Geo 401

Front 1

What causes ice sheets to expand and ablate at timescales on the order of 10,000 to 100,000 years?

Back 1

Albedo

Front 2

2. What does it mean to “force” climate change

Back 2

factor outside of the earth's system causes climate change

Front 3

3. A single vertically explosive volcanic eruption can change climate in which of the following ways?

Back 3

It adds sulfur to the atmosphere which blocks reflects sunlight and causes global temps to drop

Front 4

4. How does silicate rock weathering affect climate over time?

Back 4

It traps CO2 which would lower the temperature

Front 5

5. What factors may have triggered the Cenozoic icehouse?

Back 5

The Tibetan Plateu formed, sink CO2 and other uplift and weathering. Seafloor spreading, volcanic eruptions

Front 6

3 timescales of climate change

Back 6

tectonic, orbital, and millenial

Front 7

early sun relative to today

Back 7

weaker sun in past

Front 8

snow ball earth

Back 8

600-700 mya, runaway albedo, detected through low latitude and low alt tillites

Front 9

What temp was Earth over most of its history relative to today

Back 9

warmer

Front 10

11. How were Milkanovich’s ideas of the timing and causes of orbital cycles tested?

Back 10

Delta 18 0 of foram. Nik Shackleton and others tested by measuring variation in O in foram tests from many oceanic locations.

Front 11

12. Where did the initial meltwater from the Wisconsin Glaciers initially drain?

Back 11

Lake Agassiz to North Atlantic

Front 12

cause of younger dryas

Back 12

changes of meltwater from gulf to north atlantic changed ocean currents

Front 13

increase diff btwn summer and winter temps

Back 13

obliquity

Front 14

15. What has been the dominant period of glacial cyclicity over the past ¾ of a million years?

Back 14

100,000 years

Front 15

which of the following would encourage growth of glaciers

Back 15

precession, less degree of tilt

Front 16

17. Which of the following controls the date (location in our orbit) at which seasons change?

Back 16

precession

Front 17

18. What is the primary cause of climate change over tectonic time scales?

Back 17

plate tectonics, atmospheric composition

Front 18

19. What climate shift contributed to the loss of Viking colonies in North America and Greenland?

Back 18

The Little Ice Age

Front 19

20. How does ice volume impact CO2 solubility in the worlds ocean?

Back 19

As temperature increases CO2 becomes more soluble. More ice the less soluble CO2 is.

Front 20

21. Match the orbital parameter to its corresponding periodicity:
Eccentricity -
Precession –
Obliquity (axial tilt) –

Back 20

98,000 year cycle
23,000
41000

Front 21

number of icehouse modes

Back 21

5 major and one minor

Front 22

what triggered the first known ice house

Back 22

weak sun, addition of CO2 by life, oxidation of methane

Front 23

24. Which location would be the best for measuring late Holocene sea surface temperature using oxygen isotope data from mollusk shells?

Back 23

Peru

Front 24

25. What type of proxy was used to measure past seasonal rainfall in what is now Turkey?

Back 24

Freshwater mollusk, lake

Front 25

26. How did climate change in Scotland during the Roman Warm Period?

Back 25

1 degree colder winters than the late 20th century winters and colder summers than now

Front 26

27. About how many hothouse periods have there been in the Phanerozoic (since the Cambrian)?

Back 26

More than a dozen (Kidder and Worsley) ~15

Front 27

28. What are marine oxygen isotope stages?

Back 27

Alternating warm and cool periods in Earth’s Paleoclimate

Front 28

29. What factors may help solve the “faint young sun paradox”?

Back 28

Earth may have had a similar atmosphere to Venus(which stores majority of carbon in atmosphere). Increased tectonic activity leads to uplift and new land, leading to increased weather. Weathering traps CO2 in resultant sedimentary rocks.

Front 29

30. What is El Niño?

Back 29

Oceanic circulation in the Pacific Ocean at irregular intervals ranging for 2-7 years warming period. Changes trade winds, cold water has long journey, then heats up the water, take time for winds to strengthen again and return to normal

Front 30

31. How has El Niño frequency changed over the Holocene?

Back 30

Began in the mid-holocene and has increase frequency since.

Front 31

32. What is the meaning of “precision” in a scientific measurement?

Back 31

The degree to which repeated measurements under unchanged conditions show the same results.

Front 32

33. How is precision typically assessed in scientific methods such as radiometric dating or stable isotope analyses?

Back 32

The standard deviation of bell curve proxy data.

Front 33

34. When testing Milankovitch’s ideas about orbital cycle and glacier expansion and retreat, scientists used only deep ocean, bottom dwelling foraminifera for oxygen isotope analysis. Why?

Back 33

Methane hydrate is located in the deep ocean.

Front 34

35. How might melting (ablation) of methane hydrate (also called methane clathrate) have led to climate change?

Back 34

Melting of CH4 leads to increase in CH4 gas which leads to increased warming

Front 35

36. How have scientists measured past major methane hydrate ablation events?

Back 35

Ice cores

Front 36

37. What does empirical mean?

Back 36

Based on concerned with, or verifiable by observation or experience rather than theory of pure logic.

Front 37

38. Which of the following is NOT a major cause of climate change in the past?

Back 37

Atmospheric composition, noise in the system, albedo, orbital variation, tectonics, polar heat transport, and the sun are major causes of climate change.