Climate Change Causes & Effects 2 — Questions and Answers
Question 1: Which agricultural practice is a significant source of methane emissions?
- Crop rotation
- Rice paddy cultivation (Correct answer)
- Drip irrigation
- Cover cropping
Correct answer: Rice paddy cultivation
Flooded rice paddies create anaerobic conditions where microbes produce methane as they decompose organic matter.
Question 2: What is the primary reason Arctic sea ice loss accelerates warming?
- Ice releases stored CO2 when it melts
- Dark ocean water absorbs more heat than reflective ice (Correct answer)
- Melting ice produces methane gas
- Sea ice blocks ocean currents that cool the atmosphere
Correct answer: Dark ocean water absorbs more heat than reflective ice
The ice-albedo feedback loop means that as white, reflective ice disappears, the darker ocean absorbs far more solar energy.
Question 3: How does climate change affect the timing of seasons for wildlife?
- It has no measurable effect on seasonal timing
- It causes phenological mismatches disrupting food availability (Correct answer)
- It uniformly shifts all seasons by the same amount
- It only affects marine species' seasonal behavior
Correct answer: It causes phenological mismatches disrupting food availability
Phenological mismatch occurs when species that depend on each other — like insects and migrating birds — shift their timing at different rates.
Question 4: Which sector is the largest source of greenhouse gas emissions in the United States?
- Industry
- Agriculture
- Transportation (Correct answer)
- Electricity generation
Correct answer: Transportation
Transportation surpassed electricity generation in 2016 to become the top source of US GHG emissions, primarily from cars and trucks burning fossil fuels.
Question 5: What is 'ocean acidification' and what causes it?
- Warming ocean temperatures caused by solar radiation
- Decreased ocean pH caused by absorption of CO2 (Correct answer)
- Increased salinity caused by glacier melt
- Oxygen depletion caused by algae blooms
Correct answer: Decreased ocean pH caused by absorption of CO2
Oceans absorb about 25% of atmospheric CO2, which reacts with seawater to form carbonic acid, lowering the ocean's pH.
Question 6: What role do permafrost thaws play in climate change?
- They reflect more sunlight back into space
- They release stored carbon as CO2 and methane, amplifying warming (Correct answer)
- They cool surrounding regions by releasing cold water
- They absorb additional CO2 from the atmosphere
Correct answer: They release stored carbon as CO2 and methane, amplifying warming
Permafrost contains vast amounts of ancient organic carbon; as it thaws, microbial decomposition releases CO2 and methane, creating a powerful feedback loop.
Question 7: Which of the following best describes the 'urban heat island' effect?
- Cities create their own regional rain patterns due to pollution
- Urban areas are significantly warmer than surrounding rural areas (Correct answer)
- Ocean cities experience less warming than inland cities
- Cities amplify global warming by emitting CO2 faster than forests absorb it
Correct answer: Urban areas are significantly warmer than surrounding rural areas
Dark pavement, buildings, and reduced vegetation cause cities to absorb and retain more heat than rural surroundings, raising local temperatures.
Climate Change Causes & Effects 2
Which agricultural practice is a significant source of methane emissions?