Chapt 2 Flashcards
Boreal biome
Largest region in North America call the boreal forest or taiga
Is a continuous belt from Yukon to labrador
Annual precipitation is much higher particularly in Ontario Quebec and labrador where it is more than double that found in the tundra
There is just continuous permafrost thus allowing deep route development and enhanced drainage
Caniferous trees predominate
What is the transition zone between the boreal biome in the grassland biome
The forest parkland
What is the closest boreal forest
Forms the principal natural vegetation in the boreal bio. It is a dense forest of mature fir spruce and pine cover the northern areas of seven provinces stretching from BC to Newfoundland and Labrador. The closest florist is also found in so the new plan and small parts of the Northwest territories.
What are the most common trees in wetlands
On well drained land?
Black spruce and larch
Species of spruce fir pine and larch common along with strands of popular and Birch. Towards the southern limits Broadleaf trees particularly Aspen and Birch are found
What affects the east and western part of the boreal forest
Close proximity to the pacific ocean keeps temperatures of the western section of this biome relatively high while frozen Hudsons bay reinforces the cold continental affect on the winter temperatures of the eastern part of the boreal forest
Podzolic soil
The thin acidic podzolic soils are formed under cool, wet growing conditions were the principal vegetative litter is derived from a coniferous forest
Are associated with discontinuous and sporadic permafrost, both of which have relatively thick active layers
Gleysolic soil
Associated with extremely poorly drained and often water logged soul such as marshes and bogs. A low evaporation rate, immature drainage, and permafrost ensure an excess of ground moisture, resulting in severely leached soils and the widespread occurrence of ponds, lakes, bogs.
What are the four climatic subtypes of the polar climate
The arctic, sub arctic, mountain, and ice Climates
Each climatic type is associated with an air mass that reflects the weather characteristics of that type. As this air masses move across the continent they affect weather in other regions
What is albedo?
Reflective quality.
What are the two layers of permafrost
The upper layer of permafrost call the active layer, does each summer and then re-freezes each winter. The thickness of the actively are very sore if you centimetres in the tundra biome to five or more metres in the boreal bio
The lower layer of permafrost never thoughts, but towards southern limits pockets of permafrost exist where the active player may reach 5 m
Since permafrost berries in depth and geographic extent, it is divided into four types. What are these types?
Continuous where over 80% of the ground is permanent frozen. Found where the mean annual temperature is around -7
Discontinuous 30 to 80% must be frozen. Found were the mean annual temperature is between -5 and -7
Sporadic less than 30% of the ground in an area is permanently frozen. This zone represents a transition area between permanently frozen and unfrozen ground. Found were the mean annual temperature is between zero and -5
Alpine permafrost is not defined by the percentage of permanently frozen ground but by its presence in a mountain is setting
How does permafrost affect the biophysical environment
By slowing the gross of vegetation, impeding surface drainage, and creating Perry glacial landforms. More specifically, active layer thickness influences root systems and soil moisture conditions. In this way permafrost shapes a landscape, vegetative community and ecosystems. It also affects northern hydrology through its influence on infiltration, run off, groundwater storage and rivers
What is a Thermokarst landscape
Characterized by very irregular surfaces caused by melting of ice rich frozen ground. As the claimant continues to warm, the degradation of permafrost is expected to accelerate, resulting in more thermokarst landscapes
Periglacial landforms
Look it up
Gelifluctiom
Another example of permafrost all to reading the landscape is through a special form of Solifluction known as gelifuction. Sloping land is prone to slumping when the active layer become saturated with melting water and the entire mess slowly slides down the permanently frozen slope
What are the four drainage basins
The arctic, Hudsons bay, Atlantic, and Pacific basin the river systems found in each drainage basin empty into the three ocean surrounding Canada the Arctic and Hudson Bay drainage basins form nearly 75% of the area of Canada and, despite relatively low precipitation, These two basin’s account for 50% of the streamflow
What is the largest river in Canada
The McKenzie river is just over 4200 km in length making at the 10th largest river in the world. In terms of run off volume, McKenzie river is by far the most important river in the north. Since most of the headwaters are located in BC Alberta and CISC actual in spring melting first occur south of the 60th parallel while the lower reaches of the McKenzie river are still frozen. Ice jams frequently occur, causing widespread flooding. Yet, this ice jams affect the McKenzie delta in a positive way by replenishing tens of thousands of lakes, ponds and wetlands in the region
What is arctic oscillation
The ice pack is not attached to land in there for moves in a clockwise motion within the Arctic Ocean
What is the difference between pack ice and land fast ice
Polar pack ice is much thicker and harder than new ice, which forms to join the Arctic ice pack but melts each summer. Land-fast ice is a common form of new ice. Land fast ice is attached to coasts and extends offshore over shallow parts of the continental shelf. Unlike the polar pack ice, land- fast ice remains fixed in location will pack ice drifts, driven by currents and winds
What did the seas of the Canadian North extend from
From Beaufort seas to the Labrador sea and include the waters of Hudsons Bay
Why do the seas of the Canadian north have less impact on the northern hydrological cycle that might be expected
Cold season see ace have a Luer of affirmation rate that warm seats, thus limiting moisture forming an arctic air masses
The circulation of the Arctic Ocean is relatively isolated from the rest of the world current because the Beaufort gyre circulation system tends to limit flow to the Atlantic and Pacific ocean and because of the cold water.
Due to climate change the circulation system is weakening thus leading to greater interaction with the Atlantic Pacific oceans
What is a polynya
During winter, when there is extensive ice cover, A polynya or open water area exists l in northern part of baffin bay it is still unsure why this happens
What are the fivegeomorphic regions
The Canadian Shield, the cordillera, the interior plains, the Hudson’s Bay low lands, and the Arctic lambs
What affected the five north in regions
Glaciatiom during the late Wisconsin periode Effect of the five north in regions by modifying the surface either directly, by glacial erosion or deposition, or indirectly, by the formation of glacial lakes and by the invasion or depressed lands by seawater
What are erratics
Huge boulders move the great distances and then deposited on the ground one example of the power of glacial erosion
Nunataks
Are mountain peaks at rose above the alpine glacier
What is the geological core of the northern landscape
The Canadian Shield, stretching from labrador to the NWT, is the largest geomorphic region in the Canadian North, it’s Precambrian rocks are more than two .5 billion years old and Iie benath most of the more recently formed Strata such as the interior plains and the Hudson’s Bay lowlands
The interior plains
A flat to gently rolling land scape. The sedimentary rocks of the interior plains were formed after the end of the Precambrian era and include cretaceous age of rocks formed 100 million years ago within these cretaceous aged rocks, vast oil, gas, and potash deposits exist. At the end of the last glacial Advance, the mantle of glacially deposit debris or glacial till cover do you sedimentary rocks. In other places, glacial lakes drained, forming flatland consisting of glaciolacustrine material, while outwash planes resulted from meltwater streams that deposited glaciofluvial materials. Fast flowing rivers fed by the melting ice sheet carved deep valleys known as glacial spillways
What are the two huge detaic landforms of the McKenzie river
One isis at the western end of the lake Athabasca, where the peace and Athabaska River’s deposit their silt. The other is the McKenzie Delta, located at the mouth of the McKenzie river
The cordillera
To geologic forces, known as faults and folds, created it’s basic landform features, and erosional agents, primarily ice and water, reshaped these features. It contains what are today remnant glaciers and ice fields. This geomorphic region has majestic mountains include in the world famous Rocky Mountains. These mountains were formed by severe folding and faulting of sedimentary rocks
The Hudson Bay low lands region
Consists of low, flat coastal Plains that, do geologically speaking, emerged recently from the Tyrell sea . The surface of this lowland consists of recently deposited marine sediments combined with reword glacial till. These deposits accumulated in the post glacial periode when the lowland was beneath the tyrell sea.
With the retreat of the ice sheet from this area, the process of isostatic rebound came into play. More and more of these seabeds became land as the surface of the earth gradually rose after having been depressed by the massive weight of the ice sheet
Isostatic uplift or isostatic rebound
With the removal of the weight of the ice sheet, the earths surface begin to regain its former shape. Assuming that the rate of isostatic uplift remains around 70 to 130 cm per hundred years Hudsons bay could become a fraction of its present size this does not account for rising sea levels
The arctic lands
Complexed you more for Gary is centred on the Arctic archipelago
Created low lands, hilly terrain, mountains and even Polar deserts
What three things causes polar deserts
Low precipitation continuous permafrost a long periods when the sun does not appear
What is the primary geomorphic process in the Arctic lands
Frost action it results in many Perry glacial features such as Pingo’s and tundra polygons
Where are most of Canada! Found
Found in the mountainous terrain of the eastern section of Queen Elizabeth islands especially Ellesmere island
Which two huge ice sheets covered most of Canada during the last glacial advance of the place to see in epoch
The Laurentide and the Cordillerathese a Sheetz reached a maximum thickness of 4000 and 2000 m today the largest glacier is 1000 m
What is glaciation
One of the principal erosional agents that have fine-tuned a variety of landscapes in Canada’s north it involves the formation, advance, and retreat of glaciers
During the process of advance and retreat two geomorphic processes take place. First the advancing ice sheets cause glacial erosion; later the retreat ice sheet deposited to Debris on the land
What are cirques and arretes
- Basins carved by the glaciers
2. Razor like ridges
What is a glacial till
Consists of unsorted material deposited by a melting a sheet for glacier
What is an Esker
Long, narrow ridges of sorted sand and gravel were deposited from melt streams within or beneath decaying ice sheet
What is a drumlins
Formed by massive sub glacier flooding, appear as clusters of low elongated whale backed hills shaped by the flow of the ice
Recorded the final direction of the ice movements
What are Peri glacial features
They exist in a dry cold environment where permafrost is widespread. It’s landform features are often moulded by the process of freezing and thawing out. The most distinctive Perry glacial landform or ice cored hills known as Pingos
What are Pingos
Associated with permafrost and cold dry arctic climate or frost action is the dominant geomorphic process.
Occur in the low lands were continuous permafrost exists and are formed when an ice lenses permanently frozen ground is nourished by extraneous water. Over time, but ice lens grows and pushes it self upwards forming a mound and eventually a hill
What is the most common perry glacial feature
Patterned ground. Symmetrical forms, usually polygons, caused by intense frost action over a long period of time. The general process of frost heaves causes course Stones to move to the surface and out words
