Download General World Cultures Chapter 2- Physical Geography glacier

General World Cultures
Chapter 2- Physical Geography
glacier- a huge, moving mass of ice
erosion- the wearing away of the Earth’s surface by wind or water
delta- a flat, sandy area where a river enters an ocean
plain- a flat landform
plateau- a high, flat landform
map projection- a way to draw the curved areas of the Earth on a flat surface
tropical- related to regions near the equator; a tropical climate is warm and moist
fossil fuel- coal, oil, or natural gas that formed over millions of years from the
remains of plants and tiny animals
renewable resource- a resource that can be replaced as it is used
nonrenewable resource- a resource that cannot be replaced by natural resources
or is replaced extremely slowly
* The Earth is not just a solid ball. It has three separate layers: the crust, the mantle,
and the core.
* The crust is a thin layer of rock, sand, and soil. It covers the Earth like a skin and
even lines the floor of the oceans.
* Below the crust is a thick layer of rock called the mantle. The outer part of the
mantle is melted but deeper inside it is solid.
* At the center of the Earth is the core, which is made up of two metals: nickel and
iron. In the outer core the metals are more fluid, but the very heart of the Earth is
solid.
* The inside of the core is a very busy place. Melted rock and other materials are
always flowing and rubbing together. This activity builds up heat and pressure that
causes movements in the crust. Sometimes, these movements can be felt as
earthquakes. Mountains and volcanoes are created and formed by forces deep in
the Earth. Most of the changes happen too slowly for people to notice. A volcanic
eruption, however, causes sudden change. Forces deep within the Earth, then, do
affect life on the surface. There is no way to stop these forces.
The Earth’s Surface
* Water covers 70% of the Earth. Therefore, only 30% of the Earth’s surface is
visible land. The water is in oceans, lakes, rivers, streams, ponds, and glaciers.
Water can also be found underground.
* The oceans and seas hold most of the water on the planet. This water is salty, and
we cannot drink it or use it for farming. Ocean water evaporates, however, and turn
into water vapor. Most of the salt stays behind, and the water vapor becomes part
of the air. Wind carries the water vapor over the land, where it may drop back to
the Earth as rain or snow. In time, the water flows back to the sea. This process is
known as the water cycle.
* The atmosphere is the layer of air around the Earth. It is about 1,000 miles thick.
It is made up mainly of two gases- nitrogen and oxygen- along with small amounts
of other gases.
* Water and air are always changing the surface of the Earth. Wind, ice, and flowing
water break down rocks. We call this process weathering. Wind and water also
carry away bits of rock and soil in a process called erosion. For example, through
erosion, a river may wash soil downstream. The soil ends up in a delta.
* Weathering and erosion shape the Earth’s surface. They wear mountains down to
hills and create valleys and canyons. The create plains and plateaus.
Complete the Landforms and Waterbodies Diagram Study on page 17.
Map Projections
* The Earth, shaped like a ball, has a curved surface. A globe is used to represent this
curved surface. Suppose you could remove the outer layer of this globe. Could you
smooth it out to make it flat like a map? Not quite. It would stretch and split in
many places.
* We are going to try an experiment. You will try to cover a round object using a flat
piece of paper. Write down your experiences on the piece of paper afterwards.
* You can see the problem that mapmakers face when they draw maps of the Earth.
A flat map cannot really show the curved surface of the Earth. That is why
geographers invented map projections.
* There are many different kinds of map projections. Each one shows a different
way to draw the curved areas of the Earth on a flat surface. However, all map
projections have some distortion. Some of these maps change the shapes of
continents or make their sizes look incorrect. In some map projections, the
distances between places look wrong. Some of these maps do not accurately show
directions (north, south, east, and west). The distortions are more noticeable on
maps that show larger areas. A map of the world has much distortion. A map of
your town would have almost none.
* A Mercator projection shows the true shapes of continents and islands. To make
the shapes correct, a Mercator projection stretches the lines of latitude apart. As a
result, the map does not show the true sizes of the landmasses. The farther away a
landmass is from the equator the greater the distortion. However, a Mercator
projection map is a good kind to use for travel on the ocean because it shows
directions accurately.
* Most maps in geography books are based on the Robinson Projection. This type of
projection map shows only small distortions. Only the landmasses near the South
Pole and North Pole look distorted.
Complete the Geography In Your Life Making Maps on page 19.
Rotation and Revolution
There are nine planets in the solar system:
My
Very
Easy
Method
Speeds
Up
Naming
Planets
Complete the webquest and accompanying worksheet at the following address:
http://teach.fcps.net/trt8/SolarSystem/Planets.htm
All of the planets travel around the sun. The Earth is the third planet in orbit away
from the sun. It takes a year for the Earth to make a full trip, or revolution, around
the sun.
* Revolution is one way in which the Earth moves through space. The Earth also
spins on its axis in a motion called rotation. The Earth makes one complete
rotation in 24 hours. However, the Earth’s axis does not point straight up and down.
It is slightly tilted.
* During some months, this tilt aims the North Pole a little towards the sun. In these
months, the sun shines directly on the Northern Hemisphere for more hours of each
day. These are the summer months in the Northern Hemisphere. In the Southern
Hemisphere, these are the winter months, because the South Pole is tilted away
from the sun.
* During the summer months in the Southern Hemisphere, the South Pole is tilted
towards the sun. When neither pole is tilted towards the sun, it is spring or fall. The
Earth’s tilt and its revolution together cause the changing seasons.
Complete the Geographer’s Tool Kit Understanding Latitude and Longitude on pg. 21
Climate Around the World
* The weather changes every day. Describe the weather outside today. _______________
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One day it might be warm and sunny, and the next day it might rain. The weather in
any one place follows a general pattern, however. For example, Denver, Colorado,
can expect some snowfall each winter. Los Angeles, California, can expect warm, dry
winds every fall.
* Why is climate different from place to place? ___________________________________________
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Three main factors shape climate. Latitude is one factor. The closer a place is to the
equator, the warmer it tends to be. Another factor is elevation. In general, the
higher above sea level a place is, the cooler it is.
Complete The World: Climate Regions on page 22
Finally, the ocean (an other large bodies of water) plays a part. The temperature of
the ocean does not change easily. When cold air blows over the ocean, the air
warms up. When hot air blows over the ocean, the air cools down. Therefore, it is
the ocean that prevents the extremes of great heat and cold. Therefore, it is the
ocean that prevents the extremes of great heat and cold. That is why places near the
ocean tend to have milder climates than inland areas.
* Some geographers divide the Earth into five climate regions. In the far north and
south are the polar regions. Near the poles and the middle of continents are the
cool/moist regions. Closer to the equator and near oceans and seas are the
warm/moist regions. Here and there are deserts that have a dry climate. Along
the equator is the hot, rainy tropical climate region.
Using the Earth’s Resources
* Anything we use from the Earth is considered a natural resource. Water is a
natural resource. Air is another. Without these two natural resources, nothing
could live. The plants and animals that we eat are resources. So are rocks, minerals,
soil, fossil fuels, and many other things.
* Some resources can be replaced as they are used. For example, when we cut down
trees for lumber, we can plant new ones to replace them. Trees, then, are
renewable resources. Some resources were formed millions of years ago, such as
fossil fuels like oil, natural gas, and coal. They cannot be replaced quickly. These are
nonrenewable resources.
* The Earth’s resources are spread out unevenly. In desert regions, for example,
fresh water is scarce. Without water, food is hard to grow. People in these areas
may have to trade the resources they have to get food. Most people depend on trade
to get at least some of the resources they need. Many desert regions are rich with
oil.
* In the U.S., most people work in factories and businesses. A lot of natural
resources are needed to support this way of life. Factories, power plants, and cars,
use a lot of energy. Much of that energy comes from burning fossil fuels.
* However, we may soon run out of fossil fuels. Furthermore, burning these fuels
does damage to the environment. Cars, factories, and power plants put harmful
smoke and gases into the air. Over the years, the air around the world has become
dirty and is killing some of our forests.
* The smoke and gases have affected the atmosphere high above the Earth, too. The
damaged atmosphere may be letting in more of the sun’s harmful rays, which could
change the climate of the Earth. Problems such as these are of interest to
geographers.
Complete Global Issues The Ozone Layer on page 25