Week 7 - Past Climates

Question 1

Why are there differences between the Toronto downtown and airport temperature records?

Answer 1

Because of the urban heat island effect.

Question 2

Why have the differences between Toronto Tmax and Tmin been getting smaller during the past century?

Answer 2

Because the urban heat island effect is really only visible at Min temps (overnight).

Question 3

What other long term instrumental records exist in the world?

Answer 3

Uppsala, Stockholm, Central England

Question 4

What are the issues with the Global Historical Climate Network?

Answer 4

The stations are mostly concentrated in America and Europe; also, the stations haven’t been around that long.

Question 5

How accurate are instrumental records?

Answer 5

Not great. Problems include: thermometer calibration, standards of measurement, early rainfall and snow measurements probably underestimated.

Question 6

What are the issues with automatic weather stations?

Answer 6

Accuracy and compatibility with older records.

Question 7

What does the Kobe collection of data contribute to the historical temperature record?

Answer 7

Pressure, SST, winds.

Question 8

What is Kobe?

Answer 8

Kobe Marine Observatory, Japan Meteorological Agency

Question 9

Where does Kobe get its information?

Answer 9

Collected and archived weather data from ships, 1890-1960

Question 10

What does the Global Reanalysis Project seek to do?

Answer 10

It seeks to fill the holes from 20th century data, help smooth over inconsistencies across sources, and employ new technology (satellites).

Question 11

What contributions do satellite measurements make to the climate record?

Answer 11

Temperature, precipitation, sea ice and snow cover, and wave height and ocean altitude.

Question 12

What is the measure of altitude called?

Answer 12

Altimetry

Question 13

What does the instrumental record of temperature tell us about temperature during the period 1850-present?

Answer 13

That the temperature is steadily rising.

Question 14

What is the relationship between 16O and 18O in ice cores and ocean sediments during glacial times?

Answer 14

During glacial times, 16O will evaporate and become trapped in ice sheets. That means more 18O in the ocean, which means more 18O in the foraminifera, which means more 18O in ocean sediment and more 16O in ice cores.

Question 15

What is the relationship between 16O and 18O in ice cores and ocean sediments during interglacial times?

Answer 15

During interglacial times, 16O evaporates and goes back to the ocean, which means you’ll find a balance between ice sheets and oceans.

Question 16

What does the oxygen isotope record show us about climate?

Answer 16

There have been at least 20 major glacial-interglacial cycles on Earth in past 2 MY.

Question 17

How do boreholes show past temperatures of the atmosphere?

Answer 17

Once you’ve taken into account the energy from the Earth and other complicated math stuff, you can calculate the contribution from the sun, and therefore surface temps.

Question 18

What is a proxy climate record?

Answer 18

Proxy = substitute. Climate for periods prior to the development of measuring instruments, including historic and geologic time.

Question 19

What types of historical record can contribute to an understanding of climate change?

Answer 19

Diaries, ship logs, port accounts, merchant accounts, and newspapers.

Question 20

What is pollen analysis, and how does it contribute to an

understanding of climate change?

Answer 20

By understanding what plants were around (as seen in lake sediment), we are able to determine the weather and climate at that time because types of plant species relates to weather.

Question 21

What characteristics of tree rings can tell us something about paleoclimate?

Answer 21

They’re width, density, and isotopic composition.

Question 22

How do dendroclimatologists extend the climate record back beyond the age of living trees?

Answer 22

By lining up living trees with deadwood and dendroarchaeological samples.

Question 23

How much of the Earth is land and what should Earth probably be called?

Answer 23

Earth is 30% land and should probably be called Ocean.

Question 24

What’s the foraminifera for a Friday night?

Answer 24

Neogloboquadrina pachyderma

Question 25

How are deep sea cores obtained?

Answer 25

By drilling into the ocean floor with giant, CIA-funded boats.

Question 26

Why is Neogloboquadrina pachyderma important in the

oceanic record of climate change?

Answer 26

Left-handed coils mean cooler overall temps; right-handed vice versa.

Question 27

What is an isotope, and what oxygen isotopes are useful in understanding climate change?

Answer 27

An isotope is the same element with a different atomic mass. 16O and 18O.

Question 28

What contribution can lake sediments make to the climate record?

Answer 28

Charcoal can show forest fires, therefore hot conditions. Coarse sediment can show runoff, so wet conditions. Also, pollen.

Question 29

Why are there some differences between the historical
temperature records of the northern and southern
hemispheres?

Answer 29

Continentality.

Question 30

Which place as the longest temperature series?

Answer 30

Central England

Question 31

What can deep sea sediment tell us about?

Answer 31

The history of global temperature and ice ages.

Question 32

What kind of terrain does the Kobe collection focus on?

Answer 32

Oceans

Question 33

What are some examples of proxy climate records?

Answer 33

Tree rings, ice cores, pollen, sediments, boreholes, etc.

Question 34

Which area of the world has the best geographic coverage of historic weather data?

Answer 34

Europe

Question 35

What two things can borehole records tell us about?

Answer 35

Temperature fluctuations in the atmosphere and heat flow from the Earth.

Question 36

What are the strengths of the Central England temp series?

Answer 36

Longest records, plus they’re British, and therefore smarter

Question 37

What are the weaknesses of the Central England temp series?

Answer 37

Large area, calibration, inaccuracies, roving stations