What are Greenhouse Gas Emissions?

Emissions are substances released into the air and are measured by their concentrations, or parts per million, in the atmosphere.

The main greenhouse gases are water vapor (H20), carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride (SF6).

These long-lived gases trap solar energy (heat) and create a “greenhouse effect” in Earth’s climate. Human activities have largely led to the high concentrations of greenhouse gases and global warming we see now.

Energy use and production, followed by agriculture, are the largest sources of emissions worldwide. Carbon dioxide from burning fossil fuels accounts for about three-fourths of current total greenhouse gas emissions.

Greenhouse Gas Emissions…

  • create conditions that cause further warming, such as higher evaporation rates and a wetter atmosphere
  • create conditions for increased ozone, smog and heat waves that worsen respiratory disease, asthma and other health issues
  • change the ocean’s chemistry through ocean acidification, making it harder for marine animals to build their shells and sustain crucial global food webs


Healthy soils can store carbon in the ground, where it belongs

Our Future with Greenhouse Gas Emissions

Some changes resulting from the greenhouse effect cannot be reversed. Consider that thousands of years from now, 20 percent of recent human-caused carbon dioxide emissions will still be in the atmosphere.

But we can curb some of the most negative impacts by decreasing greenhouse gas emissions by half for each decade from now on.

Clean technologies and energy conservation strategies have proven to be effective solutions for households, businesses and municipalities. For example, from 1990 to 2014 in the United States, increased energy efficiency and structural changes in the economy contributed to a 40 percent decline in greenhouse gas emissions per dollar of GDP. Such initiatives require political, financial and personal efforts from the public to put them into place globally.