THE SPHERES OF THE EARTH. Tuesday, April 1, 2014. As you can see from the previous slides the earth is made up of a number of spheres, the most important are: The Atmosphere The Lithosphere The Hydrosphere The Biosphere. The many spheres of the earth:. Can you name them?.
Tuesday, April 1, 2014
As you can see from the previous slides the earth is made up of a number of spheres, the most important are:
Can you name them?
The main focus of physical geography is on the LIFE LAYER of the earth: a shallow zone of the lands and oceans containing most of the world’s organic life (also called Biosphere).
The Biosphere connects with all three.
Vertically, the habitable zone (the biosphere) surrounding the Earth is extremely restricted. The blanket of air extends to an altitude of about 30km and fades away into empty space. The living zone of the air is a layer only 5km high.
If you compare this to the radius of the earth it would be the earth being a regular sized peach and the living zone would be thinner than the fuzz.
On the surface of the earth, some areas are too dry, too wet, too cold, too hot or too rugged to support human life. The most uninhabitable areas on earth is Greenland, Antarctica and the Arctic.
The Atmosphere is the air we breathe. The Hydrosphere is the water of rivers, lakes and oceans, the moisture in soil and air, as well as the snow and ice of the cryosphere. The Biosphere is the habitat of all earthly life. The Lithosphere is the soil and bedrock that cover the Earth’s surface.
Planet Earth, by Gary Birchall (John Wilely and Sons)
Note: Yellow represents the energy coming from the sun. Orange represents what is absorbed and Red represents what is released back into space - sometimes called the albedo.
The earth either absorbs the energy and converts it into other types of energy like:
- Fossil Fuels
- Temperature and precipitation
- Winds and Pressure
- The Hydrologic Cycle (see picture next slide)
But today, we can no longer take the systems that make life possible on earth for granted. We have grown to an incredible size (6 billion). Our technology is constantly presenting new threats to the environment:
We must learn all we can about these factors that make up our life support systems. That is where Physical Geography comes in. We must prevent the destruction of the physical environment.
THE FUTURE OF THE EARTH IS AT RISK!
Let’s continue our understanding of the spaceship earth by introducing the earth. Let’s look at the earth’s basic dimensions and how we measure the earth and places on the earth.
Go to the slide show entitled: Intro_Earth