Answer: True
Methane (CH4) and nitrous oxide (N2O) are indeed greenhouse gases that are present in the atmosphere at naturally occurring levels. While they are found at much lower concentrations compared to carbon dioxide (CO2), both gases contribute significantly to the greenhouse effect.
To understand this better, methane is produced from natural sources such as wetlands, termites, and the ocean. Although the concentration of methane in the atmosphere is relatively low, it is much more effective than carbon dioxide at trapping heat, having a global warming potential many times greater than that of CO2 over a short timespan.
Nitrous oxide, on the other hand, is released from natural processes such as soil microbial activity and oceanic processes. Like methane, its concentration is low, but it also has a potent warming effect, contributing to global warming even at these low levels.
In summary, while these gases are naturally occurring and present in small amounts, their efficiency in trapping heat makes them significant contributors to the greenhouse effect.