Its Happening: Evidence for Recent Climate Change

Question 1

What is a temperature anomaly? How are they calculated?

Answer 1

1. A change in temperature from a reference value or long-term average, help to discern threats and patterns
2. Subtract average from normal/reference

Question 2

Urban heat-island effect

Answer 2

Population growth around weather stations can lead to a LOCALLY increase of temp of up to 3 degrees celsius, bias for global temp accounted for when calculating area-weighted temp changes regionally

Question 3

How much has global average temperature increased over the past 150 years?

Answer 3

1 degree celsius

Question 4

Has the temperature rise been a smooth increase, or has it been step-like?

Answer 4

Step-like, with certain periods of more rapid warming followed by periods of stable temperatures.

Question 5

What may have caused the stable/cooling period from the 1940’s to 1970’s?

Answer 5

Increase in aerosols

Question 6

ow do satellite temperature measurements compare with surface temperature measurements?

Answer 6

Generally agree, and provide confirmation of global warming

Question 7

Where on Earth are temperatures rising most rapidly?

Answer 7

High Northern Latitude’s

Question 8

How does warming over land compare with warming over the ocean?

Answer 8

Warming over land occurs more quickly since it has a lower heat index compared to the ocean, more energy from global warming going into the ocean

Question 9

Name the various components of the cryosphere:

Answer 9

1. Sea Ice
2. Permafrost
3. Icebergs and ice shelves
4. Glaciers and ice sheets
5. Snow on ground
6. lake and river ice

Question 10

How have mountain glaciers and the two ice sheets changed during the last several decades?

Answer 10

1. Mountain glaciers retreating and thinning at an alarming rate worldwide, due to increasing summer temperatures
2. Both arctic and greenland ice sheets are losing mass, however greenlands ice sheet is losing slightly more

Question 11

By how much has sea level risen during the past 100 years and what is its current trajectory?

Answer 11

17cm at a recently accelerating rate

Question 12

What is the largest source of meltwater causing sea level to rise?

Answer 12

Glaciers

Question 13

Does melting sea ice affect sea level?

Answer 13

No

Question 14

What is sea ice and how is it involved in a reinforcing (positive) feedback on warming?

Answer 14

As more ice melts and exposes more dark water, the water absorbs more sunlight. The sun-warmed water then melts more ice

Question 15

Name multiple types of evidence other than temperature records that show global warming is happening.

Answer 15

1. Sea Level rise
2. Increase in surface temperature and ocean temperature
3. Decrease in sea ice, snow cover, glaciers and ice sheets

Question 16

What factors determine confidence in a scientific finding?

Answer 16

Larger sample size, when the evidence and agreement have a positive correlation