The Great Oxygenation Event is called this due to releasing ________due to _______ about ______ years ago.

Question

2. Define feedback in a system & give an example.

:
3. ________ __________- Earth’s orbit changes from circular to slightly oval on a 100,000-year cycle. Earth has a _____ that varies 22-24 degrees over 40,000 years.

4. Circle the correct statement:
The Earth wobbles on its axis like a toy top toward and away from the sun, about every 26,000 years.
The Earth flings around its axis like a slingshot around the sun, about every 26,000 years.

5. ___________ _________ _________ are used as evidence of long term cycles of climate change on Earth.

6. Match the Cause & Effect.

Reduction in methane produced lower temps & higher glacier formation
A.

Increased temperatures due to Milankovitch Cycles caused glaciers to melt
B.

7. Scientists believe that the Milankovitch Cycles explain why Earth’s climate has fluctuated between __________and _________periods.

8. Match the correct time periods to the definition.

Interglacial Period
a period in Earth’s history marked by prolonged low global temperature
*Most recent ended ~11,500 years ago

Glacial Period
a period in Earth’s history marked by prolonged high global temperature

9. _______- system of measuring and describing quantities

10. Circle = True or False
Carbon dioxide levels since 1860 have reached the highest levels in recorded history.

Answer 1

1. The Great Oxygenation Event is called this due to releasing oxygen due to photosynthesis about 2.4 billion years ago.

2. Feedback in a system refers to the process where the output of a system influences its own operation. For example, in climate systems, increased global temperatures can lead to the melting of ice caps, which decreases the earth's albedo (reflectivity) and leads to further warming.

3. Milankovitch Cycles - Earth’s orbit changes from circular to slightly oval on a 100,000-year cycle. Earth has a tilt that varies between 22-24 degrees over 40,000 years.

4. Circle the correct statement: The Earth wobbles on its axis like a toy top toward and away from the sun, about every 26,000 years.

5. Paleoclimate records are used as evidence of long term cycles of climate change on Earth.

6. Match the Cause & Effect:

• Reduction in methane produced lower temps & higher glacier formation.
  A.
• Increased temperatures due to Milankovitch Cycles caused glaciers to melt.
  B.

7. Scientists believe that the Milankovitch Cycles explain why Earth’s climate has fluctuated between glacial and interglacial periods.

8. Match the correct time periods to the definition:

• Interglacial Period: **a period in Earth’s history marked by prolonged high global temperature (Most recent ended ~11,500 years ago)
• Glacial Period: a period in Earth’s history marked by prolonged low global temperature.

9. Quantification - system of measuring and describing quantities.

10. Circle = True or False: True - Carbon dioxide levels since 1860 have reached the highest levels in recorded history.