FRESHWATER:Naturally occurring water that lacks the salt content found in seawater.
Lakes
Rivers
Ponds
Streams
Underground aquifers
FRESHWATER SOURCES
The water cycle is a cycle of processes by which water circulates between the earth's oceans, atmosphere, and land. When water evaporates from the oceans it moves over land and deposits as precipitation:
Rain
Snow
Fog/Dew
Higher elevation land (Ex. Mountains) have lower temperatures, when clouds (water condensation) moves over elevated lands they will deposit much more precipitation. (aka - Mountains receive more rain and snow) Rain water collects in small streams, this flow is always from higher elevations to lower elevations. Snow also collect in large glaciers which melt throughout the spring/summer.
GLACIERS
GLACIERS :Large moving body of ice, glaciers can be many meters or even kilometres thick, and stores vast amounts of freshwater.
Glaciers that cover vast areas of land are called continental glaciers or icecaps.
Glaciers form in the cold regions of Earth, they build up, and then start to move, which then are called valley glaciers because they flow between the mountains.
The valley glaciers collect huge or small pieces of rocks, which drag on the surface and determine the form of the land.
THE MOVEMENT OF GLACIERS DEPENDS ON THE CLIMATE.
Cooler – little melting, snow builds up, and the glacier moves forward and is considered to be “advancing”
Warmer – more melting, snow decreases, the glacier moves back and is considered to be “retreating”
RECOGNIZING GLACIAL FEATURES
Today, few continental and valley glaciers cover the Earth.
In the past, large areas of the Earth were covered, called the Ice Ages.
The Ice Ages shaped most of Canada’s geography.
GLACIAL FEATURES INCLUDE:
Moraines
Eskers
Drumlins
Kettle lakes
WHAT IS A WATER SHED?
WATERSHED: An area of land that drains into one main lake or river.
A watershed can contain many smaller rivers and lakes.
Think of a watershed draining into a river being the same as a funnel that collects water and drains it into a pipe
The “vertical edges” of a watershed are elevated areas (Mountains / Hills)
CONTINENTAL DIVIDE: The highest point of land on a continent; rivers flow into different oceans depending on which side of the divide they begin.
In Canada the continental divide is the Rocky Mountains.
The red line on the map divides North America into East and West.
If water rains west of the divide it will end up flowing into the Pacific Ocean
If water rains east of the divide it will end up flowing into the Atlantic Ocean
There are other divides in North America that contribute to the direction water flows
CONTINENTAL DRAINAGE SYSTEMS
The same forces that shape the ocean basins also build the continental divides.
At the edge of the continent, two plates meet and push against each other, which cause wrinkles in the continent’s surface to push upward and form mountain ranges.
Plate tectonics have formed many continental divides.
LIFE OF A RIVER
Most streams originate in higher elevations such as mountains or high grounds
Streams steadily increase in volume of flow as they move from mountains to hills
As streams flow into lower areas, smaller streams begin to combine to form rivers
Over time rivers slowly begin to twist and turn, this erodes the nearby river banks forming valleys (river is meandering)
As river waters begin to slow the farther it travels from its source it deposits rocks and minerals into the riverbed
River eventually forms collects into a lake, or flows into the ocean
RIVER AND STREAM CHARACTERISTICS
IDENTIFYING THE CHARACTERISTICS OF A STREAM OR RIVER IS USEFUL BECAUSE IT HELPS:
Scientists understand types of organisms living in the waters.
Scientists hypothesize the impact of human activities on these waters.
Engineers use stream characteristics to understand how to build bridges and dams.
STREAM ZONES
Erosion Zone (aka Headwaters)
Fast moving water
Large sediments enter the water
Transfer zone
Water moving at a slower pace
sediment is moved along river
Depositional Zone
Water moves very slowly
Sediment is deposited and collected at the bottom of the river
RIVER DELTA:A landform created by deposition of sediment that is carried by a river as the flow leaves its mouth and enters slower-moving water (ex. lake, ocean)
DESCRIBING STREAM CHARACTERISTICS
RESEARCHERS ORGANIZE A RIVER OR STREAMS CHARACTERISTICS WITH A PROFILE.
STREAM CHARACTERISTICS :Characteristics used to describe a stream or river; these include: THE CHARACTERISTICS OF A STREAM’S SHAPE
Speed of flow (how fast is the river flowing)
fast, moderate, slow, crawling
Quantity of water (amount of water flowing)
vast (Amazon River), large (North Sask. River), moderate (Bow River), small (Elbow River), trickle (mountain brook)
Stream shape (does it flow straight or does it curve back and forth)
straight, sinuous, meandering
Stream slope (affects speed of water flow)
steep, moderate, gentle
Riverbed shape (how does the bottom of the river look)
V shaped, U shaped, flat, shallow
Stream width (how wide is the river)
wide, intermediate, narrow
Stream bank (tall steep cliffs - not much erosion, valleys eroded over time, deltas form via deposition)