Environmental Science Climate Change and Atmosphere 1 — Questions and Answers
Question 1: Which layer of the atmosphere contains the ozone layer that protects Earth from UV radiation?
- Troposphere
- Stratosphere (Correct answer)
- Mesosphere
- Thermosphere
Correct answer: Stratosphere
The stratospheric ozone layer (15–35 km altitude) absorbs harmful UV-B and UV-C radiation from the sun.
Question 2: What is the global warming potential (GWP) of methane compared to CO₂ over a 100-year timeframe?
- About 5 times greater
- About 28–36 times greater (Correct answer)
- About equal
- About 300 times greater
Correct answer: About 28–36 times greater
Methane's 100-year GWP is approximately 28–36 times that of CO₂, making it a potent but shorter-lived greenhouse gas.
Question 3: Which international agreement, adopted in 2015, aims to limit global temperature rise to 1.5–2°C above pre-industrial levels?
- Kyoto Protocol
- Montreal Protocol
- Paris Agreement (Correct answer)
- Rio Declaration
Correct answer: Paris Agreement
The Paris Agreement commits nations to nationally determined contributions (NDCs) to reduce emissions and limit warming.
Question 4: Rising sea levels due to climate change are primarily caused by two processes. What are they?
- More rainfall and dam construction
- Thermal expansion of seawater and melting land ice (Correct answer)
- Ocean acidification and increased evaporation
- El Niño events and tidal changes
Correct answer: Thermal expansion of seawater and melting land ice
Warmer water expands (thermal expansion) and melting glaciers/ice sheets add water volume, both raising sea levels.
Question 5: Which feedback mechanism amplifies warming by reducing Earth's reflectivity as polar ice melts?
- Carbon cycle feedback
- Ice-albedo feedback (Correct answer)
- Water vapor feedback
- Planck feedback
Correct answer: Ice-albedo feedback
As ice melts, it exposes darker ocean or land surfaces with lower albedo, absorbing more solar energy and warming further.
Question 6: What is the Keeling Curve?
- A graph of global temperature anomalies since 1850
- A continuous record of atmospheric CO₂ concentration at Mauna Loa (Correct answer)
- A plot of Arctic sea ice extent over time
- A map of ocean acidity changes
Correct answer: A continuous record of atmospheric CO₂ concentration at Mauna Loa
The Keeling Curve is the continuous record of atmospheric CO₂ measured at Mauna Loa Observatory since 1958.
Environmental Science Climate Change and Atmosphere 1
Which layer of the atmosphere contains the ozone layer that protects Earth from UV radiation?