Emissions originate from both anthropogenic actions and natural processes.
Natural sources of emissions encompass diverse phenomena releasing gases and particles into the atmosphere independent of human intervention.
Examples of natural sources are:
1. Volcanoes: Erupt with gases such as sulfur dioxide (SO2) and ash.
2. Forest Fires: Generate carbon dioxide (CO2), carbon monoxide (CO), and smoke particulates.
3. Dust Storms: Transport dust and fine particles across extensive distances.
4. Oceans: Release salt particles and gases like dimethyl sulfide.
5. Plants and Trees: Emit volatile organic compounds (VOCs), including isoprene.
6. Animal Respiration and Decay: Produce carbon dioxide and methane (CH4).
These natural emissions are integral to the Earth’s atmospheric equilibrium and biogeochemical cycles.