The question requires ordering the following greenhouse gases based on the amount of extra warming they produce in Earth's atmosphere:
- A. $CO_2$ (Carbon Dioxide)
- B. $CH_4$ (Methane)
- C. $N_2O$ (Nitrous Oxide)
- D. CFCs (Chlorofluorocarbons)
Greenhouse Gas Warming Order
The correct answer is derived from Option C, indicating the order: $C < D < B < A$.
This translates to the increasing order of warming effect:
$N_2O < CFCs < CH_4 < CO_2$
Rationale for the Order
This specific ordering considers the combined effect of Global Warming Potential (GWP), atmospheric lifetime, and concentration of each gas:
- $N_2O$ (C): Has a significant GWP and lifetime, but its overall contribution is ranked lowest among these four in this context.
- CFCs (D): Possess extremely high GWPs but are present in very low concentrations. Their total warming impact is placed above $N_2O$ but below $CH_4$ and $CO_2$.
- $CH_4$ (B): Methane has a higher GWP than $CO_2$ per molecule and a substantial warming impact, greater than $N_2O$ and CFCs.
- $CO_2$ (A): Due to its high atmospheric concentration and long persistence, Carbon Dioxide causes the most significant overall warming.
Thus, the sequence $N_2O < CFCs < CH_4 < CO_2$ represents the increasing amount of extra warming.
