Which compares the effectiveness of methane and nitrous oxide as a greenhouse gas with that of carbon dioxide?

Question

Neither methane nor nitrous oxide is a more effective greenhouse gas than carbon dioxide.
Neither methane nor nitrous oxide is a more effective greenhouse gas than carbon dioxide.

Only methane is a more effective greenhouse gas than carbon dioxide.
Only methane is a more effective greenhouse gas than carbon dioxide.

Both methane and nitrous oxide are more effective greenhouse gases than carbon dioxide.
Both methane and nitrous oxide are more effective greenhouse gases than carbon dioxide.

Only nitrous oxide is a more effective greenhouse gas than carbon dioxide.

Answer 1

To compare the effectiveness of methane (CH₄) and nitrous oxide (N₂O) as greenhouse gases with that of carbon dioxide (CO₂), it is important to look at their global warming potentials (GWPs).

1. Carbon Dioxide (CO₂): The reference gas for GWP, with a value of 1.
2. Methane (CH₄): Over a 20-year period, methane has a GWP of approximately 84-87, and over a 100-year period, it's about 28-36 times more effective than CO₂ at trapping heat in the atmosphere.
3. Nitrous Oxide (N₂O): Over both 20 and 100-year periods, nitrous oxide has a GWP of about 298, making it significantly more effective than CO₂.

Given this information, it can be concluded:

• Both methane and nitrous oxide are more effective greenhouse gases than carbon dioxide.

Thus, the correct comparison is:

Both methane and nitrous oxide are more effective greenhouse gases than carbon dioxide.