The Greenhouse Effect (College Board AP® Environmental Science): Flashcards
0Still learning
Know0
Define greenhouse gases (GHGs).
Was this flashcard helpful?
Cards in this collection (20)
Define greenhouse gases (GHGs).
Greenhouse gases (GHGs) are gases that trap heat in the atmosphere, regulating Earth's climate through the natural greenhouse effect.
What are the principal greenhouse gases?
The principal greenhouse gases are carbon dioxide (CO₂), methane (CH₄), water vapor (H₂O), nitrous oxide (N₂O), and chlorofluorocarbons (CFCs).
Which human activities have caused atmospheric CO₂ levels to rise?
Atmospheric CO₂ has risen because of burning fossil fuels and deforestation.
Deforestation decreases carbon storage because trees remove CO₂ from the atmosphere during .
Deforestation decreases carbon storage because trees remove CO₂ from the atmosphere during photosynthesis.
True or False?
The hole in the ozone layer causes global warming.
False.
The ozone hole lets more UV rays reach Earth, which increases skin cancer rates, but it has no effect on incoming solar energy and does not cause global warming.
Name two human activities that release methane.
Human activities that release methane include agriculture (particularly rice growing and livestock farming), fossil fuel extraction, and waste landfills.
Which agricultural activities emit nitrous oxide (N₂O)?
Nitrous oxide is emitted when nitrogen fertilizers and animal waste are used on farmland and pastures.
What is the most abundant greenhouse gas?
The most abundant greenhouse gas is water vapor.
True or False?
Water vapor is a major driver of long-term global climate change.
False.
Water vapor has a short residence time of a few days or even hours, so it does not drive climate change; instead, increased water vapor is a consequence of global warming.
Why does increased water vapor create a positive feedback loop?
A warmer atmosphere holds more water vapor, which amplifies the warming caused by other greenhouse gases and leads to greater evaporation.
Define greenhouse effect.
The greenhouse effect is the natural process in which greenhouse gases trap thermal energy re-emitted from Earth's surface and send it back in all directions, warming the surface.
Earth's surface absorbs energy from the sun and re-emits it as radiation.
Earth's surface absorbs energy from the sun and re-emits it as infrared radiation.
What would Earth's average surface temperature be without the greenhouse effect?
Without the greenhouse effect, Earth's average surface temperature would be about -18 °C instead of about 15 °C, making the planet uninhabitable.
Define enhanced greenhouse effect.
The enhanced greenhouse effect is caused by human activities releasing excessive greenhouse gases, so less infrared radiation escapes the atmosphere and global temperatures rise.
By how much have global average temperatures risen since pre-industrial times?
Global average temperatures have risen by over 1 °C since pre-industrial times.
Define global warming potential (GWP).
Global warming potential (GWP) is the amount of warming that 1 metric ton of a greenhouse gas would create compared with 1 metric ton of CO₂ over a 100-year timescale.
True or False?
Carbon dioxide has the highest GWP of any greenhouse gas.
False.
CO₂ is the baseline gas with a GWP of 1; gases such as methane and nitrous oxide are far more potent per metric ton.
Global greenhouse gas emissions are converted to CO₂ (CO₂e) by multiplying each gas by its 100-year GWP value.
Global greenhouse gas emissions are converted to CO₂ equivalents (CO₂e) by multiplying each gas by its 100-year GWP value.
Approximately how many times more potent than CO₂ is methane at warming the climate?
Methane is approximately 27-30 times more potent than CO₂ at warming the climate.
Why do policymakers use GWP?
Policymakers use GWP to prioritize which gases to reduce emissions of and to understand how different activities affect the climate overall.
Sign up to unlock flashcards
or