Environmental Science Climate Change and Atmosphere

Question 1

Which layer of the atmosphere contains the ozone layer that protects Earth from UV radiation?

Accepted Answer

Stratosphere

Answer

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?

Accepted Answer

About 28–36 times greater

Answer

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?

Accepted Answer

Paris Agreement

Answer

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?

Accepted Answer

Thermal expansion of seawater and melting land ice

Answer

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?

Accepted Answer

Ice-albedo feedback

Answer

As ice melts, it exposes darker ocean or land surfaces with lower albedo, absorbing more solar energy and warming further.

Environmental Science Practice Test