sea_level_lecture

Question 1

What is the Tide Gauges measure?

Answer 1

(Relative) Sea Level = ocean surface – ocean floor

Question 2

How does a Satellite Altimetry work?

Answer 2

Altimeter satellites send signal toward the sea surface and measure the two–way travel time of the reflection

Question 3

What are the dominant contributors to sea level rise?

Answer 3

• ice melting
• vertical land motion
• ocean-atmosphere interaction
• terrestrial water storage
• density changes
• ocean circulation

Question 4

Greenland ice would raise sea level by ~ ___meters

Answer 4

7

Question 5

Antarctic ice would raise sea level by ~ __ meters

Answer 5

57

Question 6

What will happen to sea level in Newfoundland if the Greenland Ice Sheet melts?

A.Sea level will fall
B.Sea level will stay approximately constant
C.Sea level will rise by about the global average
D.Sea level will rise by more than the global average

Answer 6

?

Question 7

What are the conditions that are necessary to form a glacier?

Answer 7

–Cold local climate (polar latitudes or high elevation).

–Snow must be abundant and accumulate in winter; more snow must fall than melts in the subsequent summer.

Question 8

What is the Milankovitch hypothesis?

Answer 8

• climate variation over 100 to 300 ka predicted by cyclic changes in orbital geometry.
• The shape of Earth’s orbit varies (~100,000 year cyclicity). - Tilt of Earth’s axis varies from 22.5o to 24.5o (~41,000 years).
• Precession—Earth’s axis wobbles like a top (23,000 years).

Question 9

Are we living in an interglacial (will ice return)?

Answer 9

–Very likely! Recent interglacials have lasted ~10,000 years.
–But, it has been ~11,000 years since the last deglaciation. –A cool period (1300–1850) resulted in the Little Ice Age