Inside the Earth – Third Rock from the Sun

• The Earth is not a solid rock, but instead consists of layers

• Inner Core – solid iron and nickel• Outer Core – liquid iron and

nickel (contains the basis for our magnetic field – that protects us from most forms of solar radiation)

• Mantle – semisoft melted rock• Crust – thin cooled skin that

“floats” on the mantle – contains cracks and moves

• Movement of the crust causes earthquakes and volcanoes

Plate Tectonics• The Earth’s crust is

broken into plates• The plates move along

the flowing mantle in different directions

• Pressure between the plates builds up until it is released by an earthquake

• Ring of Fire – hundreds of volcanoes around the Pacific Rim where the Pacific plate interacts with other plates

Air and Water – Necessary for Life on Earth• Air– Contained with the Earth’s atmosphere – a layer of gasses that

surround the planet– Actually composed of many different types of gasses

• Nitrogen – about 78% (essential for development of proteins)• Oxygen – about 21% (essential for respiration)• Others – about 1% combined

• Water– 97% of the water on Earth is found in the Ocean – it’s salty– Only 3% of the water on Earth is fresh

• Mostly found in the polar caps and glaciers (huge ice sheets found on mountains, Antarctica and Greenland)

• Great deal is underground – sometimes miles deep• Very little (0.3%) is at the surface (mostly lakes) and therefore useable by

living organisms – very important to conserve and keep clean what we have

Water Cycle

http://www.youtube.com/watch?v=dkELENdZukI

Wind and Water help keep the earth from overheating

• Wind– Hot air rises – so air in the tropics

rises and is carried towards the polar regions

– Cold air in the polar regions sinks to the surface and flows towards the tropics

– Cold air – can not hold much water vapor

– Warm air – can hold more water vapor

– Wind happens when the air flows from the areas where it’s sinking to areas where it’s rising

– The Earth’s rotation helps drive wind direction

• Water– Warm water is lighter

than cold, dense water– Water in tropical regions

flows slowly towards the polar regions

– Cold water in the polar regions sinks to the bottom of the ocean and flows south towards the tropical regions, where the cycle begins all over

Chapter 2.2Natural Resources

• Natural resources are anything from the Earth that people use in meeting their needs for– Food – Clothing – Shelter

• Examples;

Chapter 2.2Types of Natural Resources (raw material)

• Recyclable Resources – Recycle naturally through the earth itself– Water, carbon, oxygen and nitrogen– Can refer to items that can be reused without replacing the resource

• Aluminum • Plastic• Paper

• Renewable Resources– Resources that can be replaced by man– Wood – trees can be replanted– Biodiesel and ethanol – crops can be replanted

• Nonrenewable Resources– Can not be replaced– Important to conserve and use wisely -- they’re no longer being created– Oil, natural gas, coal, minerals

Energy Resources• Energy is needed

for every living thing

• Fossil Fuels – Include coal,

natural gases, petroleum (oil byproduct)

• Problem? Not everyone has oil I their back yard– Saudi Arabia and

Mexico have large amounts of oil but other countries like the US and China have more natural gas and coal

New Supplies Needed!!• 1979 OPEC raised the price of oil– What was the outcome?• Gas prices went up • Countries with limited sources of oil had to buy at

an increased price raising their asking price for products– A global problem?

• EVERYONE NEEDS OIL– THE SEARCH IS ON!!

Chapter 2.3Climate vs. Weather

• Climate– Long term average weather in

any one place or region– “the climate in Jamaica is

tropical”– Largely affected by wind

patterns, water currents and major landforms

– Changes take place over years or even millennia

• Weather– Day to day changes in the air

in terms of precipitation and / or temperature

– “It’s 90 degrees today”– Affected by the movement

of storms around the planet– Changes rapidly over a few

days

Broad Types of Climate on Earth• Tropical

– Low latitudes around the Equator– Generally hot, wet and sunny– Rain forests dominate

• Dry– Different places around the Earth – generally on the opposite side of mountain ranges from wind

flow– Little to rain with sandy soil– Sparse to no vegetation

• Moderate– Found in the middle latitudes (like Connecticut)– Temperatures and rainfall are generally moderate enough every year to promote agricultural

production• Continental

– Hot summers and bitterly cold winters– Generally drier than moderate climates– Large grasslands in some areas and forests in others

• Polar– Found in high latitudes– Cold all year round– Vegetation includes low shrubs, mosses– Very little life found in these regions

Map showing relative positions of the Gulf Stream and Labrador Current