Lec 3 - Energy, Greenhouses, Icehouses

Question 1

What are the units of Force?

Answer 1

Newtons

Question 2

What are the units of Stress?

Answer 2

Force per area (N /m^2)

Question 3

What are the units of Work?

Answer 3

Force*Distance = Joules

Question 4

What is the unit of energy?

Answer 4

Joules

Question 5

What is the unit of Power?

Answer 5

Watt

Question 6

What 3 radiation laws describe the intensity/wavelengths of radiation?

Answer 6

Planck’s Law
Stefan-Boltzmann Law
Wien’s Law

Question 7

What is Planck’s Law?

Answer 7

defines the amount and spectrum of energy emitted from a body

Question 8

What is the difference between shortwave and longwave radiation?

Answer 8

• shortwave: less than 4 micrometers
• long-wave: greater than 4 micrometers

Question 9

What is the range of visible light’s wavelengths?

Answer 9

0.5-0.7 micrometers

Question 10

How does the amount of energy Earth receives from the sun differ from what we emit into space?

Answer 10

About the same!

Question 11

How does the climate respond to changes in CO2 concentration in icehouse vs. greenhouse climates?

Answer 11

Icehouse: very sensitive to CO2 changes (since there is very low concentration already)
greenhouse: not very sensitive to CO2 changes

• impacts of snow and ice, impacts of water-holding capacity at different temperatures

Question 12

What are the causes of tectonic-scale sea level changes?

Answer 12

• ocean ridges/rates of seafloor spread
• continental collision
• water stored in ice sheets

Question 13

What factors contributed to sea level change in past 80-100mya?

Answer 13

• decrease in ocean ridge volume
• collision of India and Asia
• water stored in ice sheets
• thermal contraction of seawater

Question 14

What evidence is there of cooling in past 50my?

Answer 14

• ice
• vegetation
• oxygen isotope measurements
• Mg/Ca measurements

Question 15

What is the gateway hypothesis?

Answer 15

Suggests that global temp changes are because of opening/closing of ocean gateways

Question 16

How would the BLAG hypothesis explain the cooling period in last 50my?

Answer 16

seafloor spreading has slowed since then, rates of volcanism have increased in last 15my

Question 17

What is required for uplift-weathering?

Answer 17

• lots of high-elevation terrain
• high terrain causes greater fragmentation
• exposure of fresh rock/debris must cause higher rates of chemical weathering