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How can we reduce greenhouse gas emissions and other air pollutants? 

One of the most important ways to reduce greenhouse gas emissions and curb climate change is to reduce our use of fossil fuels. Because greenhouse gasses are emitted in so many different sectors of our economy, the solutions for curbing emissions will also be widely varied and widely distributed. 



  • shifting to renewable energy sources such as wind and solar; 

  • protecting and restoring natural areas such as forests and tidal marshes that ‘sequester’ large quantities of carbon;

  • protecting indigenous peoples’ rights and sovereignty, allowing traditional practices to continue—in turn protecting ecosystems and carbon sinks and preventing emissions from deforestation; 

  • shifting food systems toward regenerative forms of agriculture, plant-based diets, and the elimination of food waste; 

  • reducing consumption and creating circular economies where manufactured items are reused, recycled, upcycled and/or designed to be repairable. 

Policy solutions for reducing greenhouse gas emissions:

Policy solutions such as regulation, fees, and cap-and-trade systems can be used to advance solutions such as those discussed above, and enhance the likelihood of their success.  Under the Clean Air Act, for example, EPA implements several regulations that affect power plants, including the Acid Rain Program, the Cross-State Air Pollution Rule, and the Mercury and Air Toxics Standards. These programs require fossil fuel-fired electric generating units to reduce emissions of sulfur dioxide (SO2), nitrogen oxides (NOX), and hazardous air pollutants including mercury (Hg) and have been very effective in protecting human health and the environment.


To regulate harmful pollutants, U.S. environmental law generally takes one of two approaches. A law may mandate specific control technologies or production processes that polluters must use to meet an emissions standard.  Or it may require that polluters meet an emissions standard, but allow polluters to choose any available method to meet that standard. 


Occasionally, laws are adopted that completely ban or phase out the use or production of a particular product or pollutant, as it has done with chlorofluorocarbons (CFCs) and certain pesticides.

THE CLEAN AIR ACT is an example of a relatively successful environmental regulation.  A recent 50-year retrospective review of the Clean Air Act revealed that this comprehensive federal law outlining a wide array of regulatory mechanisms led to substantial pollution emissions reductions and health improvements in the US.  Despite the quadrupling of gross domestic product (GDP) since 1970 (GDP is generally associated with increased production) air quality across the United States substantially improved during this period.  The decline in pollutants and increase in GDP since 1980 are shown in the chart below.

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Fees, charges, and taxes are policy solutions intended to provide monetary incentives for polluters to reduce the overall quantity of a given pollutant, or to limit public use of a scarce natural resource. Fees have been used successfully to curb water usage in times of drought, and to limit wastewater discharge into waterways.

CITIZENS' CLIMATE LOBBY'S carbon fee and dividend proposal is a good example of how fees may be used to limit greenhouse gas emissions. CCL supports an economy-wide carbon fee program, where the funds raised through the program are equitably distributed back to American households in the form of a ‘dividend.’  Under this program, a fee is levied per ton of potential carbon emissions, and would be applied wherever fossil fuels enter the economy. The dividends received by all American households would help offset inevitable price increases, especially on emission-heavy products. The price increases and dividends would flow through the economy, incentivizing businesses and people to switch to clean energy.  The primary drawback with fees, charges and taxes is that this form of policy solution cannot guarantee a specific amount of pollution reduction as would be the case with strict regulation or a regulated phase-out.


A cap-and-trade system is another market-based approach to control pollution, in this case by providing economic incentives for reducing the emissions of pollutants. Under this policy solution, a central authority or governmental body determines how many units of a certain pollutant may be safely emitted if desired goals are to be achieved. The authority then ‘caps’ emissions units at that level. Total allowable emission units are then divided up between a limited number of permits. These permits are then allocated among polluters, each permit allowing the discharge of a specific quantity of units of a specific pollutant over a set time period. If polluters wish to increase their emissions beyond the unit limit of their permit, they must buy emission units from other polluters in the program who are able and willing to sell them. Cap and trade programs are considered to be more flexible than traditional forms of regulation as they allow organizations and markets to decide how best to meet policy targets.

THE REGIONAL GREENHOUSE GAS INITIATIVE (RGGI) is the first mandatory cap-and-trade program in the United States to limit carbon dioxide from the power sector. Eleven states currently participate in RGGI: Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, Virginia.


Divest from Fossil Fuels


LD 99 | An Act To Require The State To Divest Itself Of Assets In The Fossil Fuel Industry, became STATUS: law as of June 16, 2021

DISCOVER MORE | Suggested topics


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