Climate Change in Maine

From increasing land and ocean temperatures, to rising sea levels, more frequent severe storms, increased environmental damage, and public health maladies, Maine scientists are cataloging the significant effects of rising greenhouse gases and climate change on our state.

Greenhouse Gas Emissions

Greenhouse gas emissions are a central cause of climate change. In Maine, most emissions come from transportation, followed by residential, commercial and industrial sources. Finding ways to reduce them is a key goal of the Climate Council.

Maine greenhouse gas (GHG) Emissions by sector




Electric Power







Maine's greenhouse gas emissions over time


Climate Change Effects


Rising Temperatures

  • Maine’s annual temperature has increased 3.2 degrees F since 1895, and extreme heat days are expected to be two to four times more frequent by 2050.
  • Warming has shortened Maine’s winters and lengthed the summers by two weeks on average over the last century, a trend that’s expected to continue as temperatures increase.
  • Warming winters reduce snowpack and change snowmelt, river, and lake ice-out dates, causing ripple effects through Maine’s biodiversity, agriculture, inland lakes and streams, and winter-based recreation.
  • Recent “ocean heat waves” have occurred in the Gulf of Maine, which is warming faster than 99 percent of the world’s oceans and is beginning to lose its subarctic characteristics.
boat in a harbor

Environmental damage

  • By 2050, Maine will likely see between 1.1 and 1.8 feet of relative sea level rise, and potentially between 3.0 and 4.6 feet of sea level rise by the year 2100. A 1-foot increase in sea level in the future will lead to a 15-fold increase in the frequency of “nuisance” flooding.
  • Sea level rise will cause regular flooding of Maine’s coast and may cause saltwater contamination of groundwater aquifers. Coastal beaches, dunes, salt marshes, and bluffs are likely to experience increased erosion, landward movement and land loss.
  • Maine’s annual precipitation (rain and snowfall) has increased more than 6 inches since 1895, and extreme precipitation events (1” to 4” or more) are becoming more frequent.
  • Recurring blooms of harmful blue-green algae in Maine lakes are expected to become frequent as temperatures warm, potentially impacting human, animal, and ecosystem health.

Biodiversity impacts

  • Iconic Maine species such as moose, Canada lynx, loons, boreal chickadees, eastern brook trout, saltmarsh sparrows and Atlantic puffins are under stress from climate change.
  • Sub-Arctic and boreal marine species are disappearing from the Gulf of Maine’s traditional fishing grounds as they move northward with ocean warming, while temperate species from the south invade.
  • Ocean acidity levels have already risen 30 percent and will continue rising alongside growing greenhouse gas levels. Ocean acidification has already impacted some aquaculture operations in Maine and will increasingly affect marine organisms that produce calcium carbonate to build shells, such as oysters, scallops, clams, mussels, and sea urchins.
  • Extreme precipitation, changing temperatures, and other impacts from climate change are contributing to stress on Maine’s native tree species.
a tick on a person's wrist

Public health risks

  • Increased heat from climate change may put Maine people at risk, given the state’s demographics, rates of chronic disease, numerous outdoor occupations, a large rural population with limited access to health care, and limited adoption of home air conditioning.
  • Warmer, shorter winters from climate change have played a role in the increase of tick-borne illnesses in Maine, such as Lyme disease, anaplasmosis, babesiosis, and Powassan encephalitis virus.
  • Increased extreme weather may lead to additional storm-related injuries and deaths, outbreaks of waterborne diseases, carbon monoxide poisonings and food-borne illnesses following power outages, as well as mental health stress.
farm equipment

Food system impacts

  • Warming temperatures bring both potential benefits from longer growing seasons and lower heating costs, but also potential damages from heat stress to workers, crops and livestock, and greater cooling costs. Increasingly unpredictable and extreme precipitation will significantly impact Maine agriculture.
  • Food-borne illnesses may become more common as temperatures rise, from vibrio bacteria-contaminated seafood; shellfish and fish poisoning from more frequent harmful freshwater and marine algal blooms; and spoiled food from power outages caused by severe storms.
  • Acidic ocean water is already having negative effects on aquaculture, with some harvesters adding acid relief chemicals to sites to grow shellfish.
people cross country skiing

Economic impacts

  • All sectors of Maine’s economy -- from energy to agriculture, forestry, fishing, and tourism – will feel the effects of climate change, such as warmer temperatures, more rain and overall extreme weather, and rising sea levels. Sea-level rise will increase the incidence of flooding and damage to property and infrastructure.
  • Maine’s natural environment is essential to the state’s multi-billion-dollar tourism industry, which relies heavily on outdoor and recreational activities. Favorite activities of visitors – such as skiing or snowmobiling in the winter or visiting beaches in the summer – are vulnerable from rising temperatures, precipitation, and sea level rise.
  • For Maine seafood harvesters, climate change is expected to reduce not only regional catches and revenue but also have a ripple effect through county-level wages and employment. In 2018, commercial fishing employed nearly 30,000 Maine people and was valued at about $637 million.
  • Adapting to climate change does broach new economic opportunities, such as growing renewable energy sources like land- and ocean-based wind power, solar, and biofuels.
Flooded road and stop sign

What do you think about climate change?

How important is climate change to you? Are you concerned about how climate change may affect you, your family or your community? Has your opinion changed at all from recent global events?

Please take a few minutes to share your climate opinions to help the Maine Climate Council inform its work. Click the link below to begin.

Contact the Maine Climate Council

Learn More:

Data Sources:

The climate change data above were compiled by the Science and Technical Subcommittee of the Maine Climate Council to inform the draft strategies of the working groups. Click here to read their final report, Scientific Assessment of Climate Change and Its Effects in Maine (PDF). Maine's greenhouse gas emissions data come from the Department of Environmental Protection's Eighth Biennial Report on Progress toward Greenhouse Gas Reduction Goals (PDF).