Climate Change Environmental Science Fundamentals 3 â Questions and Answers
Question 1: How does deforestation in tropical regions contribute to climate change beyond simply removing carbon-absorbing trees?
- It increases ocean salinity levels
- Burning cleared vegetation releases stored carbon and reduces regional rainfall patterns (Correct answer)
- It causes the jet stream to shift northward
- It increases methane production from soils
Correct answer: Burning cleared vegetation releases stored carbon and reduces regional rainfall patterns
Tropical deforestation releases the carbon stored in trees through burning or decomposition and disrupts regional water cycles, reducing evapotranspiration that drives rainfall and can turn forests into savanna.
Question 2: Which metric best describes a country's total contribution to atmospheric warming over time, accounting for historical emissions?
- Current annual COâ emissions rate
- Cumulative greenhouse gas emissions (Correct answer)
- GDP-adjusted emissions intensity
- Per capita daily energy consumption
Correct answer: Cumulative greenhouse gas emissions
Cumulative emissions are the most relevant metric because COâ persists in the atmosphere for centuries, meaning historical emissions from industrialized nations have contributed disproportionately to current warming.
Question 3: What is 'blue carbon' in the context of climate mitigation?
- Carbon captured and stored by oceanic plankton in the deep sea
- Carbon stored in coastal and marine ecosystems like mangroves, seagrasses, and salt marshes (Correct answer)
- The carbon dissolved as carbonate ions in ocean water
- Liquid COâ injected into deep ocean sediments
Correct answer: Carbon stored in coastal and marine ecosystems like mangroves, seagrasses, and salt marshes
Blue carbon ecosystemsâmangroves, seagrasses, and tidal marshesâsequester carbon at rates up to 10 times higher per area than terrestrial forests, making their conservation critical for climate mitigation.
Question 4: Why is the Arctic warming approximately four times faster than the global average?
- Arctic air masses contain more water vapor
- The ice-albedo feedback loop amplifies warming as reflective ice is replaced by dark ocean (Correct answer)
- Ozone depletion over the poles allows more UV radiation in
- Methane from tundra creates localized warming only in the Arctic
Correct answer: The ice-albedo feedback loop amplifies warming as reflective ice is replaced by dark ocean
As white, reflective sea ice melts, it exposes dark ocean water that absorbs far more solar energy, creating a feedback loop where warming causes more melting, which causes more warmingâthis is Arctic amplification.
Question 5: What does 'net-zero emissions' mean in climate policy?
- A country stops all industrial greenhouse gas production
- The amount of greenhouse gases emitted is balanced by the amount removed from the atmosphere (Correct answer)
- A company uses 100% renewable energy for its operations
- Total global emissions are equal across all nations
Correct answer: The amount of greenhouse gases emitted is balanced by the amount removed from the atmosphere
Net-zero means that any remaining greenhouse gas emissions are offset by equivalent carbon removal through natural sinks or technological methods, resulting in no net addition to atmospheric concentrations.
Question 6: How do aerosols from volcanic eruptions affect short-term global temperature?
- They trap outgoing infrared radiation, causing temporary warming
- They reflect incoming solar radiation, causing temporary cooling (Correct answer)
- They react with methane to produce additional COâ
- They seed cloud formation that increases precipitation globally
Correct answer: They reflect incoming solar radiation, causing temporary cooling
Volcanic aerosols, primarily sulfur dioxide that converts to sulfate particles, reflect incoming sunlight back into space, causing measurable global cooling for one to three years after major eruptions.
Question 7: Which agricultural practice is considered a significant source of methane emissions contributing to climate change?
- Drip irrigation in arid regions
- Flooded rice paddies and livestock digestion (Correct answer)
- No-till farming on croplands
- Controlled burning of crop residues
Correct answer: Flooded rice paddies and livestock digestion
Flooded rice paddies create anaerobic conditions where methane-producing microbes thrive, and cattle and other ruminants release methane through enteric fermentation during digestion.
Climate Change Environmental Science Fundamentals 3
How does deforestation in tropical regions contribute to climate change beyond simply removing carbon-absorbing trees?