Climate Change Program

The main cause of climate change is human activities, particularly the emission of greenhouse gases (GHGs) into the atmosphere. The Maryland Department of the Environment (MDE) is leading Governor Hogan's efforts to reduce GHG emissions and adapt to the potential consequences of climate change while creating jobs and benefiting the economy, as required by the Greenhouse Gas Reduction Act (GGRA) of 2009 and 2016. Although many initiatives throughout the State contribute to these efforts, the Regional Greenhouse Gas Initiative (RGGI) and the Maryland Commission on Climate Change (chaired by Secretary Ben Grumbles) are key efforts by MDE, each of which can be explored further by following the links on the left-hand side of the page.

With 3,100 miles of shoreline, Maryland is one of the states potentially most vulnerable to sea-level rise associated with climate change. Rising sea levels and increased storm intensity could have devastating and far-reaching impacts on the Atlantic coast and the Chesapeake Bay ecosystem that affect the environmental, recreational and economic benefits enjoyed by Maryland and its visitors. Although Maryland's coastal areas may be considered particularly vulnerable, all areas of the State are at risk, and may already be experiencing some impacts of climate change. In general, climate change is expected to alter the severity, frequency or distribution of existing issues which are impacted either directly or indirectly by temperature and precipitation. This includes, but is not limited to:

  • Impacts on coastal, bay, and inland water quality parameters that may change the viable uses of surface water, such as for irrigation, recreation, or human consumption;
  • More frequent disruptions to urban and coastal infrastructure in Maryland caused by extreme weather events and sea-level rise that may indirectly impact the economy of the region by restricting the flow of goods and affecting days worked;
  • Common stressors experienced among ecosystems, agriculture, fisheries and forestry such as those caused by general changes in temperature and precipitation regimes; increased extreme weather events; and increased pressures from weeds, diseases, and pests;
  • Human health issues, including those affected by impacts on food and water supply, air quality and extreme weather events; and
  • A higher probability of negative outcomes for individuals and communities inherently more sensitive or with a reduced adaptive capacity for responding to the impacts of climate change.
To learn more about climate change and what Maryland is doing to combat it, visit the Climate Change Reports page. For a national perspective, visit the U.S. Environmental Protection Agency (EPA) website on Climate Change in the United States

Maryland's Greenhouse Gas Emissions Reduction Act (GGRA)

In 2009, Maryland adopted the Greenhouse Gas Emissions Reduction Act of 2009 (GGRA). The law requires the State to reduce GHG emissions 25 percent from a 2006 baseline by 2020, in a way that ensures positive impact on Maryland's economy, protects existing manufacturing jobs and creates new jobs in the State. MDE's 2015 GGRA Plan Update showed that Maryland was on target to not only meet but exceed this level of emissions reduction; with an estimated economic benefit between $2.5 and $3.5 billion in increased economic output by 2020 as well as creation and maintenance of between 26,000 and 33,000 new jobs. In 2015, Governor Hogan signed an updated version of the law, which includes the same balanced requirements and safeguards as the original, such as additional reporting and a mid-course reaffirmation of goals by the Maryland General Assembly, as well as incorporating protection for jobs and the economy. The most significant enhancement was a new benchmark requiring a 40 percent reduction of emissions from 2006 levels by 2030. This additional benchmark was included in order to ensure continued progress after 2020 toward the State's long-term GHG emission reduction goals.

MDE is currently working on a draft of the 40 by 30 plan, which is due to be presented to the Governor and the Maryland General Assembly at the end of 2018. The final plan must be adopted in 2019 and has the same requirements as the 2012 plan, including consideration of the impacts implementation may have on all segments of the community (rural, low-income, minority) as well as various sectors of the economy (agriculture, manufacturing); ensuring reliable and affordable electrical service; producing a net economic benefit for Maryland and a net increase in jobs in the State; encouraging new "green jobs" in Maryland; and special provisions protecting the manufacturing industry. Once the draft plan is released, it will be posted for public review and comment and a number of public hearings will be held on the subject. Please visit the site at this time for additional information.

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