Download ERS 121 Study Guide for Exam 2 Lecture 11. From dinosaurs to

ERS 121 Study Guide for Exam 2
Lecture 11. From dinosaurs to wooly mammoths
1. When did the 3 step-like cooling events of the Cenozoic occur?
2. What was the overall trend in global temperature since the Eocene (52 million
years ago)?
3. Has there always been a greenhouse effect on Earth?
4. The onset of northern hemisphere glaciation in the late Cenozoic was at about
_________ million years ago.
5. Name two possible causes for the global cooling trend that has occurred since 50
million years ago.
6. What is the approximate shape of the near 100,000-year glacial cycle that
dominates the past 900,000 years?
7. The dominant cycle of climate change over the last 900,000 years is about
___________ thousand years.
8. Snow that falls in Antarctica is _____________ (depleted or enriched) in
oxygen-18.
9. During the last million years, how frequent were interglacials?
10. How many natural isotopes of oxygen are there?
11. At the last glacial maximum (LGM) the world ocean was _____________
(depleted or enriched) in oxygen-18.
12. Between 2.5 and 1 million years ago what was the dominant cycle of climate
change is about ___________ thousand years.
Lecture 12. The emergence and spread of humans
1. Given a map of the world, be able to label the continents with their name and the
number of years ago that humans first arrived.
2. What is important about the African rift from the perspective of human evolution?
3. What was the first hominid species to spread out of Africa? When?
4. What were the two major migrations of humans out of Africa? When?
5. When and where did hominids arise?
6. What are australopithecines?
7. What are robust australopithecines?
8. What are the two types of australopithecines?
9. What are gracile australopithecines?
10. Name one species of gracile australopithecines?
11. Which came first, large brains or bipedalism?
12. Who is Homo erectus?
13. When did humans first arrive in Australia?
14. Where did modern humans arise?
15. About when did modern humans arise?
Lecture 13. Abrupt climate jumps
1. What is a Dansgaard/Oeschger event?
2. Has the current intreglaciation been marked by abrupt climate changes similar to
those of the last glaciation? Why or why not?
3. The downward limb of the conveyor in the North Atlantic region can be disturbed
by massive inflow of fresh water. Name two ways by which such inflow can
occur.
4. What are Heinrich events?
5. What could have caused the abrupt, millennial-scale climate changes of the last
glaciation?
Lecture 14. Changes in sea level
1. Why is eustatic sea level rising at present?
2. Explain the difference between relative and eustatic sea level.
3. How do we know that eustatic sea level was 120 meters lower at the LGM?
4. How do we know that land was depressed under large ice sheets at the LGM?
Lecture 15. Greenhouse effect and global warming
1. What is a greenhouse gas.
2. List three greenhouse gases.
3. The most important greenhouse gas in Earth's atmosphere is _______________
4. With greenhouse gases at present-day levels, the globally averaged surface
temperature on Earth is approximately _____________ degrees Celsius.
5. Without greenhouse gases, globally averaged surface temperature on Earth would
be approximately _________________ degrees Celsius.
6. Everything else being equal, a gradual increase in atmospheric CO2 would most
likely bring about: (1) no change in global climate (2) a decrease in evaporation
from the earth’s oceans (3) a marked decrease in plant growth (4) an increase in
surface temperature
7. What has been the trend in the concentration of atmospheric CO2 during the 20th
century?
8. What is the present-day concentration of atmospheric CO2 in parts per million by
volume (ppmv)?
9. What was the pre-industrial concentration of atmospheric CO2 in parts per million
by volume (ppmv)?
10. What was the concentration of atmospheric CO2 at the LGM in parts per million
by volume (ppmv)?
Lecture 16. Origin of the Universe and the solar system
1. Who was Nicolaus Copernicus? What did he prove?
2. Who was Johannes Kepler? What did he do?
3. Who was Galileo Galilei? What did he do?
4. What shape is the orbit of Earth?
5. What was the "Big Bang"?
6. What is the geocentric theory?
7. What is the heliocentric theory?
8. The sun is an average main sequence star. What is the typical life span of this kind
of star?
9. Name three types of galaxies.
10. The age of the universe is approximately ________ billion years.
11. How do we know that the universe is expanding?
12. Earth is approximately _______ billion years old.
13. How many planets are in the solar system? List them.
14. By what process do stars generate energy?
15. What is the “redshift”? Lecture 17. Seasonality
1. Earth's axis of rotation is tilted relative to its orbital plane by ______ degrees.
2. When is the shortest day of the year in the northern hemisphere?
3. Why do seasons occur on Earth?
4. What is the Arctic Circle?
5. What is the Antarctic Circle?
6. What is the Tropic of Cancer?
7. What is the Tropic of Capricorn?
8. What is the shape of Earth's orbit when eccentricity is equal to zero?
9. How many times per year does the sun pass directly overhead at 10 degrees south
latitude?
10. How many times per year will the sun pass directly overhead at noon in Bangor,
Maine (latitude 45 degrees N)?
11. List three aspects of the geometry of Earth's orbit that vary on time scales ranging
from 20,000 to 100,000 years.
12. The eccentricity of Earth's orbit varies with a period of approximately
____________ years.
13. The precession of the equinoxes varies with a period of approximately
____________ years.
14. The tilt of Earth's axis of rotation varies with a period of approximately
___________ years.
Lecture 18. Monsoons
1. What is a monsoon?
2. Why are there monsoons?
3. Where is the largest monsoon system on earth?
4. What time of the year is dry in western Africa?
5. What time of the year is wet in northern Australia?
Lecture 19. El Niño / Southern Oscillation (ENSO)
1. In the western Pacific does sea level rise or fall during an El Niño event?
2. Is the Southern Oscillation Index (SOI) a measure of atmospheric or
oceanographic variability?
3. During an El Niño what happens to sea surface temperatures in the eastern
Pacific?
4. During a La Niña event does the thermocline in the eastern Pacific deepen or
shallow?
5. During an El Niño event do the trade winds strengthen or weaken?
6. During a La Niña event does equatorial upwelling in the eastern and central
Pacific strengthen or weaken?
7. During an El Niño event does equatorial upwelling in the eastern Pacific
strengthen or weaken?
8. What are the trade winds? Where are they located?
9. Why is the sea surface temperature off the coast of Peru cooler than that of the
western Pacific at the same latitude?
10. Why is the north coast of Peru a desert?
Lecture 20. Droughts, floods, & severe weather
1. Define drought.
2. Name two possible mechanisms that can cause a drought.
3. What is atmospheric blocking?
4. When was the "Dust Bowl"?
5. Name two types of floods.
Lecture 21. Paleoindians and the great mammal extinction
1. Who were the paleoindians? When and where did they exist?
2. When did paleoindians enter North America?
3. How did humans first get to North America?
4. When and where did paleoindians exist?
5. What is a Clovis point?
6. What is the overkill hypothesis for late Pleistocene extinctions, and what is the
evidence in support of this hypothesis?
7. Why did so many large animals disappear from the North American continent at
the end of the last ice age? On what evidence do you base your answer?
8. Outline the hypothesis that modern humans were responsible for the extinction of
many species of large mammals during the last ice age.