MODULE 3.2

Question 1

study of the Earth’s climate before instrumental records were available.

Answer 1

Paleoclimate

Question 2

The past ______________ years is far more stable than the previous ______________ years.

Answer 2

10,000; 400,000

Question 3

warmest temperature of Planet Earth

Answer 3

Paleocene-Eocene Thermal Maximum (PETM)

Question 4

coldest temperature of the Planet Earth

Answer 4

Last Glacial Maximum (LGM)

Question 5

sits between the warmest and coldest temperature of the Earth

Answer 5

Younger Dryas

Question 6

The 19th century is then characterized by_____________

Answer 6

rapid warming

Question 7

Before the 19th century, the temperature was caused by _______________, proven by ________________.

Answer 7

natural variability; paleoclimate archives

Question 8

During the 19th century, rapid warming is caused by ________________ and _________________.

Answer 8

human activities; instrumental records

Question 9

These are what paleoclimate scientists use to study past climates, otherwise known as geologic archives. Examples include ice cores, tree rings, sediments, corals, cave deposits, and more.

Answer 9

Paleoclimate archives

Question 10

physical, chemical, and biological materials preserved within paleoclimate archives that can be analyzed and correlated with climate or environmental parameters in the modern world

Answer 10

Paleoclimate proxies

Question 11

These are examples of physical proxies

Answer 11

sediment composition, sediment texture, color, density, and magnetic properties

Question 12

These are examples of chemical proxies

Answer 12

stable isotopes, elemental analyses, biomarkers, and Biogenic Silica

Question 13

These are examples of biological proxies

Answer 13

charcoal and micro/macrofossils like Pollen, Foraminifera, Ostradoces, Diatoms, Dinocysts, and other Algae, Corals, and Mollusks

Question 14

Direct measurements from instrumental and historical records have time limitations, specifically spanning ______________ and _______________ years respectively.

Answer 14

100, 1000

Question 15

Historical records are often ____________________

Answer 15

qualitative and incomplete

Question 16

____________________ allows scientists to reconstruct a more reliable, consistent story, and longer climate history.

Answer 16

Comparing multiple proxy sources against each other

Question 17

This paleoclimate archive collects data from oxygen and carbon isotope from bottom dwelling deep sea foraminfera and reveals what climate looked like 70 million years ago.

Answer 17

Deep sea record

Question 18

Most of the trends from the data are controlled by __________________ and reflect sudden input of _________________ from deep inside the Earth.

Answer 18

tectonic activity; hydrothermal fluids

Question 19

Global temperatures reached a maximum at about ________________, after which cooling began.

Answer 19

55 million years ago

Question 20

This cooling resulted from three main events:

Answer 20

1. collision of India with Asia
2. reduction in seafloor spreading rates
3. rise of Andean Mountain

Question 21

The first half of the Cenozoic likely saw _______________ polar regions.

Answer 21

ice-free

Question 22

major drivers of climate on the scale of millions of years of change

Answer 22

Plate tectonics

Question 23

Discuss the implications of fast seafloor spreading

Answer 23

Rapid CO2 input —> Warm greenhouse climate —> Increased chemical weathering —> Increased CO2 removal —> Reduced warming

Question 24

Discuss the implications of slow seafloor spreading

Answer 24

Slow CO2 input —> Cold greenhouse climate —> Decreased chemical weathering —> Decreased CO2 removal —> Reduced cooling

Question 25

The position of continents affects _________________ and _________________, which are the two conveyor belts responsible for _________________ from the equatorial regions and moving it to the polar regions.

Answer 25

ocean, atmospheric circulation; taking excess heat

Question 26

This paleoclimate archive is layered annually, contain trapped air bubbles, which preserve atmospheric gases like CO2 and methane; tell us about the climate 400,000 years ago (though the last 10,000 years have been more stable)

Answer 26

Ice cores

Question 27

Sometimes, these can be found in ice cores, which help to date the ice; from volcanic activity

Answer 27

Dark ash layers

Question 28

This concept allows us to use modern relationships to infer past climate conditions.

Answer 28

Uniformitarianism

Question 29

This caused changes in temperature when the snow fell.

Answer 29

Variations in the ratio of lighter and heavier isotopes of oxygen and hydrogen

Question 30

Which is heavier: 16-O or 18-O? What are the implications of this?

Answer 30

18-O; Due to 16-O being lighter, it evaporates faster.

Question 31

During colder times, there are more _______ than _______ because _________________.

Answer 31

18-O and 16-O; The evaporated 16-O gets stored in ice sheets on continents.

Question 32

pioneer in the use of mass spectometry to determine changes in climate as recorded in the oxygen isotope composition of calcareous microfossils (Foraminifera)

Answer 32

N.J. Shackleton

Question 33

The last magnetic field reversal was _________________

Answer 33

780,000 years ago

Question 34

The Ice Ages have periods of about:

Answer 34

100,000; 40,000; 20,000

Question 35

Shackleton along with ________ and _________ concluded that the periods of the Ice Ages correspond with Earth's ________________

Answer 35

orbital pattern

Question 36

The dominant, 100,000-year climatic comonent has an average period close to, and is in phase with, ______________.

Answer 36

orbital eccentricity

Question 37

Eccentricity changes how close Earth is to the sun, affecting ____________________.

Answer 37

the amount of solar radiation the planet receives

Question 38

During the Younger Dryas, temperatures in _________________ reached near-glacial conditions; _________________ experienced a 10 degree Celsius change

Answer 38

Northern Hemisphere; Greenland

Question 39

The ___________________ carries warm water to the region around Iceland where cooling by cold Canadian air masses densifies the water, allowing it to sink to the bottom, forming a southward-moving water mass.

Answer 39

Great Ocean Conveyor

Question 40

The flow of water (20 million cubic meters per second) is equal to the _____________________

Answer 40

amount of annual global rainfall

Question 41

The heat released to the atmosphere keeps Northern Europe _________________ than it would be were the conveyor to shut down.

Answer 41

5 - 10 degrees Celsius warmer

Question 42

Instrumental record since 1850 includes:

Answer 42

weather stations, weather balloons, aircrafts, and a variety of satellites

Question 43

Period of regional cooling from the 1300s to the 1850s, particularly pronounced in the North Atlantic Region.

Answer 43

Little Ice Age

Question 44

Under LIA, glaciers across ______________, ______________, and ______________ were more prominent. Temperatures ______________ in Spring and ______________ in Autumn.

Answer 44

Alaska, Europe, New Zealand; rose later, dropped sooner

Question 45

Agricultural records show that growing seasons during LIA were __________________ than in the 20th century due to the extreme cooling period

Answer 45

15 to 20% shorter

Question 46

Even an average temperature drop of just ________ can have a marked effect on agriculture.

Answer 46

0.5 degree Celsius

Question 47

LIA was a time of more extremes in _____ prices. Using the price of this crop as an indicator shows that more frequent extreme weather leads to more frequent economic difficulty.

Answer 47

Rye

Question 48

accounts for as much as 40% of the decadal-scale variance during the LIA

Answer 48

Volcanism

Question 49

measure of stratopheric transparency to incoming solar radiation

Answer 49

Aerosol optical depth

Question 50

Discuss how sulfur-rich volcanic eruptions can induce surface cooling.

Answer 50

The most significant climate impacts from volcanic injections into the stratosphere come from the conversion of sulfur dioxide to sulfuric acid, which condenses rapidly in the stratosphere to form fine sulfate aerosols. The aerosols increase the reflection of radiation from the Sun back into space, cooling the Earth's lower atmosphere or troposphere.

Question 51

period of extremely low solar activity from approximately AD 1650 TO 1715; a reduction in total solar irradiance likely contributed to the LIA at a level comparable to changing land use.

Answer 51

Maunder minimum

Question 52

A lighter 18-O indicates a ___________ East Asian monsoon rainfall.

Answer 52

stronger

Question 53

a period of strong rainfall about AD 1000 when rice became the dominant staple of the Chinese diet and there was a great expansion of the Chinese population.

Answer 53

Northern Song Strong Monsoon Period

Question 54

In contrast, there were times of weak monsoon and political instability.

Answer 54

1. Late Tang Weak Monsoon Period 2. Late Yuan Weak Monsoon Period 3. Late Ming Weak Monsoon Period

Question 55

these show a record of the weakening and strengthening of the East Asian monsoon over the past _______________.

Answer 55

Stalagmites in a cave at Wanxiang, China; 1,800 years

Question 56

used changes in the ratio of 18-O and 16-O to show strengthening and weakening of the East Asian monsoon

Answer 56

Zhang et al (2008)

Question 57

is actually isotopically “heavier” that water that falls a couple days later, farther inland.

Answer 57

The rain that falls on the Chinese coast

Question 58

In years when the monsoon is stronger, that is, when more rain falls as the storms move across China, the water __________ is lighter than in years when the monsoon is weak.

Answer 58

falling inland

Question 59

During wet periods around __________________, the water laden with calcium and carbonate dripped from the ceiling of the cave and evaporated, leaving the calcium carbonate (limestone) as a _______________.

Answer 59

65,000 and 39,000 years ago; stalagmite

Question 60

fueled by a drought, when locusts swarmed the land, and led to the end of the Tang Dynasty

Answer 60

Huang Chao Uprising of the 870s and 880s

Question 61

At the end of the ________________, there were a series of droughts and a peasant uprising. In 1368 _________________, the leader of the uprising, took Beijing. His parents and older brother all died during the droughts.

Answer 61

Yuan Dynasty; Zhu Yuanzhang

Question 62

known as one of the most severe droughts in Chinese history at the end of the Ming Dynasty (1637-1643); affected more than 20 provinces in N and S China. The prolonged drought helped Li Zicheng organize a popular uprising and overthrow Chongzhen in 1644.

Answer 62

Chongzhen Drought

Question 63

Variations in climate can be dangerous to societies and civilizations because it challenges:

Answer 63

political stability, food security, water security, and human progress