Climate Change:
High Global Warming Potential Gases
What are the high GWP gases and where are they used?
The high global warming potential (GWP) gases include hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6). HFCs and PFCs are used as substitutes for the ozone-depleting chemicals that are now restricted under the Montreal Protocol of 1987. These gases are used in a wide range of manufacturing plants and consumer products such as:
- Automobile air conditioners
- Refrigerators
- Propellants in certain consumer aerosol products, for example: aerosol paint, personal care products, tire inflators, party spray (foam strings), air horns
- Spray foam insulation and other foams
- Fire extinguishing
- Tennis balls
- Electric power transmission
Emissions of these chemicals are a result of human activities. They are released as a result of their direct use or unintentionally as an industrial byproduct.
Source: US EPA 2012 Greenhouse Gas Inventory Report
High GWP gases make up a small portion of the total US greenhouse gas emissions. They are, however, very potent and long lived.
Source: US EPA High GWP Gases and Climate Change, 2011
These gases are very stable in the atmosphere. They can remain there for many years. Therefore, concentrations and impacts of these gases in the atmosphere will increase as long as emissions of these gases continue.
Why be concerned about high global warming potential GWP gases?
Certain gases trap heat in the atmosphere and, as a result, have the potential to contribute to climate change by raising the temperature in the atmosphere. Carbon dioxide (CO2) is the best -known and most common global-warming gas. It has been assigned a “global warming potential” of 1. Other greenhouse gases are assigned a GWP relative to CO2. The chart below shows the assigned GWP of a few important greenhouse gases.
Source: IPCC Fourth Assessment Report, Working Group I: The Physical Science Basis TS2.5 Net Global Radiative Forcing, Global Warming Potentials and Patterns of Forcing, 2007
Some gases have the potential to trap a much greater amount of heat in the atmosphere than CO2 does. For example, PFC-116 can trap 12200 times more heat in the atmosphere than CO2 over a 100-year period. This means that relatively small amounts of these gases in the atmosphere have large impacts.
In 2007, the Minnesota Legislature passed into law the Next Generation Energy Act. The law specifies the development of a comprehensive plan to reduce Minnesota’s emissions of greenhouse gases.
A high GWP gas reporting statute was passed in May 2008 as part of the Energy Omnibus bill (Minn. Stat. § 216H.11).
High GWP Reporting Requirements
As a result of Minn. Stat. § 216H.11, Minnesota is taking a number of steps, including collecting information about certain high GWP gases and their uses.
- Automobile manufacturers report to the MPCA the amount of refrigerant that leaks from air conditioners used in passenger cars, trucks and SUVs. This applies to new vehicles sold on or after January 1, 2009. Reporting forms are available on the Mobile Air Conditioner Web page. The MPCA will post the mobile air conditioner leakage rate results on its web site in early 2009.
- Manufacturers of these chemicals report to the MPCA the amount of high GWP gases that they sell annually in Minnesota. The report for sales made in the previous year is due by October 1 of the current year. Submit completed forms to hgwp.pca@state.mn.us.
- Purchasers who buy more than 10,000 metric tons (CO2-equivalent) of any one high GWP gas annually have to report purchases of all high GWP chemicals. The report for purchases made in the previous year is due by October 1 of the current year. Submit completed forms to hgwp.pca@state.mn.us.
Table of HFCs and PFCs and Pounds of Chemicals that Trigger Reporting RequirementsFor further information, contact Azra Kovacevic at 651-757-2505.
Where can I find more information about high GWP gases or climate change?
- National Oceanic and Atmospheric Administration (NOAA), National Climatic Data Center - Frequently Asked Questions (FAQs)
- US EPA Climate Change and High GWP gases Web pages:
- MPCA’s climate change Web page
- Reports on Reducing Potential Climate Effects of Emissions of Non-CO2 Greenhouse Gases:
