Climate change impacts the province's natural resources – its forests, water, fish and wildlife.
Learn more about the known and potential impacts of climate change on natural resources in Ontario by clicking on one of the map's call-out boxes.
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Biodiversity
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| Monarch Butterfly |
Biodiversity is the variety of life on earth. It includes all living things, and the way they interact with one another and their environment. Climate change threatens both natural ecosystems and human well-being because changing temperatures and changes in precipitation patterns can cause milder winters, storms, floods, and droughts.
In Ontario, climate change may impact biodiversity in several ways:
• There may be changes to the composition, structure and function of ecosystems.
The geographic ranges of plants and wildlife are predicted to move northward as temperature
increases.
• Species at risk and isolated habitats may be most sensitive to changes.
• Decreases in ice-cover and changes to freeze-up and break-up times may affect the food supply
for aquatic life and alter fish spawning.
• Changes in water and air temperature may make conditions more favorable for diseases and
invasive species, putting pressure on native species in the area.
Read more about the connections between climate change and biodiversity - PDF 263 Kb
The following science report explores the impacts of climate change to biodiversity within Ontario’s terrestrial ecosystems:
The Known and Potential Effects of Climate Change on Biodiversity in Ontario’s TerrestrialEcosystems: Case Studies and Recommendations for Adaptation (2007) - PDF 1.5 Mb
Wetlands
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| Fen near North Bay |
Ontario contains over one-quarter of Canada's wetlands and 6% of the world's wetlands. Wetlands help reduce the effects of climate change by capturing and storing carbon. A changing climate will alter wetlands and may affect the plant and animal species that live in wetlands.
In Ontario, climate change may impact wetlands in several ways:
• Changes in precipitation and increasing temperature may change wetland water systems
causing flooding and droughts.
• When there is a decrease in precipitation and increased evaporation due to increased air
temperatures, wetlands may dry up or disappear.
• Where moisture levels fall due to lack of precipitation and increased evaporation due to increased
air temperatures, wetlands may dry up or disappear.
• It is likely that as wetlands dry up, plants living in the area may shift. For example, marshes
may become more swamp-like as woody plants move into marsh areas.
Birds are also expected to be affected.
• Loss or degradation of wetland habitat and food availability may lead to declines in populations
of wetland dependent species such as the pied-billed grebe.
Read more about climate change and wetlands
Forests
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| Forest fire, Thunder Bay |
The Ministry of Natural Resources works with many partners to care for and manage Ontario’s forests, which encompass more than 712, 000 km2 and represent 2% of all forested land on Earth. Climate change will have a significant impact on Ontario’s forested ecosystems. Forests are also an important part of climate change mitigation by storing and sequestering carbon.
In Ontario, climate change may impact forests in several ways:
• There may be increased occurrence of insect and disease outbreaks.
• Increased tree stress may affect growth and productivity of forests.
• Drier forests will lead to more intense and frequent forest fires.
• Local tree species will be less suited to local conditions as the climate changes and may migrate
more slowly than climatic conditions, leading to changes to tree species distribution.
• Changes to tree species distribution
• Damaged and unhealthy forests will be less effective in sequestering carbon.
The following reports provide more information about the effects of climate change on Ontario’s forests and what the Ministry and our partners are doing to reduce the impacts.
• Ontario's Forests and Forestry in a Changing Climate CCRR-12 - PDF 702 Kb
• Forest Research Information Paper No. 143: The Impacts of Climate Change on Ontario’s
Forest - PDF 1.2 Mb
Water
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| Road closed due to flooding |
More than 250,000 lakes (including the Great Lakes) encompass 181,153 km2, or about 17% of Ontario. Climate change is impacting the Earth’s water balance and could affect the availability of water for human use. Climate change could also mean the potential for more extreme weather events and water-related hazards, such as flooding, drought and poorer water quality.
In Ontario, lower water levels may mean:
• Less available water supplies for domestic, agricultural, commercial and industrial uses.
• Increased demand for diversions and bulk water transfers (internationally, nationally and provincially).
• Increased conflict between water users. Less capacity to generate hydroelectric power
at peak use times.
• Decreased access to waterways, altering shipping operations and navigational routes.
• Altered flow rates at water control structures (dams etc.).
• Decreases in water quality (more micro-organisms).
In Ontario, higher water levels as a result of climate change may mean:
• Increased risk of flooding (more public safety hazards).
• Increased erosion and shoreline damages.
• Increased infrastructure failures (roads, bridges, etc.).
• Decreased water quality (due to increased runoff and debris).
Read more about climate change and water resources in Ontario - PDF 910Kb
The following report provides more detail and information on climate change and lakes and rivers in Ontario:
•Potential Changes in Future Surface Water Temperatures in the Ontario Great Lakes as a
Result of Climate Change CCRN-7 - PDF 1.9 Mb
Fisheries
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| Chinook Salmon |
In most aquatic organisms, growth and reproduction are strongly influenced by water temperatures. Fish, for example, can be separated into those that do best in cold, cool, and warm waters. Climate change driven increases in water temperatures could make some rivers and lakes unsuitable for the fish that now live there.
In Ontario, climate change may impact fisheries in several ways:
• Higher lake temperatures could result in shifts from cold water species such as lake trout, to cool
and warm water species like yellow perch and largemouth bass.
• Distributions and population sizes of some fish species may undergo dramatic changes as they
are replaced by more temperature tolerant species.
• In some cases, already threatened or endangered species such as sturgeon may disappear completely.
• Expected changes in the composition and availability of phytoplankton and zooplankton – the
primary foods at the bottom of the food web – may favour some species over others.
The end result could be a reshuffling of the organisms making up aquatic communities in many of
Ontario’s rivers and streams.
• These types of changes may make conditions more favourable for invading species like zebra
mussels and the round goby and for fish diseases such as Viral Hemorrhagic Septicemia (VHS).
The following reports provide more detail and information on climate change and fisheries in Ontario:
• A summary of the effects of climate change on Ontario's aquatic ecosystems - CCRR11
PDF 1.2 Mb
• Regional Projections of Climate Change Effects on Ontario Lake Trout (Salvelinus namaycush)
Populations CCRR–14 - PDF 962 Kb
• Key Ecological Temperature Metrics for Canadian Freshwater Fishes CCRR17 - PDF 2.7 Mb
Wildlife
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| Woodland Caribou |
Ontario is currently home to a diverse range of wildlife species. The range that any given species occupies is affected by factors including climate, weather, and competition. When wildlife habitat changes or disappears, the species that depend on it must find new ways to survive.
In Ontario, climate change may impact wildlife in several ways:
• Some species will be forced to move further north to more favourable habitat, while others in
more southern ranges will experience range contraction due to increased presence
of parasites and competition.
• While some animals will migrate and adapt successfully, species that require a narrow range
of temperature and precipitation conditions will be most likely to experience decline or extinction.
• Changes in climate may affect reproduction, predation, survival, and rate of disease in wildlife
species, as well as the availability of food and habitat. For example, migratory songbirds may be
affected by a timing mismatch in the arrival dates of the birds to their breeding grounds and the
availability of food they need for successful reproduction.
The following report provides more information on the known and potential effects of climate change on Ontario’s wildlife:
• The Known and Potential Effects of Climate Change on Biodiversity in Ontario's
Terrestrial Ecosystems: Case Studies and Recommendations for Adaptation CCRR-09
PDF 1.7 Mb
Socioeconomics
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| Fishing, Lake St. Nora |
In addition to impacting the Earth’s ecosystems, climate change will affect our daily lives in many ways, including our health and recreational opportunities. Most tourism and recreational activities in Ontario are influenced by weather, especially nature-based activities. Changing climate including extreme weather such as heat waves, high winds and poor air quality can cause serious health issues for Ontarians.
In Ontario, climate change may have many impacts on socioeconomics:
• Tourism and recreation impacts:
• It is expected that warm-weather tourism and recreational opportunities (such as
camping, canoeing, and golfing) will increase and opportunities for winter-based activities
(such as ice fishing, skiing and snowmobiling) will disappear in some parts of Ontario.
• Parks visits are projected to increase as warm-weather tourism season extends earlier in the
spring and later in the fall.
• Human health impacts may include:
• More injuries may occur due to an increase in severe weather events like floods and wind storms.
• People face an increased risk of heat stress as a result of more frequent and long-lasting heat
waves.
• There amy be increased exposure to infectious diseases and parasites (such as Lyme disease), as
well as food-born diseases.
To learn more about how Ontario’s recreation and tourism activities could be affected by climate change, read the following reports:
• Climate Change Research Report 08: Climate change and nature-based tourism, outdoor
recreation, and forestry in Ontario: Potential effects and adaptation strategies - PDF 2.4 Mb
• Climate Change and Recreational Fishing CCRR-04 - PDF 1.1 Mb
To learn more about the known and potential impacts of diseases and parasites associated with climate change, read the following report:
• Forest Research Information Paper No. 154: A Synopsis of Known and Potential Diseases and
Parasites Associated with Climate Change - PDF 5.2 Mb
To learn more about Lyme disease and its treatment and prevention, visit the Ministry of Health and Long-Term Care website.
Parks and Protected Areas
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| Campsite, Algonquin Park |
Parks and protected areas serve as sites for protection, recreation, scientific research and traditional uses. Climate change has been identified as a significant stressor that may affect these values and activities in a host of ways.
In Ontario, climate change may affect parks and protected areas in many ways:
• Many protected areas were established to protect representative features, ecosystems and
species. As ecosystems move and change in response to climate change, some may be lost
from the fixed boundaries of protected areas.
• The selection and design of future protected areas may need to be adjusted to better allow
species and ecosystems to migrate in response to climate change.
• Patterns of recreational use may also change. Summer activities such as camping and swimming
may be affected. Spring and fall recreational use may become more popular. As the winter
season shortens and snow cover becomes less reliable, opportunities for winter activities may decline.
• Protected areas will be subject to the changes that affect other natural areas. These may
include more natural disturbances such as forest fires, insect outbreaks, storms, and floods; lower
water levels, especially along the Great Lakes; more invasive species, both in the water and on land;
and less habitat for fish that require colder water.
The following report provides more information about the effects of climate change on some of Ontario’s protected areas:
• Climate Change and Ontario's Provincial Parks: Towards an Adaptation Strategy CCRR-06
PDF 2.3 Mb
Far North
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| Polar Bear Provincial Park |
The Far North is a vast, largely undeveloped and important part of our province. The forests, peatlands and wetlands that make up the Far North absorb more than 12 million tonnes of carbon dioxide from the air each year and store the equivalent of 97 billion tonnes of carbon dioxide.
The Far North provides essential habitat for more than 200 sensitive species, including species at risk like woodland caribou and wolverine, and Ontario’s only populations of polar bears, beluga whales and snow geese.
Ontario’s Far North may be impacted by climate change in several ways:
• Changes in temperature and precipitation will be the greatest in the northern most part of Ontario.
These changes will lead to reductions in soil moisture, lake levels, and river flow.
• Reductions in the extent of ice cover is already affecting polar bear populations in the Hudson
Bay Lowlands, lowering reproductive success, survival rate and abundance.
• Warmer and longer summers combined with warmer and shorter winters may lead to the loss
of permafrost, which will change surface hydrology and local topography. It is expected that
peatlands could shift from acting as a carbon sink to a carbon source as permafrost thaws
and methane is emitted.
• Tree growth and survival in the northern boreal forest zone may be affected due to a range of
impacts, from increases in growth due to a lengthening growing season to temperature induced
drought stress. Black spruce, a dominant northern boreal species, is particularly sensitive to
increased growing season temperatures.
• The duration and extent of forest fires is expected to increase.
Read about the effects of a changing climate on peatlands in permafrost zones in Ontario
To learn more about the known and potential impacts of climate change on the Far North, read the Far North Science Advisory Panel’s “Science for a Changing Far North”.
The Far North of Ontario & Climate Change








