7th grade Chapter 2 Sections 2 &3 Notes

Here are the notes for the next 2 sections. Please do not forget to read Section 3 as well.

Friday we will talk quickly through section 3 watch a video clip and then play a review game. Please be ready to play. It will not be fun if you do not know the material.

Mr. Clark

Forces Shaping Earth
Chapter 2
Section 2
Understanding Earth
• Core- sphere of very hot metal at the center of the Earth
• Mantle- thick hot rock layer around the core
• Crust- thin rock and mineral layer around the mantle
• All layers are “floating” on each other
Water and Air
• Less than 30% of the Earth’s crust is land
• 97% of Earths water is in the oceans
• Most fresh water is frozen in the polar ice caps
• Earths atmosphere contains miles of layers of gasses
• Contains oxygen, carbon dioxide and other important gasses
Landforms
• Mountains- raise more than 2000 feet above sea level. Wide at the bottom and narrow at the top
• Volcano- type of mountain
• Hills- less than 2000 feet, with rounded tops and less steep than a mountain
• Plateau- large mostly flat area that rises above the surrounding land. At least one side is steep
• Plains- large areas of flat gently rolling land
Forces inside Earth
• Magma- soft nearly molten rock
• Lava- molten rock
• Plates- blocks of Earth’s crust
Volcanoes & Earthquakes
• Fault- cracks in the Earth’s crust
• when 2 fault lines come together, pull apart or rub against one another, earthquakes happen
Forces on Earths Surface
• Slower processes happen on the surface
• Weathering- process that breaks down rocks into tiny pieces
– Ice, water, and lichens cause weathering
• Erosion- removal of small pieces of rock by water, ice or wind (wearing down)
• Removed material is moved downstream forming plains regions
This is the End of Section 2…………………below is Section 3. Please be sure to read this section as well as copying the notes.

Climate & Weather Weather- conditions of the air and sky from day to day
 Precipitation- water that falls to the ground: Rain, snow, sleet, hail
 Climate- average weather over many years.

Air currents are also called Belts or Cells

Water Cycle
Evaporation- Condensation- Cloud Formation- Rain- Flows into ground or water systems- Repeat

Oceans and Climate
 Oceans spread Earth’s heat
 Equatorial region would overheat
 Warm water flows away from Equator
 Cold flows towards Equator

Cooling and Warming Effect
 Water takes longer to heat than land
 Water takes longer to lose its heat than land
 Coastal or lakefront land is warmer than inland

Raging Storms
 Cyclones- intense wind and rain that form over the oceans in the Tropics
 N.H.- Hurricanes/S.H.-Cyclones
 Tornadoes are funnels of wind
 Formed around low pressure areas