time. Scientists believe that some of these changes come from forces associated with plate tectonics.One of these forces relates to the movement of magma within the Earth. Others involve movements that can fold, lift, bend or break the solid rock at the Earth’s crust.

18. Internal Forces of Change
Colliding and Spreading Plates
Mountains are formed in areas where giant plates collide. For example, the himalaya mountain ranges in South Asia were thrust upward when the Indian landmass drifted against Eurasia.
Mountains are also created when the oceanic plate collides with the continental plate. This is called subduction - a process by which oceanic plates dive beneath continental plates, often causing mountains to form on land.
Subduction

19. Internal Forces of Change
Colliding and Spreading Plates
Accretion - slow process in which an oceanic plate slides under a continetal plate, creating debris that can cause continents to grow outward. This makes mountains underwater
New lands can also form when 2 oceanic plates converge. It is called spreading, process by which magma wells up between oceanic plates and pushes the plates apart. This often makes islands and island chains

20. Internal Forces of Change
Folds and Faults
Moving plates sometimes squeeze the Earth’s surface until it buckles
Fold - a bend in the layers of rock, sometimes caused by plate movement
Fault - a crack or break in the Earth’s crust. A famous fault is the San Andreas fault in California
Faulting - a process of cracking that occurs when the folded land cannot be bent any further.

21. Internal Forces of Change
Earthquakes and Volcanoes
Sudden, violent movements of the lithosphere along fault lines are known as earthquakes. During a severe earthquake in Alaska in 1964, a portion of the ground lurched upward 38 feet.
Earthquakes often occur when plates meet. Tension built up along fault lines as the plates stick. The strain eventually becomes so intense that the rocks suddenly snap and shift. This movement releases stored up energy along the fault.
Disastrous earthquakes have occurred in Kobe, Japan; in the US cities of Los Angeles and San Francisco; near the Indonesian island of Sumatra; and in Oaxaca, Mexico. These places are located along the ring of fire, one of the Earth's most earthquake-prone areas on the planet.
Ring of Fire
Sudden, violent movements of the lithosphere along fault lines are known as earthquakes. During a severe earthquake in Alaska in 1964, a portion of the ground large upward 38 feet.
Earthquakes often occur when plates meet. Tension built up along fault lines as the plates stick The Strain eventually becomes so intense that The Rock suddenly snap and shift. And this movement releases stored up energy along the fault.
disastrous earthquakes have occurred in Kobe Japan semicolon in the US cities of Los Angeles and San Francisco semicolon near the Indonesian island of Sumatra semicolon and a no oxaca Mexico. These places are located along the ring of fire, one of the Earth's most earthquake-prone areas on the planet.

22. Internal Forces of Change
Earthquakes and Volcanoes
Volcanoes are mountains formed by lava or by magma that breaks through the Earth's crust.
Volcanoes often rise along plate boundaries where one plate plunges beneath another as along the Ring of Fire. In such a process, the rocky plate melts as a dives downward into the hot mantle. If the molten rock is too thick, its flow is blocked and pressure builds. A cloud of ash and gas spews forth, creating a funnel through which the red hot magma rushes to the surface.

23. External Forces of Change
External forces, such as wind and water, also change the Earth's surface. Wind and water movements involve two processes
Weathering is a chemical or physical process that breaks down rock into smaller pieces
Erosion is the movement of weathered rock material by wind, glaciers, and moving water
External forces, such as wind and water, also change the Earth's surface. When and water movements involved two processes
weathering is a chemical or physical process that breaks down rock into smaller pieces
erosion is the movement of weathered rock material by wind, glaciers, and moving water

24. External Forces of Change
Weathering and Erosion
Physical weathering occurs when large masses of rocks are physically broken down into smaller pieces. For example, water seeps into the cracks of a rock and freezes, expanding and causing the rock to split.
Chemical weathering changes the chemical makeup of rocks. For example, rainwater that contains carbon dioxide(what kind of rain is this?) from the air easily dissolves certain rocks such as limestone
Another cause of erosion is glaciers. Glaciers are large body of ice that moves across the surface of the Earth
Moraines - a pile of rocky debris left by melting glaciers
Physical weathering occurs when large masses of rocks are physically broken down into smaller pieces. For example, water seeps into the cracks and a rock and freezes, expanding and causing the rock to split.
Chemical weathering changes the chemical makeup of rocks. For example, rainwater that contains carbon dioxide from the air easily dissolves certain rocks such as limestone
another cause of erosion is glaciers. Glaciers are large body of ice that moves across the surface of the Earth

25. The Water Cycle

26. The Water Cycle The Water Cycle
The total amount of water on Earth does not change, but it is constantly moving - this is called the water cycle, regular movement of the Earth’s water from the oceans to the air to the land and finally back to the oceans.
The Sun drives the water cycle , this process is called evaporation, the process of converting liquid into vapor, or gas
The process of excess water vapor changing into liquid water when warm air cools
Moisture that falls to the Earth as rain, sleet, hail, or snow is considered precipitation
The amount of water that evaporates is approximately the same amount that falls back to Earth.

27. The Water Cycle Bodies of Salt Water
Almost all the water on earth is salt water
Seas, gulf, and bays are bodies of salt water smaller than oceans
Although 97% of the world’s water is found in oceans it is way too salty for drinking, farming, or manufacturing. The world’s growing population requires an abundance of freshwater that we do not have. So, efforts are concentrated on Desalinization, the removal of salt to make is usable for drinking and farming.

28. The Water Cycle Bodies of Freshwater
Only 3% of the Earth’s total water supply is freshwater.
More than ⅔ is frozen as glaciers and ice caps
⅙ is beneath the Earth’s surface
Lakes, streams, and rivers contain less than ⅓ of 1 % of Earth’s freshwater
Groundwater is water located underground within the Earth that supplies wells and springs
Aquifers is underground water-bearing layers of porous rock, sand, or gravel