Greenhouse gas emissions are gases that trap heat in the atmosphere, contributing to climate change. The most important greenhouse gas emitted by humans is carbon dioxide (CO2), which is produced by burning fossil fuels such as coal, oil, and natural gas. Other greenhouse gases include methane (CH4), nitrous oxide (N2O), and fluorinated gases (F-gases) . Greenhouse gas emissions are measured in CO2 equivalents, which depend on their global warming potential (GWP) and their lifetime in the atmosphere.
Human activities are responsible for almost all of the increase in greenhouse gases in the atmosphere over the last 150 years. The largest source of greenhouse gas emissions from human activities in the United States is from burning fossil fuels for electricity, heat, and transportation. Other sources of greenhouse gas emissions include agriculture, land use, and industrial activities.
The main greenhouse gases and their sources are:
- Carbon dioxide (CO2): emitted by burning fossil fuels, deforestation, and other land-use changes.
- Methane (CH4): emitted during the production and transport of coal, natural gas, and oil, as well as from livestock and other agricultural practices, land use, and the decay of organic waste in landfills.
- Nitrous oxide (N2O): emitted during agricultural, land use, and industrial activities, combustion of fossil fuels and solid waste, and treatment of wastewater.
- Fluorinated gases (F-gases): emitted from industrial processes such as refrigeration and air conditioning.
Reducing greenhouse gas emissions is crucial to mitigating the impacts of climate change. This can be achieved by phasing out fossil fuels and transitioning to renewable energy sources such as solar and wind power.
