When you look out the window, you expect that the land will look different depending on the time of year. Snow comes and goes. Plants grow and die. Fall colours flare and then fade. These are the natural seasonal changes we all notice.

However, if you live in places like Resolute Bay, Nunavut or Paulatuk, NWT, you don’t expect to open your curtains one morning and see a forest instead of the arctic tundra! But forests are slowly expanding north thanks to climate change. The shape of the land is also changing and shifting.

These changes are happening slowly and you might not notice them from day to day. Still, the land around us is changing! This backgrounder takes you on a tour of some of these changes.

Disappearing Act: Permafrost

Permafrost is a layer of permanently frozen ground that is under nearly half of Canada! It exists wherever ground temperatures remain below 0ºC (on average) throughout the year. When it is above freezing the top layer – called the “active” layer – may melt. But it will freeze again in the colder temperatures.

By 2080, winter temperatures over the land areas in the Arctic could rise 2.5º to 14ºC above current normal temperatures. Summer temperatures are expected to increase by 4ºto 7.5ºC above what we now usually get. So there’s going to be a whole lot of melting of permafrost going on!

When ice-rich sections of frozen ground melt, underground cavities are created. Unfortunately, there isn’t a permafrost dentist that can come and fill these cavities. So, as the ice melts and the water flows away, the ground above sinks and slumps into the cavities. Trees can topple and ponds can be created in these new low areas. This can have an impact on wildlife that live in the neighbourhood.

For example, in some areas near Fairbanks, Alaska, the permafrost has melted underneath forested areas. The trees have toppled and new low areas have filled with water. So now, instead of forests, these areas are mostly grasslands and wetlands. This change has attracted moose and ducks which like the new habitat, but the woodland caribou have moved away to forested areas because that is what they prefer. This means local people have had to change their hunting practices as the species around them have changed.

People in the north have also seen more landslides because of melting permafrost. Like warmed icing on the side of a cake, the wet, melted slopes slide downwards. Sometimes melted riverbanks give way and fall into the water. This causes more dirt – more sediment – to go into streams and rivers. Increased sediment in the water can harm some types of fish as it makes it harder for them to breathe. Increased sediment can also bury spawning sites.

Permafrost

Withering Wetlands?

“Models predict that land areas in the Arctic will receive substantially increased snowfall in winter and that the climate will be markedly warmer. Summer could be much warmer and wetter than present… [S]mall rises in temperature will result in increased melting of snow and ice, with consequent impacts on the water cycle…. There will be more ponding of water in some areas, but peatlands may dry out because of increased evaporation and transpiration from plants.”

Climate Change 2001: Impacts, Adaptation and Vulnerability, Intergovernmental Panel on Climate Change

On the one hand, melting permafrost can create new wetlands (like the ones near Fairbanks) because new low areas are created that will fill with water. And some climate models project that the Arctic will get more rain and snow than it used to.

On the other hand, warmer temperatures caused by climate change could also mean some wetlands will dry up. This is because more water will evaporate as temperatures rise. In addition, if permafrost under the wetlands melts, water can quickly drain away. If the water level in some wetlands drops, the plants and wildlife that currently thrive in these wetland areas could have a hard time surviving.

Bison Feeding

Right now, wetlands cover about 14% of Canada. Most of these wetlands are found in the Prairies and southern NWT but there are also important ones in the northern Yukon. All of Canada’s wetlands provide important homes to rare or threatened species. Huge numbers of birds hang out in the wetlands in the summers, having their babies and fattening up for winter.

A few years ago, the Gwitch’in people from Old Crow argued that the wetlands in their area were drying up. So government scientists looked at satellite images of these internationally significant wetlands taken in 1973 and 1999. The satellite images confirmed what the Gwitch’in were saying – the wetlands in the Old Crow Flats had lost about 6.8% of their surface area in the 26-year period.

Plants and Trees on the Move

When plants and trees start to move into new places, it is not like you can sit and watch them travel by your door. But trees might not be as slow as you think!

Do you currently spend time near the edge of the boreal forest? Some computer models predict that an expected increased temperature of just 0.2ºC per decade could create growing conditions that would allow the boreal forest to move northward an average of 30 kilometres every ten years! If these computer models happen to be right, by the time you are ten years older, you should notice that the edge of the forest has moved further north!

However, other computer models look at more than just temperature and moisture levels when they try to predict what our forests will look like in the future. These other models also look at things like soil conditions and how plant and animal species migrate. These models say we can’t really be sure how fast the forests will move north. But it is safe to say that the most of the species in the forests will move northward. How fast and how far they will move is up in the air.

A forest is more than trees!

It’s important to remember that a forest is more than plants and trees. For example, a healthy forest needs little microbes – bacteria and fungi – to live in the soil because these microbes help turn dead plants into nutrients in the soil. These nutrients help the live plants and trees grow.

Some people think that the microbes in the soil will not be able to travel northwards quite as fast as the trees and shrubs. So, although the warmer weather will help new plants and trees survive farther and farther north, they need their microbe buddies to come along if they are going to make a healthy forest.

The boreal forest is also made up of many different tree and plant species. The seeds of some of these species are spread by the wind. The seeds of other plants and trees are spread by birds and animals. So even if the temperature and moisture levels improve over time in the north, the rate of spread of the different seeds will influence how far and fast the forest moves north.

The amount of water, the amount of nutrients in the soil, the frequency of fire and the number of insect outbreaks are also things that could affect how fast forests move northwards.

In other words, plants and trees will need more than just warmer weather before they can speed north. A forest is a connected network and all the parts in the network need to be able to make the trip. This is why some scientists don’t think the forests will move very quickly towards the North Pole.

As forest ecosystems move north, this means they will take up space that tundra ecosystems now occupy. This will affect the plants and animals that call the tundra home. Tundra plants and animals may get squeezed out by new forests and have to move even farther north.

The vegetation in northern Canada is already changing in some areas. Shrubs and vegetation that need more moisture have been seen farther north as the north has been getting more rain and snow. Willows are one example of a shrub that has been observed farther north than usual. Moose do well where willows and other shrubs grow so they are benefiting from this increase in shrubs. Berries have also been reported to be more plentiful after wetter weather, which is good news for the animals – including humans – that eat them!

However, mosses and lichens, important foods for caribou, are declining as the climate changes and as other species move into their space! This is bad news for the caribou and, therefore, for people and other animals that eat caribou!

Plants and trees react mostly to two things – temperature and moisture. A banana tree can’t survive outdoors in the north, as the temperature is too cold. A lodgepole pine tree can’t survive near the equator, as the temperature is too hot! And plants that can live in a desert, can’t survive in a wet coastal area.

In other words, every plant and tree needs a certain temperature range and amount of water to survive. As climate change is all about changes in temperatures and amounts of precipitation, it is bound to have an impact on our plants and trees.

If the temperature and moisture levels change quickly, plants have two options for survival: adapt or move. However, a plant can’t just pull up its roots and move to a place with better conditions. If a species of plant or tree can’t adapt quickly enough to changes in the climate, or migrate fast enough to a more suitable area, then it may die out. Competition for space from other, newer species can also cause problems for native plant or tree species.

Have you noticed any changes in the plants and trees in your area? Have you heard others tell stories of new plants or shrubs?

Too hot for comfort

The forests in the north are called boreal forests. They are made up mostly of spruce, pine and aspen trees. The boreal forests are drier than the temperate or coastal forests you would find in wetter regions in Canada.

Right now, forest fires in the boreal forests of Canada burn an average of 2.5 million hectares every year. Fire is a natural part of the life cycle in a boreal forest. It helps shape the landscape and provides a rich patchwork of young and old forests, each with different types of vegetation.

However, as climate change will result in warmer temperatures, forests will likely be drier than usual. With drier forests, we can expect to get bigger and more frequent forest fires.

Larger and more frequent fires will have a number of impacts. For one, if forests burn more frequently, it will mean that forests don’t get a chance to get as old as they used to. This will impact birds and animals that are suited to living in old, mature forests because there will be fewer old forests around. For example, some birds only nest in holes in old, dead trees. They won’t be able to find a place to nest in a young forest!

More fires will also cost more money to fight and threaten more communities.

More forest fires will also release more carbon dioxide (a greenhouse gas that causes climate change) into the atmosphere. Even though trees breathe in a lot of carbon dioxide when they are alive (through a process called photosynthesis), when they burn they release a lot of the carbon they absorbed (see Backgrounder 3).

The Intergovernmental Panel on Climate Change estimates that two-thirds of the world’s boreal forests could disappear – from fires and insect damage – if we continue to put lots of greenhouse gases in the atmosphere.

So What Else is Happening in the North?

As the land changes, and the plants and trees come and go, the animals that live on the land will be affected. To get a better idea of what northern wildlife might be facing with climate change, read Backgrounder 8. Check out backgrounder 7 for information on how the northern world of ice and water is being affected by climate change.

Key Points

As the climate warms up, a lot of the permafrost that is in the ground in the north will melt. This will cause trees to topple and new wetlands to be created.
Although the north is expected to get more rain and snow as the climate changes, some wetlands will dry up or get smaller as warmer temperatures will cause more water to evaporate, or permafrost under them to melt so they drain.
Plants, shrubs and trees will move northwards as the temperatures warm up and moisture levels change. However, the speed of movement will depend on a number of factors.
As forests move northwards, they will replace the tundra environment. This will affect plants and animals that now live on the tundra.
There will be larger and more frequent forest fires as the climate warms up.

Want to Know More?

Check out these sites to find out more about the impacts of climate change in the north and the rest of Canada:

Arctic Borderlands Ecological Knowledge Co-op: http://www.taiga.net/coop/projects/plantcol.html – Do it yourself project! Start a community plant collection.
Climate Change in Canada Poster Site: http://adaptation.nrcan.gc.ca/posters/ – Click on regional names under the Canadian map to bring up lots of information about climate change specific to Nunavut and Western Arctic (Yukon and NWT).
Climate Impacts Map: http://www.climatehotmap.org/ – Click on the map in your region, and you’ll link into a description of climate change indicators in that area.
Community Adaptation and Sustainable Livelihoods: http://www.iisd.org/casl/projects/inuitobs.htm – Don’t miss the video, Sila Alangotok: Inuit Observations on Climate Change. You can view a short version at this site, or get information on buying it.
Government of Canada Climate Change (Regional Impacts): http://www.climatechange.gc.ca/english/affect/prov_territory/ – Click on northern sections of the map to see what the impacts are in NWT, Yukon and Nunavut.
NASA Earth Observatory: http://earthobservatory.nasa.gov/Study/BorealMigration/boreal_migration4.html – All about boreal forest migration.
Plantwatch Canada: http://www.devonian.ualberta.ca/pwatch – A plant-watching project for classes.
UNEP (Report on impacts in the Polar regions): http://www.grida.no/climate/ipcc_tar/wg2/592.htm – An amazing collection of scientific information on climate change imparts in the Arctic and Antarctic.