012113/012813 The Physical Geography of the Canadian Arctic
GEO605 Geography of the Canadian North
012113/012813 The Physical Geography of the Canadian Arctic ARCTIC CLIMATE • The basis of the north is its climate • Land of the midnight sun o The sun shines at midnight during the summer above the Arctic Circle In the summer, the sun never sets; in the winter, the sun never rises Positions of the sun and the earth: summer solstice, autumnal equinox, winter solstice, vernal equinox As you move away from the equator, you get the concept of longer days/longer nights o 66.5 degrees N latitude o At 70 degrees N, the sun sets in November and doesn't come back until mid January • Extremely cold temperatures o A lot less solar radiation (even with 24 hours of sunlight in the summer) When the sun shines, we get the same amount of energy but due to the tilt of the earth, solar energy has to cover twice the amount of land for the same amount of energy Even with long sun days, there is not enough energy to cover the land o 2 months of the year (July and August have average daily temperatures above freezing (0°C) o In Toronto, 2.5 months are below freezing (0°C) o In Orangeville, 2 months are below freezing (0°C) • Very little precipitation o Less than 200mm (Toronto gets about 900mm) o Most of which is snow in a frozen state for most of the year • Very windy o Warm air rises off of the land and cold air (cold front) fills the void ELECTROMAGNETIC (EM) RADIATION • Electromagnetic radiation varies with wavelength/frequency producing different properties of energy – the Electromagnetic Spectrum o Earth absorbs solar radiation and slows down the energy and becomes infrared heat (thermal radiation) o Our atmosphere is made of chemicals which absorbs different portion in the spectrum If black, has 100% absorption o Atmospheric window (white) which allows visible light to pass through ATMOSPHERIC STRUCTURE • Layers (from surface) due to: o Density (pressure) Different portions of the spectrum goes through the atmosphere o Radiation environment Atmosphere acts as a blanket that keeps the heat in The more greenhouse gasses we add into the atmosphere, the more heat we keep in the atmosphere o Temperature ABSORPTION OF TERRESTRIAL RADIATION • Water vapor: is an excellent absorber of terrestrial radiation in wavelengths of less than 7um • Carbon dioxide: is an excellent absorber of terrestrial radiation in wavelengths longer than 12 um o
Level has been increasing because of burning fossil fuel
GEO605 Geography of the Canadian North Concentration in the atmosphere is rising Annual cycle increases in May and June, but decreases in the fall Plants that grow take in carbon dioxide in the photosynthesis process; in the fall, the plants release the carbon dioxide which further increases carbon dioxide concentration in the atmosphere o As of January 2013, current carbon dioxide level is 393.55ppm Methane: is an excellent absorber of terrestrial radiation in wavelengths of near 7um o
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Human activities have changed the composition of the atmosphere since the pre-industrial ear o Carbon dioxide, nitrous oxide, methane, and sulfur are the four components that makes the atmosphere thicker
GREENHOUSE EFFECT • Greenhouse effect: the absorption of terrestrial radiation by the gases in the Earth's atmosphere o Solar radiation easily passes through the glass in the greenhouse o Solar radiation is absorbed and stored as internal energy inside greenhouse increasing the temperature Temperature in the glass house stays warm o Terrestrial radiation is by the glass and the energy stays inside the greenhouse o The walls and sides of the greenhouse keep the cooler outside air from missing with the warmer air inside the greenhouses • Roughly half of the solar radiation passes through the atmosphere and is absorbed by the Earth's surface • Approximately 86% of the terrestrial radiation emitted by the surface is absorbed by gases in the atmosphere and only 14% escapes to space o Energy balance is the measurement of energy going into the earth and the amount of energy that comes back out •
The Earth's greenhouse effect occurs when terrestrial radiation emitted by the surface is absorbed in the atmosphere and then is radiated back to the surface as terrestrial radiation emitted by the atmosphere o Income solar radiation from space causes terrestrial radiation reaching space o The terrestrial radiation is absorbed by the atmosphere and some terrestrial radiation emitted by the atmosphere back to the surface of the Earth
ATMOSPHERIC STRUCTURE • Increasing CO2, Methane • Increases density of the atmosphere • More GHG is absorb Thermal Infrared Radiation WHAT IS CLIMATE CHANGE? • Climate change not necessarily Global Warming o The poles are where we see majority of the changes; temperature at the equator stays relatively the same Global warming is an AVERAGE measurement (some areas have warmer days and others have cooler days) o Climate has always changed; it is not equally balanced in the globe o The Arctic has been much warmer and cooler in the past • Huge increase in Anthropogenic Carbon Emissions since the Industrial Revolution • Atmospheric carbon changes our atmospheric windows o Long wave radiation (heat) cannot escape • Some feel that the changes we are seeing are natural fluctuations
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GEO605 Geography of the Canadian North Solar cycles and micro-orbital shifts That is not enough though to account for the rate of change Ozone absorbs more ultraviolet
HOW DO WE KNOW THE CLIMATE IS CHANGING? • Direct measurements o Temperature measurements Temperature trend is continuously increasing • Proxy measurements o Estimations of past climates based on indirect evidence Paleo-climatoloty: study if indirect evidence of climate change In glaciers, there are pockets of frozen air that can be used to measure the temperature o Ice cores Trap gases and show past concentrations Date the age of the ice based on isotopes o Sediment cores Varves (layers of soil/mud) measured based on sediment thickness/depth Carbon dating Diatoms are plankton and other microorganisms in the water • Each band of dark and light represents layers of years to tell the difference based on the skeleton remains • Increase in certain species that didn’t exist in the past because temperature in the water is becoming warmer CONSEQUENCES OF CLIMATE CHANGE • Land surface o Permafrost degradation o Vegetation shifts • Wildlife o Change in habitat • Sea ice o Reduction in cover and changes to patterns o Reduced Albedo • People o Change in lifestyle WHAT IS TUNDRA? • Tundra is from the Finnish word "Tunturia" (treeless plain) • Alpine (high in latitude) and arctic tundra (high in elevation) • Both are defined by the extent of the treeline o Treeline is the boundary where for climatic reasons tree's can no longer grow normally • Youngest Biome is only 10,000 years old •
Tundra is characterized by: o Extremely cold climate o Limitation on drainage o Short season of growth and reproduction o Low biotic diversity o Simple vegetation structure o Energy and nutrients in the form of dead organic material
GEO605 Geography of the Canadian North o
Large population oscillations
PERMAFROST • Permanently frozen ground o The Arctic takes more carbon than they use to because some plant materials trapped and thaws out carbon dioxide • Continuous (everywhere) or discontinuous (patchy) • Treeline also defines the continuous permafrost line o Tree roots cannot grow in continuous area where roots do not grow deep • Active layer thaws in the summer • Depth of the active layer depends on many things o Vegetation o Summer temperature o Soil type PERIGLACIAL ENVIRONMENT • Describes a suite of processes dominated by freezing and ice formation and the landforms that are created and affected by these processes (created near glaciers) • Key is repeated freeze thaw cycles LANDSCAPE SHAPED BY ICE AND FROST • Ice wedge polygons o Cracks are formed because it is too cold o In the spring, the crack is filled with water and then freezes again in the winter o Expands and contracts the soil to create different shapes o Vegetation only in the cracks because of moisture and more nutrients in the loosened soil • Flat ground • Gentle slope • Sloped surface • • •
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Frost shattering o When water freezes it expands 10% o Water seeps into cracks, joints, and bedding planes in rock, freezes, and splits the rock Frost heave o Soilfluction lobe where soil is flowing downhill because it is freezing and thawing o When the ground freezes, it expands Monument stones o More vegetation around the rock because more nutrients from animals in the life cycle (sudden changes in landscape have big effects) o For example, owls hunt and carry food to monumental rocks for feeding and dropping owl pellets around the monument Mud boils o Two possible causes: more moisture and take longer to freeze which pushes mud to the top OR permafrost melts Snow and snow melt o The perception that falls happen in the winter o Melt water from the snow gets redistributed is what “kicks off the system” o When melted, it is rapid, where stream channel flows on top of the land o Snow accumulates in a valley is where the river was flowing in the earlier season Erosion o Because of more perception and permafrost melt
o
GEO605 Geography of the Canadian North Stream is undercutting the bank (cave like) where stream undercuts permafrost which begins to slump off because soil and vegetation is held up by ice
DRASTIC LANDSCAPE CHANGES • Changing weather (including major rain event) with mix of conditions: permafrost melting affecting the soil and precipitation adding moisture • Removes vegetation from movements RIVER AND SEDIMENT MONITORING • Monitor and measure amount of river flow to measure amount of sediment in the system and the water RAISED BEACHES • Concentric rings along the Arctic Ocean which is a ridge to a lower level • Each ridge line was part of the beach o Sea level has not gone down; land has moved upward o Land was glaciated which presses the land down o When weight is removed the land moves back up; referred to as isostatic rebound • Land is rebounding at the same rate in the arctic • Evidence of arctic people with camp sites with age and estimation of the historic date PINGO'S • Hills form on tundra because of permafrost (around Mackenzie Delta) • Wet land area with a hill that is dryer and the higher up is winder o Less insects but attracts other wildlife because of elevation that reduces chances of flooding • Inside the Pingo is an ice core ESKERS • Landform on landscape that changes from elevation • Caused by glacier; when melting created river bringing along sand and gravel which gets deposited along the ground o It is old rivers within the ice o Water inside melts and the sand and soil settle down to create the land elevations • Importance is the elevation running along several kilometers o Becomes traveling ground for wildlife and hunting ground because if dryer area o Aboriginal camps are set up on the ridges o Important ecologically and culturally o Helped with the discovery of diamonds • Important to industry with the discovery of diamonds NUTRIENT CYCLES • Because of industrial, level of carbon dioxide is increasing VEGETATION • Very short growing season - June to mid August o Nutrients important to cycle o Water provided by snow melt o Vegetation is rarely moisture limited o Plants are able to utilize solar energy when it is available • Plants have various adoptions for the arctic o Short stature - low lying Warmth and wind protection
GEO605 Geography of the Canadian North Adapted photosynthesis for cool temperatures Use more of the sun energy The closer you are to the ground, the warmer it is o They don't seed every year - save energy Not a lot of annual plants Takes a lot of energy, so plants adapt to environment to preserve seeds The biggest limitation to plant growth is nitrogen o Common fertilizer for lawn o Nitrogen is a limiting factor in the north because o 70% of atmosphere is nitrogen o Nitrogen gas is not useable to plants o
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Perennial snow bank is there all year round but decreasing in size Provides moisture all year round
VEGETATION COMMUNITIES • Wet sedge (boggy, mossy and pete is thick) • Nostic (nitrogen fixing cyno-bacteria) o Takes nitrogen and turns it into a usable form • Polar desert o Early summer is wet and muddy which means there is moisture but not the same level of nitrogen • Prostate dwarf shrub o Arctic willow tree • Graminoid (grasses) forb (flowering) o In mesic type of environment (not too wet, not too dry) o Lower nitrogen level, less vegetation • Frost shattered rock o Vegetation growing on rocks (moss) PLANTS • Purple saxifrage – able to photosynthesized even when snow or frost is covering it • Arctic poppy – territorial flower for NWT o Flower is generally points towards the sun (even as the sun rotates) o Stem of the plant has an enzyme that allows for growth o Differentiation in growth cause stem to turn • Wooly lousewort – the plant has a furry cover, which traps heat in to enhances its ability to photosynthesize • Mountain sorrel – not limited to the arctic o Goes red in the fall and has a lot of vitamin C o Tastes like rubar (?) • Spider saxifrage 1. Able to have sexual and asexual production 2. Its tentacles when it reaches the soil, it can produce a new plant ARCTIC ANIMALS • All of the arctic wildlife have adaption specific to the arctic climate • Main species groups 1. Birds Over 100 different species of birds in the arctic Only 11 are permanent residents
GEO605 Geography of the Canadian North 90 species migrate to the arctic to breed (some migrate as far as South America in the winter) Majority are waterfowl (ducks, geese, loons, gulls) • Less predators in the north for these birds, they migrate north to have a better chance to survival All of the species are there to breed They all have a very short window to: mate, hatch young, feed them, keep them safe, get them ready for winter
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Resident birds • Only 11 species: 6 are land birds • 3 meat eaters: falcons, ravens, and snowy owl • 3 vegetarians: 2 types of ptarmigans and redpoll (small Finch type bird)
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Snowy owl is the largest of the owls • 1/2 metro high with 1.5m wing span • They'll sit on high patches of snow in spring • In the summer they sit on rocks to look for mice • Needs to eat 7-12 mice a day and is active day and night because of all day sun
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Owl perch • Random lush and green land • Owls will sit on the perch and digest the mice, regurgitate owl pellets • Owl pellets change the dynamic of the nutrients on the land
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Ptarmigan is the member of the grouse family • Not very smart and is very well camouflaged • Speckled brown in summer • White in the winter • Very protective of its young • Baby ptarmigan picture
2. Arctic mammals (land and sea) Well developed food chain in the arctic Solar energy is transformed into biomass Herbivores (vols, lemmings, caribou, muskox) consume biomass Carnivores (arctic fox, wolves, polar and grizzly bear) consume herbivores
Both have to find ways to deal with cold long winters and find food Consequences to the wildlife • Changes to the climate impact vegetation • Changes work their way up the food chains • Habitat ranges of some species will increase while other decrease, tundra decreases as temperature increases • Ranges will start to overlap
Malthusian growth (time vs population size) • Carrying capacity of the environment • Overshoot (too many species); dieback (they die out) • E.g. caribou species
GEO605 Geography of the Canadian North 3. Herbivores Plentiful in the north – rodents Population die backs of rodents, effects carnivore populations Main food supply for owls, foxes, and wolves SikSik's (ground squirrels) Barren Land Caribou live on the mainland • They migrate, they move in the wintertime to the treeline Peary Caribou - smaller and live on the arctic islands • Reindeer are domesticated caribou Muskox • Remnant species from the last ice age. Skulls weigh 50 lbs. 4. Carnivores Arctic wolves • Primarily eat rodents (Caribou and Muskox if they can) Grizzly bears • Live on the mainland, Arctic Ocean to the territories • Eat primarily rodents, berries Polar bear • Spends its winter on the sea ice; late summers they will move inland • Main food source is seal • Map of polar bear ranges • Female polar bears breed on the sea ice, raise their young to 1yr old. Arctic fox • Fox goes out onto the sea ice; it will follow the polar bear to the sea ice • In the summer they lose the white fur, and hunt for rodents 5. Insects 6. Fish SEA ICE • Salt gets pushed out of multi-year ice. Becomes fresh water • Sea ice is found in Polar Regions • Sea ice covers approximately 25 million square kilometers of the earth (about 2.5 times the size of Canada) • Sea ice is made from frozen ocean water o As the ocean freezes, the salt collects in droplets called brine o Brine is eventually squeezes out - multi-year ice is fresh enough that melted, people can drink it • • •
Keeps the Polar Regions cool and the globe cool o Cold water sinks down, warm water rises o Sea ice reflects 80% of the sunlight; open sea water absorbs 90% of sunlight Helps to regulate climate o It moderates ocean temperatures, which play a role in air temperature It provides life support for people who live in the Arctic and for animals that live above and below the ice o Sea ice is an important hunting ground for people and animals o Provides shelter, birthing, and resting areas for animals
CHANGES TO SEA ICE • Positive feedback for temperature and precipitation o Reduction in Albedo (reflection of solar energy) • Less sea ice we have, the less sea ice we have for the next year
GEO605 Geography of the Canadian North •
September is the minimum amount of sea ice in the year
SCIENCE IS WRONG CONSEQUENCES OF A REDUCTION IN SEA ICE • Environmental o Reduction in habitat o Increase in ocean temperature • Socio/economical (Inuit) o Flow edge is important hunting ground for Inuit o Species changes (polar bear, seal, fish) o Most Inuit sustain themselves with Country Food • Northwest passage – Canadian sovereignty SEA ICE IMPACTS ON MAMMALS • A lack of sea ice or poor conditions cause stress for marine mammals and affect their abilities to reproduce o Arctic fox Can get stranded and migration routes become inaccessible; as a result, hunting areas change Foxes follow polar bears but bears can swim to food When ice breaks down under the fox, they will drown Consume resources on ice and for migrating from land to land • They will be stranded if the ice breaks before or during the travels o Caribou Migration routes became inaccessible Foraging becomes more difficult Can fall through very thin ice during migration • Expected reductions in sea ice will shrink marine habitats and may push some species to extinction SEA ICE IMPACT ON SEALS • Many seals (harp, hooded, ringed, bearded, spotted, and ribbon seals) live in the Arctic along the sea ice edge • Ice is used for resting and birthing o There is a small land, increases dependence on resources on that small land • Some seals use the snow on the ice to create dens • Seal mothers leave their pups on the ice while they hunt nearby SEA ICE IMPACT ON POLAR BEARS • Polar bears use multi-year ice as a platform for hunting seals o They must eat a lot during the winter in order to survive summers on land o Solid platform for travels from seal ground to seal ground o Seal is main food source Rely on fat storage in the summer Loss of sea ice impact polar bear habitat in the southern north Decrease in species number • The bears also build their dens on the ice SEA ICE IMPACT ON PEOPLE • Small changes can have drastic consequences for people who subsist off the land o People rely on the sea ice for transportation, hunting, and shore protection o People must now change their hunting strategies and face more dangerous situations
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GEO605 Geography of the Canadian North Different from Aboriginal because of length of time and contact with Europeans and the rest of Canada o Lifestyle and impact on Canada about 60-70 years Challenges with climate change and impact of the Inuit o Hunting for food on the sea; imported food are more expensive o Eliminating food source
IMPACTS ON HUNTING • Loss of sea ice means the animals are farther away o Traveling a greater distance is both dangerous and expensive • Loss of sea ice can lead to o Accidents on thin ice o More severe storms o Inadequate storage NORTHWEST PASSAGE • As of 2008, the NWP southern route has been navigable for a record 3 consecutive years o Northern deep draft channel had been navigable throughout its length for the first 2 years in recorded history • Bathurst Inlet Port and Road o Ice roads are melting faster and freezing later o Base metals cannot be flown out like diamonds and gold o No deep water port on our Arctic Coast Arctic Bay announced 2007 o Sovereignty •
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Political concern (connects through two international bodies of water) o Canada considers it internal Canadian waters No navigation of the passages because we do not know which parts are shallow or deep due to years of ice Canadian government is not willing to spend money to navigate it Should be concerned because of the amount of resources in the north Economical concern (no navigation increases risk of accidents of boats traveling through the north) o We do not have the capacity to contain environmental damages from ship wrecks from oils and gasoline in the cold weather Cannot get base metals out because no roads or railways o Izok has large deposit of lead and zinc Important for steel development Now owned by a Chinese development company Plan to build a road that connects to Bathurst Inlet where a port is planned to be built on the southern part What we miss is the quality of sea ice We lose out on multi-year ice Ice is rotating counter clockwise Older ice is being flushed out of the arctic Ice is not thick enough and it melts a lot quicker As ice melts, solar radiation reelects into the water, warming it up, causing the ice to melt more
012113/012813 The Physical Geography of the Canadian Arctic ARCTIC CLIMATE • The basis of the north is its climate • Land of the midnight sun o The sun shines at midnight during the summer above the Arctic Circle In the summer, the sun never sets; in the winter, the sun never rises Positions of the sun and the earth: summer solstice, autumnal equinox, winter solstice, vernal equinox As you move away from the equator, you get the concept of longer days/longer nights o 66.5 degrees N latitude o At 70 degrees N, the sun sets in November and doesn't come back until mid January • Extremely cold temperatures o A lot less solar radiation (even with 24 hours of sunlight in the summer) When the sun shines, we get the same amount of energy but due to the tilt of the earth, solar energy has to cover twice the amount of land for the same amount of energy Even with long sun days, there is not enough energy to cover the land o 2 months of the year (July and August have average daily temperatures above freezing (0°C) o In Toronto, 2.5 months are below freezing (0°C) o In Orangeville, 2 months are below freezing (0°C) • Very little precipitation o Less than 200mm (Toronto gets about 900mm) o Most of which is snow in a frozen state for most of the year • Very windy o Warm air rises off of the land and cold air (cold front) fills the void ELECTROMAGNETIC (EM) RADIATION • Electromagnetic radiation varies with wavelength/frequency producing different properties of energy – the Electromagnetic Spectrum o Earth absorbs solar radiation and slows down the energy and becomes infrared heat (thermal radiation) o Our atmosphere is made of chemicals which absorbs different portion in the spectrum If black, has 100% absorption o Atmospheric window (white) which allows visible light to pass through ATMOSPHERIC STRUCTURE • Layers (from surface) due to: o Density (pressure) Different portions of the spectrum goes through the atmosphere o Radiation environment Atmosphere acts as a blanket that keeps the heat in The more greenhouse gasses we add into the atmosphere, the more heat we keep in the atmosphere o Temperature ABSORPTION OF TERRESTRIAL RADIATION • Water vapor: is an excellent absorber of terrestrial radiation in wavelengths of less than 7um • Carbon dioxide: is an excellent absorber of terrestrial radiation in wavelengths longer than 12 um o
Level has been increasing because of burning fossil fuel
GEO605 Geography of the Canadian North Concentration in the atmosphere is rising Annual cycle increases in May and June, but decreases in the fall Plants that grow take in carbon dioxide in the photosynthesis process; in the fall, the plants release the carbon dioxide which further increases carbon dioxide concentration in the atmosphere o As of January 2013, current carbon dioxide level is 393.55ppm Methane: is an excellent absorber of terrestrial radiation in wavelengths of near 7um o
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Human activities have changed the composition of the atmosphere since the pre-industrial ear o Carbon dioxide, nitrous oxide, methane, and sulfur are the four components that makes the atmosphere thicker
GREENHOUSE EFFECT • Greenhouse effect: the absorption of terrestrial radiation by the gases in the Earth's atmosphere o Solar radiation easily passes through the glass in the greenhouse o Solar radiation is absorbed and stored as internal energy inside greenhouse increasing the temperature Temperature in the glass house stays warm o Terrestrial radiation is by the glass and the energy stays inside the greenhouse o The walls and sides of the greenhouse keep the cooler outside air from missing with the warmer air inside the greenhouses • Roughly half of the solar radiation passes through the atmosphere and is absorbed by the Earth's surface • Approximately 86% of the terrestrial radiation emitted by the surface is absorbed by gases in the atmosphere and only 14% escapes to space o Energy balance is the measurement of energy going into the earth and the amount of energy that comes back out •
The Earth's greenhouse effect occurs when terrestrial radiation emitted by the surface is absorbed in the atmosphere and then is radiated back to the surface as terrestrial radiation emitted by the atmosphere o Income solar radiation from space causes terrestrial radiation reaching space o The terrestrial radiation is absorbed by the atmosphere and some terrestrial radiation emitted by the atmosphere back to the surface of the Earth
ATMOSPHERIC STRUCTURE • Increasing CO2, Methane • Increases density of the atmosphere • More GHG is absorb Thermal Infrared Radiation WHAT IS CLIMATE CHANGE? • Climate change not necessarily Global Warming o The poles are where we see majority of the changes; temperature at the equator stays relatively the same Global warming is an AVERAGE measurement (some areas have warmer days and others have cooler days) o Climate has always changed; it is not equally balanced in the globe o The Arctic has been much warmer and cooler in the past • Huge increase in Anthropogenic Carbon Emissions since the Industrial Revolution • Atmospheric carbon changes our atmospheric windows o Long wave radiation (heat) cannot escape • Some feel that the changes we are seeing are natural fluctuations
o o o
GEO605 Geography of the Canadian North Solar cycles and micro-orbital shifts That is not enough though to account for the rate of change Ozone absorbs more ultraviolet
HOW DO WE KNOW THE CLIMATE IS CHANGING? • Direct measurements o Temperature measurements Temperature trend is continuously increasing • Proxy measurements o Estimations of past climates based on indirect evidence Paleo-climatoloty: study if indirect evidence of climate change In glaciers, there are pockets of frozen air that can be used to measure the temperature o Ice cores Trap gases and show past concentrations Date the age of the ice based on isotopes o Sediment cores Varves (layers of soil/mud) measured based on sediment thickness/depth Carbon dating Diatoms are plankton and other microorganisms in the water • Each band of dark and light represents layers of years to tell the difference based on the skeleton remains • Increase in certain species that didn’t exist in the past because temperature in the water is becoming warmer CONSEQUENCES OF CLIMATE CHANGE • Land surface o Permafrost degradation o Vegetation shifts • Wildlife o Change in habitat • Sea ice o Reduction in cover and changes to patterns o Reduced Albedo • People o Change in lifestyle WHAT IS TUNDRA? • Tundra is from the Finnish word "Tunturia" (treeless plain) • Alpine (high in latitude) and arctic tundra (high in elevation) • Both are defined by the extent of the treeline o Treeline is the boundary where for climatic reasons tree's can no longer grow normally • Youngest Biome is only 10,000 years old •
Tundra is characterized by: o Extremely cold climate o Limitation on drainage o Short season of growth and reproduction o Low biotic diversity o Simple vegetation structure o Energy and nutrients in the form of dead organic material
GEO605 Geography of the Canadian North o
Large population oscillations
PERMAFROST • Permanently frozen ground o The Arctic takes more carbon than they use to because some plant materials trapped and thaws out carbon dioxide • Continuous (everywhere) or discontinuous (patchy) • Treeline also defines the continuous permafrost line o Tree roots cannot grow in continuous area where roots do not grow deep • Active layer thaws in the summer • Depth of the active layer depends on many things o Vegetation o Summer temperature o Soil type PERIGLACIAL ENVIRONMENT • Describes a suite of processes dominated by freezing and ice formation and the landforms that are created and affected by these processes (created near glaciers) • Key is repeated freeze thaw cycles LANDSCAPE SHAPED BY ICE AND FROST • Ice wedge polygons o Cracks are formed because it is too cold o In the spring, the crack is filled with water and then freezes again in the winter o Expands and contracts the soil to create different shapes o Vegetation only in the cracks because of moisture and more nutrients in the loosened soil • Flat ground • Gentle slope • Sloped surface • • •
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Frost shattering o When water freezes it expands 10% o Water seeps into cracks, joints, and bedding planes in rock, freezes, and splits the rock Frost heave o Soilfluction lobe where soil is flowing downhill because it is freezing and thawing o When the ground freezes, it expands Monument stones o More vegetation around the rock because more nutrients from animals in the life cycle (sudden changes in landscape have big effects) o For example, owls hunt and carry food to monumental rocks for feeding and dropping owl pellets around the monument Mud boils o Two possible causes: more moisture and take longer to freeze which pushes mud to the top OR permafrost melts Snow and snow melt o The perception that falls happen in the winter o Melt water from the snow gets redistributed is what “kicks off the system” o When melted, it is rapid, where stream channel flows on top of the land o Snow accumulates in a valley is where the river was flowing in the earlier season Erosion o Because of more perception and permafrost melt
o
GEO605 Geography of the Canadian North Stream is undercutting the bank (cave like) where stream undercuts permafrost which begins to slump off because soil and vegetation is held up by ice
DRASTIC LANDSCAPE CHANGES • Changing weather (including major rain event) with mix of conditions: permafrost melting affecting the soil and precipitation adding moisture • Removes vegetation from movements RIVER AND SEDIMENT MONITORING • Monitor and measure amount of river flow to measure amount of sediment in the system and the water RAISED BEACHES • Concentric rings along the Arctic Ocean which is a ridge to a lower level • Each ridge line was part of the beach o Sea level has not gone down; land has moved upward o Land was glaciated which presses the land down o When weight is removed the land moves back up; referred to as isostatic rebound • Land is rebounding at the same rate in the arctic • Evidence of arctic people with camp sites with age and estimation of the historic date PINGO'S • Hills form on tundra because of permafrost (around Mackenzie Delta) • Wet land area with a hill that is dryer and the higher up is winder o Less insects but attracts other wildlife because of elevation that reduces chances of flooding • Inside the Pingo is an ice core ESKERS • Landform on landscape that changes from elevation • Caused by glacier; when melting created river bringing along sand and gravel which gets deposited along the ground o It is old rivers within the ice o Water inside melts and the sand and soil settle down to create the land elevations • Importance is the elevation running along several kilometers o Becomes traveling ground for wildlife and hunting ground because if dryer area o Aboriginal camps are set up on the ridges o Important ecologically and culturally o Helped with the discovery of diamonds • Important to industry with the discovery of diamonds NUTRIENT CYCLES • Because of industrial, level of carbon dioxide is increasing VEGETATION • Very short growing season - June to mid August o Nutrients important to cycle o Water provided by snow melt o Vegetation is rarely moisture limited o Plants are able to utilize solar energy when it is available • Plants have various adoptions for the arctic o Short stature - low lying Warmth and wind protection
GEO605 Geography of the Canadian North Adapted photosynthesis for cool temperatures Use more of the sun energy The closer you are to the ground, the warmer it is o They don't seed every year - save energy Not a lot of annual plants Takes a lot of energy, so plants adapt to environment to preserve seeds The biggest limitation to plant growth is nitrogen o Common fertilizer for lawn o Nitrogen is a limiting factor in the north because o 70% of atmosphere is nitrogen o Nitrogen gas is not useable to plants o
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Perennial snow bank is there all year round but decreasing in size Provides moisture all year round
VEGETATION COMMUNITIES • Wet sedge (boggy, mossy and pete is thick) • Nostic (nitrogen fixing cyno-bacteria) o Takes nitrogen and turns it into a usable form • Polar desert o Early summer is wet and muddy which means there is moisture but not the same level of nitrogen • Prostate dwarf shrub o Arctic willow tree • Graminoid (grasses) forb (flowering) o In mesic type of environment (not too wet, not too dry) o Lower nitrogen level, less vegetation • Frost shattered rock o Vegetation growing on rocks (moss) PLANTS • Purple saxifrage – able to photosynthesized even when snow or frost is covering it • Arctic poppy – territorial flower for NWT o Flower is generally points towards the sun (even as the sun rotates) o Stem of the plant has an enzyme that allows for growth o Differentiation in growth cause stem to turn • Wooly lousewort – the plant has a furry cover, which traps heat in to enhances its ability to photosynthesize • Mountain sorrel – not limited to the arctic o Goes red in the fall and has a lot of vitamin C o Tastes like rubar (?) • Spider saxifrage 1. Able to have sexual and asexual production 2. Its tentacles when it reaches the soil, it can produce a new plant ARCTIC ANIMALS • All of the arctic wildlife have adaption specific to the arctic climate • Main species groups 1. Birds Over 100 different species of birds in the arctic Only 11 are permanent residents
GEO605 Geography of the Canadian North 90 species migrate to the arctic to breed (some migrate as far as South America in the winter) Majority are waterfowl (ducks, geese, loons, gulls) • Less predators in the north for these birds, they migrate north to have a better chance to survival All of the species are there to breed They all have a very short window to: mate, hatch young, feed them, keep them safe, get them ready for winter
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Resident birds • Only 11 species: 6 are land birds • 3 meat eaters: falcons, ravens, and snowy owl • 3 vegetarians: 2 types of ptarmigans and redpoll (small Finch type bird)
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Snowy owl is the largest of the owls • 1/2 metro high with 1.5m wing span • They'll sit on high patches of snow in spring • In the summer they sit on rocks to look for mice • Needs to eat 7-12 mice a day and is active day and night because of all day sun
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Owl perch • Random lush and green land • Owls will sit on the perch and digest the mice, regurgitate owl pellets • Owl pellets change the dynamic of the nutrients on the land
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Ptarmigan is the member of the grouse family • Not very smart and is very well camouflaged • Speckled brown in summer • White in the winter • Very protective of its young • Baby ptarmigan picture
2. Arctic mammals (land and sea) Well developed food chain in the arctic Solar energy is transformed into biomass Herbivores (vols, lemmings, caribou, muskox) consume biomass Carnivores (arctic fox, wolves, polar and grizzly bear) consume herbivores
Both have to find ways to deal with cold long winters and find food Consequences to the wildlife • Changes to the climate impact vegetation • Changes work their way up the food chains • Habitat ranges of some species will increase while other decrease, tundra decreases as temperature increases • Ranges will start to overlap
Malthusian growth (time vs population size) • Carrying capacity of the environment • Overshoot (too many species); dieback (they die out) • E.g. caribou species
GEO605 Geography of the Canadian North 3. Herbivores Plentiful in the north – rodents Population die backs of rodents, effects carnivore populations Main food supply for owls, foxes, and wolves SikSik's (ground squirrels) Barren Land Caribou live on the mainland • They migrate, they move in the wintertime to the treeline Peary Caribou - smaller and live on the arctic islands • Reindeer are domesticated caribou Muskox • Remnant species from the last ice age. Skulls weigh 50 lbs. 4. Carnivores Arctic wolves • Primarily eat rodents (Caribou and Muskox if they can) Grizzly bears • Live on the mainland, Arctic Ocean to the territories • Eat primarily rodents, berries Polar bear • Spends its winter on the sea ice; late summers they will move inland • Main food source is seal • Map of polar bear ranges • Female polar bears breed on the sea ice, raise their young to 1yr old. Arctic fox • Fox goes out onto the sea ice; it will follow the polar bear to the sea ice • In the summer they lose the white fur, and hunt for rodents 5. Insects 6. Fish SEA ICE • Salt gets pushed out of multi-year ice. Becomes fresh water • Sea ice is found in Polar Regions • Sea ice covers approximately 25 million square kilometers of the earth (about 2.5 times the size of Canada) • Sea ice is made from frozen ocean water o As the ocean freezes, the salt collects in droplets called brine o Brine is eventually squeezes out - multi-year ice is fresh enough that melted, people can drink it • • •
Keeps the Polar Regions cool and the globe cool o Cold water sinks down, warm water rises o Sea ice reflects 80% of the sunlight; open sea water absorbs 90% of sunlight Helps to regulate climate o It moderates ocean temperatures, which play a role in air temperature It provides life support for people who live in the Arctic and for animals that live above and below the ice o Sea ice is an important hunting ground for people and animals o Provides shelter, birthing, and resting areas for animals
CHANGES TO SEA ICE • Positive feedback for temperature and precipitation o Reduction in Albedo (reflection of solar energy) • Less sea ice we have, the less sea ice we have for the next year
GEO605 Geography of the Canadian North •
September is the minimum amount of sea ice in the year
SCIENCE IS WRONG CONSEQUENCES OF A REDUCTION IN SEA ICE • Environmental o Reduction in habitat o Increase in ocean temperature • Socio/economical (Inuit) o Flow edge is important hunting ground for Inuit o Species changes (polar bear, seal, fish) o Most Inuit sustain themselves with Country Food • Northwest passage – Canadian sovereignty SEA ICE IMPACTS ON MAMMALS • A lack of sea ice or poor conditions cause stress for marine mammals and affect their abilities to reproduce o Arctic fox Can get stranded and migration routes become inaccessible; as a result, hunting areas change Foxes follow polar bears but bears can swim to food When ice breaks down under the fox, they will drown Consume resources on ice and for migrating from land to land • They will be stranded if the ice breaks before or during the travels o Caribou Migration routes became inaccessible Foraging becomes more difficult Can fall through very thin ice during migration • Expected reductions in sea ice will shrink marine habitats and may push some species to extinction SEA ICE IMPACT ON SEALS • Many seals (harp, hooded, ringed, bearded, spotted, and ribbon seals) live in the Arctic along the sea ice edge • Ice is used for resting and birthing o There is a small land, increases dependence on resources on that small land • Some seals use the snow on the ice to create dens • Seal mothers leave their pups on the ice while they hunt nearby SEA ICE IMPACT ON POLAR BEARS • Polar bears use multi-year ice as a platform for hunting seals o They must eat a lot during the winter in order to survive summers on land o Solid platform for travels from seal ground to seal ground o Seal is main food source Rely on fat storage in the summer Loss of sea ice impact polar bear habitat in the southern north Decrease in species number • The bears also build their dens on the ice SEA ICE IMPACT ON PEOPLE • Small changes can have drastic consequences for people who subsist off the land o People rely on the sea ice for transportation, hunting, and shore protection o People must now change their hunting strategies and face more dangerous situations
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GEO605 Geography of the Canadian North Different from Aboriginal because of length of time and contact with Europeans and the rest of Canada o Lifestyle and impact on Canada about 60-70 years Challenges with climate change and impact of the Inuit o Hunting for food on the sea; imported food are more expensive o Eliminating food source
IMPACTS ON HUNTING • Loss of sea ice means the animals are farther away o Traveling a greater distance is both dangerous and expensive • Loss of sea ice can lead to o Accidents on thin ice o More severe storms o Inadequate storage NORTHWEST PASSAGE • As of 2008, the NWP southern route has been navigable for a record 3 consecutive years o Northern deep draft channel had been navigable throughout its length for the first 2 years in recorded history • Bathurst Inlet Port and Road o Ice roads are melting faster and freezing later o Base metals cannot be flown out like diamonds and gold o No deep water port on our Arctic Coast Arctic Bay announced 2007 o Sovereignty •
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Political concern (connects through two international bodies of water) o Canada considers it internal Canadian waters No navigation of the passages because we do not know which parts are shallow or deep due to years of ice Canadian government is not willing to spend money to navigate it Should be concerned because of the amount of resources in the north Economical concern (no navigation increases risk of accidents of boats traveling through the north) o We do not have the capacity to contain environmental damages from ship wrecks from oils and gasoline in the cold weather Cannot get base metals out because no roads or railways o Izok has large deposit of lead and zinc Important for steel development Now owned by a Chinese development company Plan to build a road that connects to Bathurst Inlet where a port is planned to be built on the southern part What we miss is the quality of sea ice We lose out on multi-year ice Ice is rotating counter clockwise Older ice is being flushed out of the arctic Ice is not thick enough and it melts a lot quicker As ice melts, solar radiation reelects into the water, warming it up, causing the ice to melt more
