Econ II - Session 9

Question 1

Greenhouse effect

Answer 1

Phenomenon within the atmosphere of the earth.
Certain gasses let short-wave light (visible light) pass but
absorb long-wave light (heat)

Question 2

Earth radiation equilibrium

Answer 2

Incoming energy = outgoing energy (different type of radiation, longer waves)

Question 3

What accelerates ice sheet melting once it started?

Answer 3

When the ice sheet melt, melting accelerates as lower ice faces warmer air (like up in the mountains, it’s cooler)

Question 4

By what is earth’s energy balance affected?

Answer 4

• Increased CO2 concentration
• Increased concentration of other GHG (methane, …)
• Change in surface albedo (reflection)
• Atmospheric pollution that reflects sunlight (aerosols)
• Change in solar activity

Question 5

1. Carbon cycle
2. three major “sinks” for CO2

Answer 5

Carbon cycle: how much of the emitted CO2 remains in the atmosphere (after photosynthesis, ocean absorption etc.)

1. Ocean: CO2 is chemically absorbed
2. Vegetation: Through photosynthesis
3. Atmosphere 🫠

Question 6

Negative feedback mechanism (climate)

Answer 6

warming –> atmosphere can hold up more water vapor –> more clouds –> cooling –> –> warming

Question 7

positive feedback mechanism (climate)

Answer 7

warming –> ice melting –> decrease albedo –> more insolation (= Sonneneinstrahlung) absorbed –> warming

Question 8

principle mechanisms of climate change

Answer 8

Greenhouse effect
Carbon cycle

Question 9

Indicators for climate change

Answer 9

• Radiative forcing (GHG concentration in atmosphere)
• Temperature
• Sea level
• Ocean heat content
• Ice and snow cover

Question 10

Why is the sea level rising?

Answer 10

• Melting mountain glaciers / greenland & arctic ice sheet –> more water
• Warmer water has more volume (thermal expansion)