Question

Which of the following are ways that humans increase the amount of greenhouse gases in the atmosphere? Check all that apply.

burning fossil fuels

deforestation

livestock

death of organisms

landfills

agriculture

sewage treatment

Answer 1

Select all except "death of organisms":

- burning fossil fuels — yes (releases CO2 and other GHGs)
- deforestation — yes (less CO2 uptake and carbon release from burning/decay)
- livestock — yes (ruminants and manure emit methane; manure and feed practices also release N2O)
- landfills — yes (anaerobic decomposition produces methane)
- agriculture — yes (rice paddies, fertilizer use and soil management emit CH4 and N2O)
- sewage treatment — yes (anaerobic treatment and sludge decomposition produce CH4 and N2O)

"Death of organisms" by itself is a natural decomposition process and not generally listed as a direct human activity that increases greenhouse gases (unless tied to human-caused mass die-offs or disposal practices).