top of page



Asking questions is often the first step to discovery. Discover the science behind Maine's changing climate through these frequently asked questions.​ Go to the topic page of each question to find videos, articles, resources and more suggested topics. 

What is climate change?

While the term weather describes the short-term conditions outside at any given time and place, the term climate describes the longer-term view over large areas. For example, Maine has a warmer and dryer climate in the summer than in the winter. Climate change is exactly that, changes in the patterns we expect from monitoring the climate over many years. Scientists use a variety of methods to track changes in the climate over time , from measuring temperatures and ice loss from glaciers, to using mathematical models to predict changes in the future. The term global warming refers to the heating of the planet’s climate since around 100-150 years ago directly due to the activities of humans.

Screen Shot 2023-01-24 at 11.07.51 AM.png


What is driving climate change?

Our changing climate is mainly due to the  burning of fossil fuels (oil, gas, coal) for energy which releases carbon dioxide and other greenhouse gasses into the atmosphere, where they trap heat, changing the Earth’s climate. Burning fossil fuels also has many other negative effects on the planet such as producing pollutants, damaging ecosystems, and impacting human health.



What are greenhouse gas emissions?

Greenhouse gasses are gasses that trap heat in the atmosphere much as a layer of glass or translucent plastic traps heat in a greenhouse used for growing plants.  The term greenhouse gas emissions typically refers to gasses that are released from anthropogenic (human-influenced) sources, such as the burning of fossil fuels.

What are greenhouse gas emissions_ 2 (pexels).jpg


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. 



What is a carbon footprint?

Carbon footprint is a way to express our personal contribution to the earth’s carbon budget. The size of our carbon footprint depends upon the amount of greenhouse gas emissions that are released into the atmosphere as a result of our routine activities and practices – our daily commute, how far and how often we choose to travel and mode of transportation we choose to travel by, the food we eat, the food we waste, the clothes we buy, the type of lightbulbs we use, everything we throw away, and more. The larger our carbon footprint, the more we are personally contributing to climate change.  Individuals, families, communities, businesses, cities and countries all have unique carbon footprints.



What is climate change acceleration?

Maine, the United States of America, and the planet are experiencing a 'great acceleration' in the changing climate. Temperatures have been rising more rapidly and the speed of sea level rise has increased. Biological diversity and ecosystem health across the world have also been deteriorating more rapidly. The newest models projecting the impacts of feedback loops suggest that even more drastic accelerations will occur in the future. The great acceleration and these more dire models highlight even more starkly the need for serious action in reducing our use of fossil fuels.



Wabanaki lifeways are inextricably linked to local landscapes and ecology and profoundly connected to major waterways and tributaries. Cultural identities and meaning are reflected in the place-based relationship expressed  through the Native languages and intergenerational knowledge handed down through family and kinship ties (see Figure 3).  The ability to participate in cultural activities, such as language use and the passing down of environmental knowledge and wisdom from elders and traditional harvesters enable the holistic relationship with the natural world that has existed for countless generations.



Tribal environmental experts have reiterated throughout discussions on climate  changes that scientific ecological knowledge (SEK) may help explain some of the historic  events of climate changes.  However,  modern scientists must also listen to native science (TEK) to fully understand shifts in the ecology, anthropogenic landscape changes, water quality, water runoff and anthropogenic concerns of pollution, fisheries, invasive species and the impacts of increasing temperatures on wildlife and forestry.

5. InvasiveMilfoil_SU.png


The tribal regions include three separate temperate zones in Maine. The Wabanaki tribes include the Maliseet and Mi'kmaq located respectively in Houlton and Presque Isle in northern Aroostook County, the Passamaquoddy located in Perry and Princeton in the Downeast Maritime regions of Washington County, and the southern tribe of the Penobscot located in Old Town in the lower regions of Penobscot County.

6. WabanakiMap.jpg


Nearly 60% of tribal households practice mixed (contemporary-traditional) subsistence lifestyles that involve hunting, fishing and harvesting culturally important species as well as wage labor in the larger economy (Houser et al., 2001). The overall increase in temperatures in the State has posed many problems with subsistence harvesting.



Paramount in the mitigation for climate changes has been the anticipated arrival of the  Emerald Ash Borer (EAB) into the region and the engagement of primary stakeholders  within the State. Particularly, the involvement of traditional harvesters and basketmakers has been essential in examining those anticipated changes and the impacts being observed. Access to Brown Ash has also been exacerbated by the loss of habitat and private land ownership. Culturally, the lack of access for harvesting challenges the transfer of traditional ecological knowledge of the species through the indigenous languages to younger generations. 

10. EAB-ExitHoles_DH.jpg


Forestry has been a major economic indicator for tribal solvency and resiliency for  decades. The identification of multiple factors of environmental changes on forestry  operations included increasing temperatures, especially during winter months, invasive species (emerald ash borer and spruce budworm), uncertainty and unpredictability for the future markets for tribal forestry products, and the long-term economic impacts for tribal forestry products due to ecological impacts of the migration and distribution of important tree species. Extreme precipitation events in the spring make road systems impassable due to muddy conditions for longer periods, delaying the opening up of tribal lands for management purposes and harvesting activities. During the fall, freeze-thaw conditions and extreme precipitation events have also led to muddy conditions and reduced access to logging operations for tribal members. 



What are the climate impacts on hydrology and Wabanaki culture?

Hydrological issues are a primary concern for the Maliseet of Aroostook County in Houlton, Maine. Observations from water quality experts at Maliseet that indicate a sharp rise in nighttime low temperatures have serious implications on the status of cold-water fisheries. Prevailing stress factors for salmon and trout survival with increased water temperatures are compounded by loss of critical habitat from historical logging operations, physical barriers from hydropower dams, early winter runoffs, decreased oxygen levels, rising pH, and toxic runoff from agriculture after extreme precipitation events. Compounding the risk of extinction of these culturally important species is the lack of state regulatory enforcement and monitoring of agricultural practices for water quality. Excess nutrients combined with warmer water appears to have made algae growth more prevalent in the Meduxnekeag River, tributaries and streams, and sedimentation due to agricultural runoff has built up in the deep pools, damaging prime habitat for the fisheries.

15. SweetgrassHarvestCoastalArea_DS.jpg


How is Sea-level Rise effecting tribal communities? 

Sea level rise and salt water intrusion into the Passamaquoddy community  infrastructure and private homes is a major concern. Historic sacred sites are at risk of being lost along coastal regions. Due to sea level rise, the water treatment facility at Sipay’k (Pleasant Point) is at risk from inundation by salt-water intrusion leading to contamination of shellfish in surrounding areas. Coastal erosion and storm surges pose significant public health concerns and potential structural damage to the facilities. The tribe will need to meet these climate-driven demands to rebuild the infrastructure and/or move the community back away from the coastline due to erosion issues, salt-water intrusion and drinking water contamination.   

16. PleasantPoint5FeetSLR_NOAA.png


There has been an overall concern about the resiliency of the ocean environment and the Passamaquoddy ocean culture in the region.  Species abundance, productivity and  biodiversity has dwindled sharply over the past 40 years.  Observations indicate a disruption in species return and migratory patterns in the marine environment.  Various fish species returning to the area have been unpredictable (earlier or later). The impacts are significant and include a disruption in the food webs, species survival and the commercial economy in which fish runs may be missed because of unpredictable seasonal conditions.  Tribal harvesters are no longer able to utilize the marine sea life for mixed subsistence practices due to a lack of access through regulation, loss of habitat and lack of species abundance, and geographic restrictions of the reservation. 

17. HarborPorpoiseGOM_NOAA.png


How are wild berry habitats shifting because of climate change?

Climate Change indicators for the wild berries described by traditional harvesters in 2015 include a loss of habitat due to shading from increased canopy cover and weed pressure, loss of traditional harvesting sites due to development, lack of controlled burns, extreme precipitation, lack of adequate snow cover, increasing freeze/thaw conditions, invasive insects, runoff, pollution, and pesticide spray on power transmission corridors. These factors are accompanied by the decline of knowledge transfer and language due to the loss of  harvesting practices and traditional values. Warm springs and warmer fall temperatures  can decrease berry yield and the storage qualities of cranberries. Overgrowth in weeds and brush create competition and decreased yields by shading out the cranberry plants which require full sun to thrive, and potentially shading the sphagnum moss which creates the necessary acidic pH requirements for optimal cranberry growth. 

19. BigMusquash2_SU.png


Tick pressure on deer populations and on the “ghost moose” has been on the rise as a result of winter infestation. The increase in tick incidences has led to the deterioration of moose health due to blood loss and loss of fur that maintains thermal insulation of this culturally important species and Maine icon. Deer and moose have been a primary food source for many tribal hunters and their families during the winter months. This reliance is threatened by an overall increase in mortality rates of the female moose along with a decrease in reproductive capacity due to anemia. As many as 5,000 ticks have been counted on a recent kill by indigenous hunters.



Is Maine's weather being impacted by climate change?

‘Climate’ is the patterns of temperature, precipitation, and other meteorological phenomena of a specific region averaged over a long period of time, while ‘weather,’ referring to short term atmospheric conditions, is what we all experience on a daily basis. Weather is when we say ‘It is cold today’ which is a short term condition and climate is when we say ‘Maine summers are usually moderate in temperature’ which is a long term average condition. A changing climate means that we should also expect to experience weather conditions here in Maine that were not at all common in the past...



In addition to Maine winters becoming warmer, fluctuations between freezing and thawing conditions are becoming more common, with heat waves and rain in the depths of winter, cold snaps and snowstorms in the spring and fall, and Arctic blasts triggering severe snowstorms in the midst of otherwise mild winters. This phenomenon is known as  “winter weather whiplash.” 

Impacts on Maine’s Weather 1 (pexels).jpg


Will drought incidence increase in Maine?

With an annual average of more than 45 inches of precipitation, Maine is often considered a state with abundant water. Nonetheless, Maine experiences dry periods and episodes of drought, sometimes resulting in major impacts on agriculture (such as the potato and blueberry industries), water resources and communities. The years-long drought in the 1960s had a major impact on agriculture and other aspects of Maine’s economy, as did the much shorter but intense drought of the summer of 2016. We saw similar impacts from the summer 2020 drought.  Rivers, such as the Piscataquis seen here, ran very low, and groundwater levels fell making Mainers’ wells more susceptible to drying up. 

Climate change acceleration 1 (pexels).jpg


Are forest species expected to change?

Because the species composition of forests in a region is largely determined by temperature and moisture, forests around the world are already changing as these two key climate factors shift. In northern New England, for example, American beech is increasing and sugar maple, red maple, and birches are declining. Most projections for the future predict that spruce and fir, which are more northern species, will become less abundant, and more southern species, such as oaks, hickories, and white pine will become more abundant across the state – much like 8,000 years ago...

Screen Shot 2023-01-26 at 2.26.25 PM.png


How will climate change effect forest physiology?

Climate change will alter temperature, moisture, snowpack, growing season, and much more, all of which will affect the physiology of trees and functioning of forests. These fundamental impacts–on tree photosynthesis, water exchange, and growth–underlie how forests will change, for better or worse, in terms of their ability to take up and “sequester” carbon, provide wildlife habitat, and produce economic benefits. Sequestering (or storing) carbon is a critical aspect of solving the climate crisis: when forests store carbon in their plants and soils, they are keeping carbon dioxide (CO2) out of the atmosphere.

Screen Shot 2023-01-26 at 2.26.16 PM.png


How will the forest product industry will need to adapt to climate change?

Changes in Maine’s climate and forests will present challenges to the industry. The industry depends to some extent on harvesting on winter days when the ground is frozen and less subject to damage from heavy machinery. A reduction in such days has already been documented in Wisconsin, a state with climate and forests similar to those in Maine. Accommodating these kinds of operational changes will increase the cost of harvesting, unless alternative approaches are developed.



How will climate change effect Maine's lakes and ponds?

When asked which attributes people value most about Maine lakes, ‘clear, clean water’ is always high on the list. However as the period of ice cover on Maine lakes shortens, lake water temperatures become warmer and the frequency of extreme weather events increases, enhancing the conditions for more turbidity, more algal growth and browner (more tea-colored) water.

Kezar Lake_RHill.JPG


How will climate change effect Maine's streams and rivers?

Increased precipitation and more intense rain events mean more stormwater runoff flooding into streams and rivers resulting in flash flooding. Flash flooding may not only erode streambanks and undermine culverts, threatening roads and other nearby human infrastructure, but also may wash soils, nutrients, and other pollutants from the watershed into streams and rivers. Fine eroded soil particles, such as silts and clays, may be carried into streams through this process, burying cobble and gravel habitat that is essential for many stream-bottom dwellers such mayfly larvae and crayfish. Since many of these invertebrate bottom-dwellers are, in turn, food for fish such as brook trout and salmon, impacts from a single climate-driven flood event may ripple through the entire stream food web.

East Outlet River_RHill.JPG


How will climate change effect Maine's wetlands?

Altered hydrology and rising temperature can both negatively impact wetlands. For example, wetlands that become dry or flooded may not only lose their capacity to purify surface water, but they may also begin to have the opposite effect: decomposing and releasing nutrients into surface waters. If plants decompose faster than they grow through photosynthesis, wetlands may cease to function as a sink for CO2  and become sources of CO2.

Climate change will affect Maine’s rivers, lakes and wetlands 2 (all trails)..jpg


How will climate change effect Maine's animal species?

Conditions will become too warm, with insufficient snow for some of Maine’s most iconic species such as Canada lynx (pictured below), moose, loons, and eastern brook trout, boreal chickadees, and Atlantic puffins. Species that are able to, will migrate northward  to find more suitable habitat. Less adaptable and/or less mobile northern species may not survive the challenge. For example, deep snow is prime habitat for snowshoe hares.  Hares, in turn, are primary prey animals for Canada lynx.  As climate change reduces the amount of snowfall in Maine, habitat for snowshoe hares will degrade, reducing their numbers.  The loss of a primary food source will pose a major challenge for Canada lynx, already Federally listed as a “threatened species.”

Impacts on wildlife and biodiversity Canada Lynx pg 32.jpg


How will climate change effect Maine's plant species?

An example of a less adaptable plant that may be negatively impacted by climate change is Furbish’s lousewort (pictured below), a plant with very specific habitat requirements and federally listed as a very rare, endangered plant species.  In Maine, Furbish’s lousewort is found only in Aroostook County, along the St. John River.  The plants require sloped riverbanks which are damp, but not too close to the water, and also partially shaded at the forest edge.  The open habitat required of Furbish's lousewort is maintained by the yearly scouring of the river ice.  As river ice diminishes, this scouring may not occur as regularly, allowing heartier species to become established, thrive, and eventually overcome the more finicky Furbish’s lousewort. 



What invasive species will Maine's changing winters bring?

In areas where winter has historically been consistently cold, such as Maine, minimum winter temperatures are tremendously important biologically, providing natural protection for native plants and animals (including us!). As growing seasons shift and the climate warms, plants and animals, including invasive species, that were once prevented from becoming established here due to Maine’s cold winters, will no longer be constrained. This climate-driven range expansion is already happening (e.g. think deer ticks and possums) and the implications for all of Maine’s native ecosystems are very serious.

Climate change in Maine 3 (pexels).jpeg


How are aquatic plants species being effected? 

Invasive aquatic plant species such as water hyacinth (Eichhornia crassipes) and water primrose (Ludwegia grandiflora), for example, once thought to pose minimal threats to Maine’s lakes, ponds and rivers due to their cold-intolerance, are both expected to be able to thrive here within a few decades. According to scientists at UMass Amherst and UNH there are hundreds of other new plant species (both terrestrial and aquatic) headed our way. Not all will pose serious risks to Maine’s native ecosystems and economy, but as the climate shifts, we can certainly expect the list of plant species that do pose such risks, to grow significantly.



How are climate-driven invasive pests impacting agriculture in Maine?

Climate-driven invasive pests are also impacting agriculture. The spotted wing drosophila (Drosophila suzukii) is a small, fruit-fly-related invasive insect of Asian origin that can cause devastating impacts on cultivated (and wild) berry and stone-fruit crops.  Spotted wing drosophila (SWD) were first spotted in Maine in 2011 and can now be found throughout the state, though currently their highest numbers are in coastal and southern areas.

Invasive Species Spotted Winged Drosophila pg 34.jpg


How could invasive marine species impact Maine's commercial fish species? 

According to the Gulf of Maine Research Institute, changes to ocean temperature and circulation could modify the habitats of more than three-quarters of target commercial fish species in the Gulf of Maine, allowing new, invasive species to enter the region.

Green Crab invasive species_edited.jpg


What is ocean acidification?

Burning fossil fuels not only results in more carbon dioxide in the air but also in our ocean. The chemical balance of the ocean is delicate, and this increase in carbon dioxide alters that balance resulting in increased acidity known as acidification. While this acidification has no direct impact on our own health, it does harm the growth of many of the organisms that play key roles in the marine ecosystem such as shellfish, corals and certain fish. Ocean acidification also has implications for the very young life stages of some creatures that support many other animals such as whales and seabirds.

Screen Shot 2023-02-01 at 4.15.55 PM.png


Will coastal communities be impacted by rising sea levels?

Melting ice in the Arctic is leading to rising sea levels around the world. While an increase of around one tenth of an inch per year does not sound like much, the 7.5 inch increase in sea level since 1912 (recorded in Portland) is responsible for increasing erosion and flooding along the coastline. This can result in the potential loss of sandy beachfront, coastal wetlands and salt marshes.



Why will tourism in Maine be adversely impacted by climate change?

Because Maine tourism depends so much on nature, climate change will have an impact on many of these activities. For example, the season and opportunities for skiing, ice fishing, and snowmobiling will decrease, but the camping and hiking seasons will lengthen. Some of Maine’s iconic wildlife, such as moose, brook trout and loons, which attract visitors to the state, may be harder to find.

Economic impacts 4 (pexels).jpg


Will unreliable Maine seasons impact winter recreation?

Skiing, snowmobiling, and dog sledding all rely upon snow (both natural snowfall and temperatures cold enough to make snow).  But according to long-term measurements from the Hubbard Brook Research Foundation in the White Mountain National Forest, the region is seeing increased average winter air temperatures, less snow, more sleet and freezing rain.

Economic impacts 5 (pexels) (2).jpg


How will fishing and hunting in Maine be impacted by climate change?

Extreme weather and warmer temperatures linked to climate change will negatively impact a number of Maine’s long held outdoor traditions such as fishing and hunting.

Economic impacts 3 (pexels).jpg


How will hiking and backpacking be effected?

Hiking and backpacking in Maine will be increasingly threatened by wildfires, drought, more excessively hot and humid weather, and other factors that will limit both the hiking experience and the stewardship of trails. 

Economic impacts 2 (all trails).jpg.jpg


How will Maine farmers, gardeners and consumers be effected by climate change?

While predictable weather forecasts are critically important to growers, a changing climate presents meteorologists and farmers with unprecedented challenges from less predictable weather patterns to new unseasonable extremes.

How can we reduce greenhouse gas emissions and other air pollutants_ 5 (pexels).jpg


What will the impacts on wild crops such as blueberries and maple syrup be?

Recent research conducted out of the University of Maine suggests that wild blueberry fields have been warming at a rate that could have negatively impacted crop health and yields. Down East barrens, which seem to be reacting to climate change faster than the state as a whole, may be especially vulnerable.  According to the researchers,  blueberry plants cannot photosynthesize well at temperatures that consistently exceed 72 degrees Fahrenheit. The fact that Maine has reported record-high temperatures over the past few years could see blueberry yields struggle in the future.

Impacts on Maine farmers, gardeners and consumers 1 (pexels).jpg


Has climate change put Maine's commercial fishing, lobster and shellfish industries at risk?

Maine’s long standing lobstering heritage is at risk due to warming of coastal water temperatures. The recent boom in lobstering over the last six to eight years may seem to contradict this. However, this increase in the lobster population is temporary as it is due to the northward migration of lobsters from the south. As lobsters continue their northerly migration, soon it will be Maine’s turn to watch them disappear.

Impacts on Maine farmers, gardeners and consumers 5 (pexels).jpg


How will climate change damage Maine's infrastructure and property values?

The Northeast has experienced a greater recent increase in extreme precipitation than any other region in the U.S. Between 1958 and 2010, the Northeast saw more than a 70% increase in the amount of precipitation in very heavy rainfall events, taxing an already stressed and aging infrastructure. Flood conditions created by increased precipitation, more frequent extreme precipitation events and wild temperature swings are all threats to public infrastructure such as roads and bridges, and private property.



How does climate change increase the risk of tick-borne disease?

As Maine warms and winters become milder, it becomes more hospitable for migrating pests from the south. Deer ticks carry Lyme disease, and as tick populations increase and the season for encountering ticks expands, so does Lyme disease incidence in Maine.

Climate change in Maine 4 (pexels).jpg


How does climate change increase the risk of mosquito-borne disease?

West Nile Virus (WNV) is a mosquito borne viral disease. It is transmitted to a person through the bite of an infected mosquito. As temperatures rise in Maine mosquito season extends past the summer months meaning longer breeding seasons and increased hatch rates. This leads to an increase in the chances of transmission.

Impacts on Maine’s public health 2 (pexels).jpg


How is drinking water being impacted in Maine?

Roughly 50% of Maine people get their drinking water from public water utilities drawing water from surface water sources (primarily rivers and lakes) and/or groundwater aquifers. Communities that draw water from surface water sources will face new challenges as lakes warm and become increasingly prone to  harmful (toxic) algal blooms, cultural eutrophication and invasive aquatic plant infestations.



How is the climate crisis related to self care, mental health and well being?

As more and more people become aware of the reality of climate change and the urgency of the situation, an increasing number of people from around the world are experiencing anxiety, depression and grief related to the climate crisis (termed: climate grief, climate anxiety, or eco-anxiety). In September 2021, the biggest study yet on the mental health impacts of climate change surveyed 10,000 people, ages 16 to 25, from 10 different countries on their thoughts and feelings about climate change. An overwhelming number of respondents reported worry and over half reported feeling anger, sadness, or guilt connected to the climate crisis. Over 45% shared that these feelings have a significant negative impact on their daily lives. And while people of all ages report many of these feelings in connection with climate change, the experiences seem especially prevalent in young people.




The Maine Climate Science Portal was envisioned and developed by Maine Climate Action Now. Content development, to date, has been a largely-volunteer effort. Click here to see a full list of contributors.

Do you have feedback on this resource? Share your feedback in this form.

bottom of page