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Landforms for Legends

Landforms for Legends. The Science Behind Landforms That Legends Are Made From . Table of Contents. Icebergs on the Alsek Snowrollers Tufa Mounds The Hoodoos The Okotoks Erratic Eskers Pingos Red River Floods Indian Summer The Giants of the Forest. Ice Storms The Great Lakes

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Landforms for Legends

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  1. Landforms for Legends

    The Science Behind Landforms That Legends Are Made From
  2. Table of Contents Icebergs on the Alsek Snowrollers Tufa Mounds The Hoodoos The Okotoks Erratic Eskers Pingos Red River Floods Indian Summer The Giants of the Forest Ice Storms The Great Lakes Tides of the Bay of Fundy Red Soil of PEI Atlantic Hurricanes Permafrost of the Arctic Turtle Mountain—Frank Slide The Arctic Ice Pack Niagara Falls Tornadoes Avalanches
  3. Alsek River--Icebergs The Alsek river in the Kluane National Park Reserve (Yukon—Cordillera). The Lowell Glacier (one of the longest in the world) forms a large section of the Alsek Valley wall. The Glacier calves dropping large chunks of ice into the river (the icebergs).
  4. Iceberg in Alsek River
  5. Icebergs in Alsek River
  6. Snow rollers Interior Plains Snow rollers are a very rare phenomenon where snowballs form naturally by a very strong wind blowing across a flat, snow covered field when the snow is easily compacted (snow temperature near 0degrees C).
  7. Snow rollersInterior Plains These are formed under specific weather conditions: The ground surface must have an icy, crusty snow, on which falling snow cannot stick. About an inch or so of loose, wet snow must accumulate. Gusty and strong winds are needed to scoop out chunks of snow.
  8. Tufa Mounds at RabbitKettleHotsprings Nahanni National Park-- Cordillera Tufa Mounds are found in the mysterious Nahanni River Valley Tufa mounds are created by the precipitation of dissolved minerals, primarily calcium carbonate, from thermal spring water.
  9. Tufa MoundsRabbitkettle Hot SpringsNahanni National Park People are not allowed to wear shoes in this area.
  10. Tufa Mounds
  11. Hoodoos—Drumheller ABInterior Plains Hoodoos take millions of years to form and stand 5 to 7 metres tall. Each hoodoo is a sandstone pillar resting on a thick base of shale that is capped by a large stone. Hoodoos are very fragile and can erode completely if their capstone is dislodged (in other words, no climbing allowed).
  12. The Hoodoos
  13. The Hoodoos are found in North American badlands, formed by wind and water erosion of sedimentary rocks. Looking like petrified mushrooms, they have a protective rock cap which shelters their shaft, detering them from disintergrating at the same speed as the surrounding sandstone.
  14. Glacial RockOkotoks AB—Interior Plains "The Big Rock" is the world's largest known glacial erratic--rock transported far from its place of origin by glacial ice. Big Rock, also known as the Okotoks Erratic, is the largest rock in the Foothills Erratics Train, a group of rocks that were carried by ice along the mountain front and dropped as the glacier melted some 10,000 years ago. The erratics lie in a narrow band extending from Jasper National Park to northern Montana. The Okotoks Erratic weighs 16,500 tons. It measures 9 metres high, 41 metres long and 18 metres wide.
  15. Big Rock was originally part of a mountain (likely Mount Edith Cavell) in what is now Jasper National Park. About 18,000 years ago, a rockslide crashed material to the surface of a glacier in the present day Athabasca River valley, and Big Rock was carried out of the mountains on the glacier's back. The valley glacier slowly moved eastwards to the plains, where it collided with a continental glacier, the great Laurentide ice sheet. The valley glacier was redirected to the southeast, parallel to the mountain front. The erratics were deposited as the ice melted.
  16. OKOTOKS ERRATIC
  17. ESKERS IN N.W.T.CANADIAN SHIELD Just as rivers on land carry and deposit sediment, melt water that flows in the openings beneath, above and within a glacier also carries and deposits sediment.
  18. Tunnels near the base of retreating glaciers fill with transported sediments, which remain as sandy or gravelly ridges that look like upside-down stream beds after the glacier melts away. The ice that formed the sides and roof of the tunnel subsequently disappears, leaving behind sand and gravel deposits in ridges with long and sinuous shapes.
  19. Esker on the Manitoba/N.W.T Border Eskers can be 500 to 600 kilometres long and, depending on the pattern of the glacier's inner tunnels, can interconnect in a pattern of central ridges and tributaries, just like a branching river system
  20. PINGOS in the NWT Interior Plains Permafrost in the Arctic In the Arctic, the land stays so cold that a portion of the soil freezes in winter but never thaws out in the summertime. Called permafrost, this soil creates a hardened barrier at the top of the ground. (see reference 1) Pingos resemble large bubbles in the Arctic, and as their formation closely mirrors that of acne, they often are called "Earth pimples." (see reference 1)
  21. Beneath the Arctic ground, under the permafrost, natural springs exist. Just as in other portions of the world, these springs attempt to find an outlet on the surface, but the permafrost blocks their route. In the same way that holding a finger over a garden hose increases the water pressure, the permafrost also raises the pressure of the water. This pressurized water holds the key to pingo formation.
  22. Pingos also form when lakes dry out. The soil around the lake contains deeper layers of permafrost, but the bottom of the lake did not freeze in the winter. Even after most of the water in the lake evaporates, the bed remains slightly damp. This moisture holds the source of a future pingo.
  23. http://arctic.fws.gov/permcycl.htm The above link is to an animation that explains the development of a pingo. Pressure from the spring pushes upward on the soil. Should it find a weakened area of a thinner layer of permafrost, the water seeps in and expands upward as it freezes. This forces the soil to create a bubble by being pushed upward from the ice beneath. The frozen water inside the pingo creates an ice core, which increases the size of the pingo as it grows. As more water feeds into the soil and freezes, the bubble gets bigger. Pingos can range in size from a car to a small mountain, but they all have frozen ice at their center.
  24. The Red River Floods The grey color at the top of the image (below the skyline is all water. This is Morris Manitoba.
  25. The Red River Floods--1950 The 1950 Red River Flood was a devastating flood that took place in Winnipeg, Manitoba, on May 8, 1950. In that year, the Red River flooded the Red River Valley. Winnipeg was ill prepared for such a huge swell of water. Eight dikes gave way and flooded much of the city. Four of eleven bridges were destroyed and nearly 70,000 people had to be evacuated from their homes and businesses. There was one fatality on May 6, 1950, when Lawson Ogg was trapped in a basement where he was fixing a pump when waters rushed through the door of the house and filled the basement. The final tally in damage was over $600 million. The Red River Floodway was later constructed to divert some of the water of the Red River around the city and lower water levels within Winnipeg.
  26. The shaded area on the map shows the extent of the flooding of the Red River and its tributaries. At the peak of the flood more than 550 square miles in the Red River Valley from Emerson to 60 miles north to Greater Winnipeg were flooded. The depth of the flood waters on the farmland was between 2 to 6 feet. The black line is the normal channel of the Red River. See separate powerpoint for more images.
  27. Indian Summer In The Great Lakes—St. Lawrence Lowlands Region An Indian summer is a meteorological phenomenon that occurs in November or later, in the Northern Hemisphere. It is characterized by a period of sunny, warm weather, after the leaves have turned or fallen and there is no snow cover on the ground.
  28. Traditional vs Modern Indian Summer Traditionally, Indian summer can only be a true Indian summer in January during warm temperatures when the ground is not covered in snow. Modern Indian Summers are highlighted by beautiful fall colors in the native trees.
  29. Giants of the Forest—Douglas FirCordillera Region The Douglas Fir can reach up to 85 metres in height on the coast and 42 metres in the interior. The Douglas Fir is named after the Scottish botanist, David Douglas, who introduced many of BC's native conifers to Europe
  30. Giants of the Forest—Douglas FirCordillera Region
  31. The Douglas Fir The Douglas Fir grows on the southern mainland coast of British Columbia and Vancouver Island An interior variety of the Douglas Fir is found throughout southern and central BC
  32. ICE STORMSSt. Lawrence Lowlands & Great Lakes Region
  33. Casualties and Damage from the Ice Storm of 1998: Great Lakes—St. Lawrences Lowlands Region For six days in January 1998, freezing rain coated Ontario, Quebec and New Brunswick with 7-11 cm (3-4 in) of ice. Trees and hydro wires fell and utility poles and transmission towers came down causing massive power outages, some for as long as a month. It was the most expensive natural disaster in Canada. According to Environment Canada, the ice storm of 1998 directly affected more people than any other previous weather event in Canadian history. 28 people died, many from hypothermia, 945 people were injured. Over 4 million people in Ontario, Quebec and New Brunswick lost power. About 600,000 people had to leave their homes. 130 power transmission towers were destroyed and more than 30,000 utility poles fell. Millions of trees fell, and more continued to break and fall for the rest of the winter. Estimated cost of the ice storm was $5,410,184,000.
  34. Ice Storm Facts By June 1998, about 600,000 insurance claims totalling more than $1 billion were filed. Summary of Ice Storm of 1998: Freezing rain started on Monday, January 5, 1998 as Canadians were starting back to work after the Christmas holidays. The storm coated everything in glassy ice, making all forms of transportation treacherous. As the storm continued, layers of ice built up, weighing down power lines and poles, and causing massive power outages. At the height of the ice storm, 57 communities in Ontario and 200 in Quebec declared a disaster. More than 3 million people were without power in Quebec and 1.5 million in Eastern Ontario. About 100,000 people went into shelters. By Thursday, January 8, the military was brought in to help clear debris, provide medical assistance, evacuate residents, and canvass door-to-door to make sure people were safe. They also worked to restore power.
  35. Ice Storms Facts Power was restored in most urban areas in a matter of days, but many rural communities suffered for much longer. Three weeks after the beginning of the storm, there were still 700,000 people without power. Farmers were especially hard hit. Nearly a quarter of Canada's dairy cows, a third of the crop land in Quebec and a quarter in Ontario were in the affected areas. Milk processing plants were shut, and about 10 million litres of milk had to be dumped. Much of the sugar bush used by Quebec maple syrup producers was permanently destroyed. It was estimated that it would take 30 to 40 years before syrup production could return to normal.
  36. Ice Storms in the Great LakesSt. Lawrence Lowlands Region
  37. The Great Lakes: Great Lakes—St. Lawrence Lowlands Region Represent the largest body of fresh water (not salty) in the world. They were created by the Lauren tide glaciers when they melted 14,000 years ago.
  38. The GREAT LAKES Lake Superior 82,000 sq km, 31,698 sq miles in size, is the largest fresh water lake in the world. It is about 350 miles (565 km) long and 160 miles (257 km) at its widest point. The deepest point is 1,332 ft, while the average depth is 500 ft. Shoreline: 2,730 miles (includes islands) Lake Michigan 57,800 sq km, 22,316 sq miles in size, is the largest freshwater lake (totally within) the United States. It is 307 miles (494 km) long and 118 miles (190 km) at its widest point. The deepest point is 925 ft, while the average depth is 279 ft. Shoreline: 1,640 miles (includes islands)
  39. The Great Lakes
  40. Great Lakes Lake Huron 59,600 sq km, 23,011 sq miles in size, is 206 miles (332 km) long and 183 miles (295 km) at its widest point. The deepest point is 750 ft, while the average depth is 195 ft. Shoreline: 3,830 miles (includes islands) Lake Erie 25,700 sq km, 9,922 sq miles in size, is 240 miles (386 km) long, and 38-57 miles (61-92 km) wide. The deepest point is 210 ft, while the average depth is 48 ft. Shoreline: 871 miles (includes islands)
  41. Tides of the Bay of Fundy The Appalachian RegionHopewell Rock Low and High Tide The height of the tide difference ranges from 3.5 meters (11ft) along the southwest shore of Nova Scotia and steadily increases as the flood waters travel up the 280 km (174 miles) of shoreline to the head of the Bay where, in the Minas Basin, the height of the tide can reach an incredible 16 meters (53ft). The time between a high tide and a low tide is, on average, six hours and 13 minutes.
  42. How the Tides Occur Tides are considered the heartbeat of our planet’s oceans. They are the periodic rise and fall of the earth’s bodies of open water, and are a result of the gravitational pull of the moon and sun on the earth, as well as the perpetual spinning rotation of the earth itself. By far the largest influence is the gravitational effect of the moon as it pulls the water toward itself, making a bulge on the surface of the ocean at the side of the moon (lunar tide). The Reversing River in New Brunswick, caused by the tides.
  43. The Same Harbor in Nova Scotia At the same time, the centrifugal force (caused by the spinning of the Earth-Moon system) acting on the water particles at earth’s surface opposite the moon, creates a second bulge. These bulges are what we refer to as high tide. As the moon rotates around the earth the bulges shift with it causing a shift in the water level.
  44. The Red Soil of PEIAppalachian Region Red Sandy Beaches Did you know P.E.I. has over 800 km of sandy shoreline that is filled with red and pink (yes pink!) beaches? But why does P.E.I. have red sand instead of the usual white or brown?
  45. Red Soil—Great Potatoes Prince Edward Island was formed a long time ago on sedimentary bedrock of soft, red sandstone, which produces rich, red soil. The soil is red because it has a lot of rust in it. This soil is excellent for crops such as potatoes.
  46. Hurricanes from the Atlantic Hurricane Igor—the white spinning object displayed in the Atlantic is Igor, it is bigger than New Brunswick.
  47. How Hurricanes Are Formed Hurricanes are products of a tropical ocean and a warm, moist atmosphere. Powered by heat from the sea, they are typically steered by the surrounding deep layer (from the ocean’s surface to 8 miles up) easterly winds, generally south of 25° north latitude and by high-level westerly winds north of 25° north latitude. The process by which a disturbance forms and strengthens into a hurricane depends on at least three conditions. First, a disturbance gathers heat and energy through contact with warm ocean waters. Next, added moisture evaporated from the sea surface powers the seedling tropical storm like a giant heat engine.
  48. Third, the seedling storm forms a wind pattern near the ocean surface that spirals air inward. Bands of thunderstorms form, allowing the air to warm further and rise higher into the atmosphere. If the winds at these higher levels are relatively light, this structure can remain intact and further strengthen the hurricane. The center, or eye, of a hurricane is relatively calm with sinking air, light winds and few clouds. The most violent winds and rain take place in the eyewall, the ring of thunderstorms immediately surrounding the eye. At the top of the eyewall (about 50,000 feet), most of the air is propelled outward, increasing the air’s upward motion. Some of the air, however, moves inward and sinks into the eye, creating a cloud‑free area.
  49. Hurricane Igor
  50. Storm Surge In any case, whether in the area of extreme danger to the right in the northern/left in the southern hemisphere of where the center moves ashore, or well away from the center on the fringes of the storm, the surge of high water topped by battering waves can be devastating. It is important to note that the stronger and larger the size of the hurricane and the shallower the offshore water, the higher the surge will be. Storm surge is by far the greatest threat to life and property along the immediate coast.
  51. Permafrost—A Northern Reality Permafrost is defined on the basis of temperature, as soil or rock that remains below 0°C throughout the year, and forms when the ground cools sufficiently in winter to produce a frozen layer that persists throughout the following summer. It is the ground below the top soil (which can thaw during the warmer summer months).
  52. The permafrost in the Arctic can be up to 50 metres deep. As you go deeper into the earth’s crust the rock gets warmer due to the molten material (mantle) found beneath the earth’s crust (that produces the lava for volcanoes).
  53. How Building are Constructed on Permafrost Since you can not create a foundation for buildings in the traditional manner (basement) buildings are built on stilts to keep them level.
  54. TURTLE MOUNTAIN--The Frank Slide http://www3.sympatico.ca/goweezer/canada/frank.htm The link above tells the entire story about the Frank Slide.
  55. Picture Taken Immediately after the Rock Slide Occurred on Turtle Mountain In the early morning hours of April 29, 1903, Turtle Mountain collapsed, resulting in the greatest landslide in North American history. In 100 seconds: at least 76 people were buried alive under tons of massive limestone boulders; three-quarters of the homes in Frank were crushed like balsa wood; over a mile of the Canadian Pacific Railroad was completely destroyed; and a river became a lake.
  56. TURTLE MOUNTAIN AFTER THE SLIDE Survivors described a cracking sound like cannon fire echoing throughout the mountains. A 640 metre high, 915 metre wide, 152 metre thick (2,100 feet by 3,000 feet by 500 feet) wedge of the eastern slope of Turtle Mountain gave way and slid 700 metres (2,300 feet) down the mountain side. An estimated one hundred million tons of limestone slid into the valley and onto the town of Frank.
  57. Map of The Turtle Mountain Area
  58. The GREY Area is the Slide Damage
  59. The Arctic Ice Pack In winter, seawater freezes and forms a crust of ice called "pack ice". The area of floating ice, which makes up much of the ice cap in the Arctic Ocean, expands during winter to cover about 5% of the northern oceans and 8% of the southern oceans.
  60. The Arctic Ice Pack Pack ice consists of ice that formed both at sea and as fast ice (locked to the shore). It can be very flat (because the ocean is flat), but it is usually covered with very rough areas caused by the movement of sheets of ice against one other. These pressure ridges can increase the thickness of the ice from just a few inches or centimeters to tens of meters (many feet) thick.
  61. The Arctic Ice Pack Although pack ice moves with ocean currents and wind, it is not free-floating like ice-floes, and it is not always continuous. At times it can be very broken, with leads (cracks of open water) opening up without warning. The leads then refreeze, adding new ice throughout the winter. The ice pack is the home for polar bears and the walrus.
  62. How New Ice is Formed
  63. The Ice Pack in Feb. vs Sept. SEPTEMBER FEBRUARY
  64. Niagara Falls The water over the Niagara Falls comes from four of the five (fresh water) Great Lakes. From Niagara Falls, water flows down the Niagara River merging with the waters of Lake Ontario, then into the mighty, St. Lawrence River located in northeast Canada. These fresh waters eventually flow north into the Atlantic Ocean.
  65. Horseshoe Falls is on the Canadian side of the border. length of brink: 2600 feet height: 167 feet volume of water: 600,000 U.S. gallons per second
  66. AMERICAN FALLS length of brink:  1060 feet height:  176 feet  (due to rocks at the base actual fall is 70 feet) volume of water: 150,000 U.S. Gallons per second
  67. HISTORICAL FACTS The Falls at Niagara are about 12,000 years old Falls were formed when melting glaciers formed massive fresh-water lakes (the Great Lakes) one of which (Lake Erie) ran downhill toward another (Lake Ontario). The rushing waters carved out a river in their descent and at one point passed over a steep cliff like formation (the Niagara escarpment). From the original falls going over the Niagara Escarpment, the water began to wear its way back up the river. The path that it left is known today as the Niagara Gorge (a deeply-cut and very scenic river path
  68. NIAGARA FALLS USA
  69. HORSESHOE FALLS
  70. Tornadoes Tornadoes are relatively common in Canada, but only in specific regions: southern Alberta; Manitoba and Saskatchewan; southern Ontario; southern Quebec; the interior of British Columbia; and western New Brunswick. Tornado season extends from April to September with peak months in June and July, but they can occur at any time of year. F5 Tornado in Manitoba 2007
  71. Pine Lake Alberta--2000 Canada gets more tornadoes than any other country with the exception of the United States. Tornadoes are rotating columns of high winds. Sometimes they move quickly (up to 70 km/hour) and leave a long, wide path of destruction. At other times the tornado is small, touching down here and there. Large or small, they can uproot trees, flip cars and demolish houses. Tornadoes usually hit in the afternoon and early evening, but they have been known to strike at night too.
  72. Natures Most Violent Storms Black Friday—Edmonton 1997: The tornado remained on the ground for an hour, cutting a swath of destruction 40 kilometres (25 miles) long and up to a kilometre (0.6 miles, or 3000 feet) wide in places, and peaking at F4 (some suggest F5 was reached).
  73. Tornadoes—The Deadliest
  74. What Causes a Tornado? Tornadoes form in unusually violent thunderstorms when there is sufficient (1) instability and (2) wind shear present in the lower atmosphere. Instability refers to unusually warm and humid conditions in the lower atmosphere, and possibly cooler than usual conditions in the upper atmosphere. Wind shear in this case refers to the wind direction changing, and the wind speed increasing, with height. An example would be a southerly wind of 15 mph at the surface, changing to a southwesterly or westerly wind of 50 mph at 5,000 feet altitude. This kind of wind shear and instability usually exists only ahead of a cold front and low pressure system. The intense spinning of a tornado is partly the result of the updrafts and downdrafts in the thunderstorm (caused by the unstable air) interacting with the wind shear, causing a tilting of the wind shear to form an upright tornado vortex. Helping the process along, cyclonically flowing air around the cyclone, already slowly spinning in a counter-clockwise direction (in the Northern Hemisphere), converges inward toward the thunderstorm, causing it to spin faster. This is the same process that causes an ice skater to spin faster when she pulls her arms in toward her body.
  75. What Causes a Tornado? Other processes can enhance the chances for tornado formation. For instance, dry air in the middle atmosphere can be rapidly cooled by rain in the thunderstorm, strengthening the downdrafts that are needed for tornado formation. Notice that in virtually every picture you see of a tornado the tornado has formed on the boundary between dark clouds (the storm updraft region) and bright clouds (the storm downdraft region), evidence of the importance of updrafts and downdrafts to tornado formation.
  76. Avalanches http://video.nationalgeographic.com/video/player/environment/environment-natural-disasters/avalanches/avalanches.html
  77. Avalanches can be anything falling down the side of a mountain. Snow avalanches can be dangerous because of the power of the snow falling. They can happen at almost any snow covered mountain at any time. In the United States and Canada, avalanches happen in the Pacific Mountains and the Rockies. Over 100,000 occur in North America. They mostly happen where there are few trees.
  78. Where Do Avalanches Occur? About 90% of all the avalanches begin on slopes between 30 to 45 degrees; about 98% of all the avalanches occur on slopes between 25 to 50 degrees. Avalanches start most often on slopes above the timberline that face away from prevailing winds. Avalanches can run, however, on small slopes well below the timberline, such as gullies, road cuts, and small openings in the trees. Very dense trees can anchor the snow to steep slopes and prevent avalanches from starting; however avalanches can release and travel through a moderately dense forest. Most avalanches occur in the backcountry, outside of developed ski areas.
  79. There are two common types of avalanches, a Surface Avalanche that occurs when a layer of snow with different properties slides over another layer of snow. For example, when a layer of dry loosely packed snow slides over a dense layer of wet snow. The other common avalanche is known as a Full-Depth Avalanche which, as it’s name would lead you to believe, occurs when an entire snow cover, from the earth to the surface, slides over the ground.
  80. Avalanche Dangers Between a wet and dry snow avalanche, the dry one is more dangerous. It can travel as fast as 120 mph while the wet snow avalanche can go for just 5 mph or less. Dry snow avalanche can create a force as powerful as an explosive. Most people who encounter this avalanche suffer from injuries, either they are dragged through trees and cliffs or they get hurt by their own equipment (snowmobile, snowboard, etc.).
  81. Tragically, a person gets buried completely in snow after being taken by an avalanche. Suffocation would be the biggest danger a person has to face with being buried in snow. Avalanche debris is compact and heavy unlike how it used to start – light and fluffy. The moment the snow stops from moving, the kinetic energy from the moving snow creates heat from fiction that makes it hard and heavy. One cannot contain the weight of the snow. Therefore, it can squeeze the person, especially his or her lungs. One may be buried alive – lacking oxygen and being frozen by snow.
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