Quaternary Quiz: Lectures 14-26

Question 1

What were CO2 and CH4 levels like in the glacial-interglacial cycles compared to the present?

Answer 1

Glacials - CO2 250ppm / CH4 450ppb

Interglacials - CO2 280ppm / CH4 650ppb

Present day - CO2 400ppm and CH4 1800ppb!

Question 2

What is the perihelion and aphelion?

Answer 2

Perihelion - Earth’s closest point to the Sun

Aphelion - Earth at its furthest point to the Sun

Question 3

Age order for hominids out of Homo heidelbergensis, Astralopithecus afarensis, Homo neanderthalis and habilis?

Answer 3

Astra…
Habilis
Heidelbergensis
Neanderthal

Question 4

What and when was the Devensian and the LGM?

Answer 4

Devensian = the last glacial, 110Ka up to 11.7Ka

Last Glacial Maximum, 21Ka (within the last glacial!)

Question 5

How thick was the last British ice-sheet and where did it extend to? What was Doggerland?

Answer 5

1.5 km thick
To south Wales and north Norfolk, but not linear

Doggerland was a large mass of land (submerged 8Ka) that connected British isles to Europe

Question 6

Dates of the Younger Dryas and its cause? What ice-sheet re-expanded during it and what is another explanation for it?

Answer 6

12.5-11.5Ka (a cold snap)

Driven by freshwater influx after the Lake Agassiz outburst

Glaciers in Western Scotland

Shocked quartz implies an impact event in N America.

Question 7

What are Dansgaard-Oeschger events and Heinrich events; how many have occurred in the past 120,000 (DO) and 60,000 (H) years?

Answer 7

DO = abrupt warming events, 25

H = massive iceberg rafting events in North Atlantic, 6

Question 8

Describe the seasonal atmospheric cycle that drives the Asian monsoon.

What does Loess show?

How does the Asian monsoon vary over glacial-interglacial timescales?

Answer 8

Summer warms land faster than the ocean, where low pressure air rises ocer land, drawing moist air from the ocean, so the winter cycle is reversed.

The grain size of Loess deposits reflects the strength of the winter monsoon winds.

Strong during glacials, weaker in interglacials

Question 9

What and when is the Eemian?

Answer 9

MIS5e, called the Ipswichian in the UK; the last interglacial dating to 130-116Ka

Question 10

During the last interglacial, was the UK inhabited? What were the winter ice limits in the northern hemisphere compared to today? How was the sea-level and temperature (average) different?

Answer 10

Yes, along with African wildlife

Winter ice 800km further north

Sea-level 8m higher than today, 2 degrees warmer

Question 11

Which Milankovitch cycles are of particular importance during the Holocene?

Answer 11

Precession causing summer insolation changes

Question 12

Describe the global change in climate after 6000 cal yr BP

Answer 12

Decline in northern high temperatures, and a decline in the Asian monsoon due to reduced continental heating

Question 13

What is the duration of a Bond cycle?

Answer 13

Small, abrupt climate changes in the Holocene; 1500 yr cycles

Question 14

What and when was the Medieval warm period and LIA? What are the main forcing factors driving climate in the Late-Holocene?

Answer 14

MWP = AD950-1250; warm and moist in the N Atlantic

Little Ice Age = 1300-1870; cold and icy in N Atlantic

Volcanic, orbital and anthropogenic (GHGs, deforestation)

Question 15

What was the earliest evidence for hominids in the UK?

Answer 15

Happisburg footprints and stone tools, dating to 990-780Ka

Question 16

What was the earliest evidence for H. heidelbergensis in the UK?

Answer 16

Swanscombe ‘woman’, 400Ka

Question 17

Where were the main centres of agricultural development in the Neolithic? What were the key Neolithic crops?

Answer 17

Turkey-Iraq (Fertile Crescent)
North Africa
India
Northern South America
China

Maize, teonsite, millet and rice