EOSC 110 MIDTERM 2 QUESTIONS AND ANSWERS
Describe the geologic processes that lead to the formation of coal, oil, and natural gas
deposits - Answer -Coal:
- Swamps or humid environments
- Vegetation
Oil and natural gas
- Oceans
- Micro-marine life
Explain the difference between climate forcing and climate feedbacks - Answer -
Climate forcing: Conditions change so that the environment is nudged towards a
particular change
Climate feedback: The response to climate forcing, the actual changes
Positive: Exaggerates the changes
Negative: Suppresses the changes
Describe the importance of albedo on Earth's climate, and how deforestation and the
melting of ice or snow affect albedo - Answer -Albedo
- Measure of reflectivity on Earth's surface, expressed as a percentage
- Important in reflecting back sunlight to cool the Earth
- High albedo: High reflectivity
Deforestation: Positive --> Vegetation reduces amount of CO2 in the atmosphere,
making deforestation a positive feedback
Melting of ice or snow: Positive --> Ice and snow melts into water, which has a lower
albedo than surface, thus absorbing more sunlight than it can reflect warming the Earth
Permafrost: Positive --> Soil contains trapped organic matter, which releases CO2 when
thawed
Describe and quantify Earth's carbon cycle - Answer -Carbon cycle is the exchange
between carbon reservoirs, typically at rather slow speeds.
Now, it is not being exchanged fast enough due to natural and anthropogenic positive
feedbacks, resulting in an increase of CO2 levels and warming of the Earth.
Summarize the properties of greenhouse gases and their role in controlling Earth's
climate - Answer -- Greenhouse gases have more than 2 atoms and can vibrate
through stretching AND bending
- Bending is slower and matches with the frequencies of IR rays
, This warms the Earth:
- Molecules emit IR rays
- More rigious vibrations warm the surrounding air
Increase in greenhouse gases --> increase in climate
Summarize the evidence for rapid recent climate change and the connection to human
activities - Answer -- Increase of surface temperatures
- Decline of arctic ice
- Increase in global sea level
- Increases of extreme weather events
Human activities: Release of greenhouse gases through fuel use, preventing the
escape of heat. Fuel mining releases CO2, which warms the Earth's environment.
Milkanovitch Cycles - Answer -- Eccentricity: Earth is less centered, more distance
variance between Earth and Sun
- Obliquity: Tilt of Earth towards or away from Sun
- Precession: Direction of rotational axis
Explain the hydrologic cycle - Answer -1. Water evaporates from lakes and streams
through solar heat
2. Water condenses in the atmosphere, forming water droplets
3. Water comes down as rain or snow due to gravity
4. Water on the surface infiltrates the ground
5. Groundwater slowly moves through rocks
6. Water returns to lakes and streams
Describe the characteristics of streams in terms of morphology, slope and base level -
Answer -Excess energy
- Erosion > deposition
- V shaped valleys
- Steep gradient
- Youthful
Balanced
- Erosion = deposition
- Meandering (oxbow, natural levee, cut banks, point bars)
- Moderate gradient
- Mature
Deficient
- Erosion < deposition
Describe the geologic processes that lead to the formation of coal, oil, and natural gas
deposits - Answer -Coal:
- Swamps or humid environments
- Vegetation
Oil and natural gas
- Oceans
- Micro-marine life
Explain the difference between climate forcing and climate feedbacks - Answer -
Climate forcing: Conditions change so that the environment is nudged towards a
particular change
Climate feedback: The response to climate forcing, the actual changes
Positive: Exaggerates the changes
Negative: Suppresses the changes
Describe the importance of albedo on Earth's climate, and how deforestation and the
melting of ice or snow affect albedo - Answer -Albedo
- Measure of reflectivity on Earth's surface, expressed as a percentage
- Important in reflecting back sunlight to cool the Earth
- High albedo: High reflectivity
Deforestation: Positive --> Vegetation reduces amount of CO2 in the atmosphere,
making deforestation a positive feedback
Melting of ice or snow: Positive --> Ice and snow melts into water, which has a lower
albedo than surface, thus absorbing more sunlight than it can reflect warming the Earth
Permafrost: Positive --> Soil contains trapped organic matter, which releases CO2 when
thawed
Describe and quantify Earth's carbon cycle - Answer -Carbon cycle is the exchange
between carbon reservoirs, typically at rather slow speeds.
Now, it is not being exchanged fast enough due to natural and anthropogenic positive
feedbacks, resulting in an increase of CO2 levels and warming of the Earth.
Summarize the properties of greenhouse gases and their role in controlling Earth's
climate - Answer -- Greenhouse gases have more than 2 atoms and can vibrate
through stretching AND bending
- Bending is slower and matches with the frequencies of IR rays
, This warms the Earth:
- Molecules emit IR rays
- More rigious vibrations warm the surrounding air
Increase in greenhouse gases --> increase in climate
Summarize the evidence for rapid recent climate change and the connection to human
activities - Answer -- Increase of surface temperatures
- Decline of arctic ice
- Increase in global sea level
- Increases of extreme weather events
Human activities: Release of greenhouse gases through fuel use, preventing the
escape of heat. Fuel mining releases CO2, which warms the Earth's environment.
Milkanovitch Cycles - Answer -- Eccentricity: Earth is less centered, more distance
variance between Earth and Sun
- Obliquity: Tilt of Earth towards or away from Sun
- Precession: Direction of rotational axis
Explain the hydrologic cycle - Answer -1. Water evaporates from lakes and streams
through solar heat
2. Water condenses in the atmosphere, forming water droplets
3. Water comes down as rain or snow due to gravity
4. Water on the surface infiltrates the ground
5. Groundwater slowly moves through rocks
6. Water returns to lakes and streams
Describe the characteristics of streams in terms of morphology, slope and base level -
Answer -Excess energy
- Erosion > deposition
- V shaped valleys
- Steep gradient
- Youthful
Balanced
- Erosion = deposition
- Meandering (oxbow, natural levee, cut banks, point bars)
- Moderate gradient
- Mature
Deficient
- Erosion < deposition