Water Systems Unit- Test Taking Ticket (T3)
Earth’s Supply Of Water:
Saltwater: Saltwater fills oceans and makes up 97 percent of Earth's supply of water.
The concentration of dissolved salts in ocean water averages 3.5 percent.
Freshwater:
The only water we can drink is only 3 percent of Earth’s total supply, 97 percent of Earth's supply of water is saltwater which we cannot drink.
We can only drink 3 percent of the Earth's supply of water which is low.
Most of the planet’s freshwater occurs as ice and snow or moves through the ground below the surface.
Three States Of Water
Solid, Liquid, Gas
When water changes from one state to another, adding enough heat to liquid water it evaporates, transforming into a gas (Water Vapour).
Take enough heat away from liquid water and it freezes into its solid state (Ice).
Groundwater, Solid Water, Ice Sheets/ Iced Caps, Aquifer
Solid Water
All of the solid water (frozen) Water on Earth is all freshwater.
Ocean water can freeze, but salt water requires a lower temperature than fresh water to become ice.
The salt in saltwater does not freeze with the water, all ocean ice becomes frozen fresh water.
Groundwater
More of Canada's freshwater exists underground than on the surface.
Scientists estimate that one-third of the world’s freshwater lies underground.
The area where water fills all the air spaces in the soil and in the tiny cracks in the rock is called the groundwater zone.
This freshwater storage zone exists in all soils, but the depth differs from region to region. The upper surface of the groundwater zone is called the water table.
Some rock and soil layers exist in a way that allows large amounts of water to collect within them. This underground freshwater reservoir is called an aquifer.
Groundwater is always moving slowly out of your sight.
It eventually reaches to a wetland, river, lake, or ocean, or flows to the surface in what is called a natural spring.
When groundwater reaches the surface of a desert, an oasis forms.
Ice Sheets
An ice sheet is a large glacier that covers the land.
Only two of these huge glaciers on Earth, one in Greenland and one in Antarctica.
The term Polar Icecap is sometimes used to refer to these big ice masses at the poles.
Ice sheets are formed the same way as a mountain glacier but on a much larger scale
What is the Water Cycle and how does the Sun impact the cycle?
Water is constantly changing states as it moves from Earth’s surface into the atmosphere and back into the Earth again.
There is no beginning and no end to the water cycle.
The sun provides thermal energy that drives the whole cycle.
Water is not made in nature, it is recycled through the water cycle
- The sun’s heat energy drives the water cycle.
Water changes easily from one state to another by evaporation, melting, freezing, sublimation, condensations and deposition. Each change requires a transfer of energy.
When the sun reaches the Earth, it warms the atmosphere, land, ocean, and evaporates water.
Definitions
Evaporation: process of water changing from a liquid into water vapor (most common way)
Melting: process of solid ice becoming liquid (by adding heat)
Freezing: process of becoming ice by loss of heat
Sublimation: process of going from solid ice to water vapor without first becoming liquid (heat energy is absorbed)
Condensation: process of water vapor turning into liquid - this happens when vapor is cooled
Deposition: process when water vapor changes directly into a solid without becoming a liquid first (happens high in atmosphere where temps are very low -ex: frost)
Water Table and Water Sheds
A watershed is an area of land where all the water eventually drains into one main water body, such as a stream, river, wetland, lake, or ocean.
Activities that affect water in one part of the watershed therefore have an effect downstream in the watershed.
Small watersheds connect to larger watersheds and finally empty into an ocean.
North America has five ocean watersheds: the Arctic, the Atlantic Gulf Of Mexico, Hudson Bay, and the Pacific.
As water cannot flow uphill at high points the land such as mountain ridges creates natural “divides”, These are boundaries that direct where water flows.
For example, The Rocky Mountains act as a divide and are often referred to as the Great or Continental Divide.
In between these, there is a water table. Below the water table, there is only water filling the space between the soil particles. This is also known as the groundwater zone. Meanwhile, above, water and air fill the particles making it different.
What are Natural vs Human Factors that impact water quality?
Natural occurrences such as flooding , droughts, and earthquakes can cause changes in the height of the water table.
Overuse of wells has the potential to alter groundwater supplies permanently.
How much water we take from our environment and how we alter it before disposing of it can affect both the supply and the quality of water.
If more water leaves a watershed than enters it, a shortage will result.
The usual water levels in lakes and rivers will drop and the level of the water table will also drop as the amount of groundwater decreases.
If more water leaves a watershed than enters it, a shortage will result.
The usual water levels in lakes and rivers will drop and the level of the water table will also drop as the amount of groundwater decreases.
Flooding can damage property and can also cause water to be contaminated.
Mountain Glaciers
When temperatures are below freezing much of the year the snow that falls never gets a chance to melt
Over time, as the snow in the lower layers becomes more compact, most of the air spaces are squeezed out.
This creates a glacier which is a mass of ice and overlying snow that moves slowly down a mountain slope under the influence of gravity.