Climate Reconstruction

Question 1

Why did past climates change?

Answer 1

Natural processes

Question 2

What is climate sensitivity?

Answer 2

Change in climate for a given forcing

Question 3

When did central England temperature records begin?

Answer 3

• Monthly since 1659

- Daily since 1772

Question 4

Advantages of climate proxies …

Answer 4

Very long record

Question 5

Disadvantages of climate proxies …

Answer 5

• no proxy record responding solely to one variable
• limited resolution (space and time)
• must be preserved
• overprinting of original signal

Question 6

What controls the width of tree rings?

Answer 6

Temperature and moisture availability

Question 7

How are tree rings biased?

Answer 7

They are biased towards the growing season

Question 8

How old is the oldest tree ring record?

Answer 8

9000 years

Question 9

What is an isotope?

Answer 9

Chemically identical form of an element with a different atomic mass

Question 10

What percentage of seawater has O18?

Answer 10

0.19%

Question 11

What percentage of fresh water has O18?

Answer 11

0.15%

Question 12

Which oxygen isotope is preferentially evaporated?

Answer 12

O16

Question 13

Which oxygen isotope is preferentially ‘rained out’?

Answer 13

O18

Question 14

What two uses are there for O isotopes?

Answer 14

• Glaciation

- Temperature indicator

Question 15

What happens to O18 during glaciation?

Answer 15

Enrichment of O18 in sea water (colder temperature, O18 remains in oceans as it’s heavier)

Question 16

How do ice cores date?

Answer 16

By counting layers of by analysing dust layers

Question 17

Where was the longest ever ice core drilled?

Answer 17

Antarctica

Question 18

How many glacials cycles did the longest ice core display?

Answer 18

8 glacial-interglacial cycles

Question 19

What is the difference between Antarctic and Greenland ice cores?

Answer 19

Greenland ones have a shorter record (only covers the last glacial cycle) BUT they have a higher resolution … same length of core but shows a shorter amount of time

Question 20

Typically how far back do written records go?

Answer 20

1000 years

Question 21

Example of a written record: when was it? who noted it? what did it show?

Answer 21

1801: William Herschel noted a correlation between sunspot numbers and wheat prices

Question 22

What is the little ice age?

Answer 22

Movement of Europe into a cold period during the 16th century

Question 23

What were temperatures like during the Little Ice Age?

Answer 23

From 1550 for about 150 years, temperatures were lower than at any time since the last glacial ended over 10,000 years ago

Question 24

Who painted ‘Hunters in the Snow’? When? What was it inspired by?

Answer 24

Pieter Brueghel, 1565 … said to be inspired by the longest and most sever Dutch winter at the time

Question 25

What happened to sea ice extent during the Little Ice Age?

Answer 25

Sea ice extended as far south as the Faeroe Islands ... 1695: sea ice surrounded Iceland, blocking ports and disrupting supply

Question 26

What impact did advancing glaciers in Scandinavia during the Little Ice Age have?

Answer 26

- highland farms destroyed - outburst floods from stored meltwater - famine due to damaged harvests

Question 27

Impact of the little ice age ...

Answer 27

- N Sea flooding in 1570 - Failure of cod fisheries from 1615 for a century - 1703 great storm

Question 28

What is the Medieval climate anomaly?

Answer 28

Warming from 600 AD to 1250 AD in Europe

Question 29

The period between 1983-2012 was ...

Answer 29

- very likely the warmest 30 year period of the last 800 years - likely to have been warmest in last 1400 years

Question 30

What is the difference between the Medieval Climate Anomaly and 20th century warming?

Answer 30

Regional warm periods in the past were not as synchronous across regions as modern warming