1. RMS TIME IS FOR READING

2. Good Day Everyone! Today is Tuesday 9/19/17
Announcements
-Makeup Lab today at lunch/HAC
-No School Thursday & Friday
Agenda:
-Warm Up
-Notes Principle of Horizontality
-Antartica’s Climate Secrets

3. Warm Up- write out the question and answer
Which of the following can cause erosion
Falling leaves
Growing grass
Flowing water
Rising temperatures
The freezing and thawing action of water in a rock affects it by:
Eroding away the material
Mechanical weathering of the rock
Depositing more minerals
Chemical weathering of the rock

4. Principle of Horizontality
What is it?
Let’s explore: Click on the link below to Law of Superposition and Principle of Horizontality.

5. Principle of Horizontality
The principle of Horizontality tells us that when things are formed in nature, they form in horizontal layers.
The youngest will be on the top and the oldest will be towards the bottom.

6. Examples: Real life examples where Scientists use this principle:
Tree Rings
Ice Cores
Sedimentary Rock Layers

7. Learning about the Earth
All of these things tell us how the Earth’s Climate has changed over time

8. Dendrochronology
Name at least one way that studying tree rings can help us today?

9. Limitations to analyzing tree rings - Dendrochronology
Trees in the temperate zone only record the growing season, so the winter season, no matter how dramatic, will not be seen in the ring record.
Trees in tropical regions grow year round and therefore show no real obvious annual growth rings (climate data from equatorial areas is difficult to piece out and use).
Trees do not grow in all places on Earth,
No trees in
polar regions,
high in the mountains
in the ocean

10. Tree Rings Show us how old the tree is
Tell us about the Temperature and Climate from the past
Wider rings= lots of rain and warmer temperatures
Narrower rings= less rain and colder temperatures

11. Ice Cores
An ice core is: a cylinder of ice removed from an ice sheet, or glacier

12. Reading Ice Cores

13. Ice Cores
Different amounts of dust, ash from volcanoes,carbon dioxide and argon show changes in Earth’s atmosphere

14. Ice Cores
Ice Cores tell us the amount of gases in the Earth’s atmosphere over time
Ice cores have air bubbles trapped in the ice that can be analyzed to see how Earth’s atmosphere has changed

15. Bubbles in the ice What we can learn Bubbles = gas trapped in the ice
Ex: Argon, Carbon Dioxide
If High CO2 found, it means the Earth’s temperature was higher (warmer)

16. Ash and Dust What we can learn:
Increases in dust and ash in the ice show volcanic eruptions.
We can infer that the eruption caused the Earth’s temperature to lower because the Volcanic ash blocks the sun.

17. Why does the Earth get colder after big volcanic eruptions?

18. These things block the sun from reaching earth!

19. Clouds of ash can cover entire continents!

20. Antartica’s Climate Secrets

21. Exit Ticket
You are walking through the woods behind Randolph. You notice a tree that was cut down. Looking at the cross- section of the tree, what will you be able to discover about the tree?