Hydrosphere Earth ‘s Water By Carla Thompson
Water World How is water distributed on earth? Two thirds (71%) of our planet is covered by water. 97.2% of the water is saltwater (found in oceans). Only 2.8% of the water on Earth is Freshwater The majority of freshwater is beyond our reach, locked into polar snow and ice. Less than 1% is available for consumption.
Question Time….. What percentage of the Earth is covered by water? 71% Or 3/4 What percentage of the hydrosphere is salt water? 97.5% What percentage of the hydrosphere is Fresh water? 2.8%
What is Salt water? Salt water is water that contains dissolved salts and other minerals. The water of the seas and oceans is salty Most human beings and other land animals can not survive by drinking salt water.
What do you think? Why do you think that most animals can’t survive by drinking salt water? (Hint: Osmosis) The only real reason is the salt. Your body is 97% water so it will dehydrate itself trying to get rid of all the excess sodium chloride (salt). The salt water has a LOWER concentration of water than your tissues. Osmosis will cause water in your tissues to flow from higher to lower concentration. So if you drink sea water, it will draw water OUT of your tissues and dehydrate you faster. IF you lose too much water, the concentrations of salt becomes too high and your muscles (like your heart) stop working right.
What is Fresh Water? Fresh water is water that is not salty and has little or no taste, color or smell Lakes, ponds, rivers, and streams are freshwater habitats. So too are swamps, bogs, and marshes.
Where we get our fresh water - Christiana Z. Peppard https://www.youtube.com/watch?v=Pz6AQXQGupQ
Were is most of the Earth’s water located? Most of the Earth’s water is salt water; therefore, most of the Earth’s water is located in the seas and oceans.
What makes up the Earth’s freshwater supply? The Earth’s freshwater is located in glaciers, icecaps, groundwater, lakes, rivers streams and reservoirs.
Question Time….. Where is most of the Earth's water found? Oceans / sea Where is freshwater located on Earth? icecaps, glaciers, groundwater and lakes, rivers and streams
Most fresh water on Earth is frozen
Most freshwater is located in glaciers and icecaps Most freshwater is located in glaciers and icecaps. Groundwater is the second most plentiful resource of freshwater. Surface water like lakes, rivers and ponds have the least amount of freshwater
What is a Glacier? It is an accumulation of fallen snow that, over many years, compresses into a large, thick, slow moving ice mass. It flows over land in Antarctica and the Arctic
What is an Iceberg? It is a large piece of freshwater ice that has broken off a glacier or an ice shelf and is floating freely in open water
How much of the iceberg is underwater? About 7/8 or over 90% of an iceberg's volume (and mass) is underwater
Freshwater flows Underground
What is groundwater? Fresh water that is held underground because it has soaked into the ground and percolated (water that is filter by porous rocks)
Question Time….. Why is consumable water considered scares on Earth? Because 97% of Earth’s water is salt water, only about 3% is available to drink. Of that 3% only about 1 % is accessible. Why is most of the Earth’s freshwater unavailable for consumption? About 2% of the Earth’s freshwater is in glaciers and icecaps
What properties does Earth’s soil have that allows it to absorb water? Permeability pore spaces allow a liquid to flow through it. Impermeable pore spaces are so close that water can not flow through it
What is the Water Table? Zone of aeration • pore spaces contain air the top of the zone of saturation where soil or rocks are mostly filled with water. Zone of saturation • pore spaces are filled with water
Water flows underground Due to gravity, water seeps into the ground and moves downward until the rock is no longer permeable. The subsurface zone in which all openings of the rock are filled with water is called the zone of saturation. This zone is also called an aquifer. The upper surface of this zone of saturation is called the water table. The zone that exists between the water table and the ground surface is called the zone of aeration. In order to be successful, a well must be drilled into the zone of saturation. Springs occur where water flows naturally from rock onto the surface of the land. Springs may seep from places where the water table intersects the land surface.
What type of groundwater feature is an aquifer? Underground bed or permeable rock layer that contains ground water for wells and springs etc… Types Artesian well- water flow to the surface naturally because it is under pressure Spring - water that flows to the surface of the earth from underground. It's a site where the aquifer surface meets the ground surface. water is between two permeable layers of rock water is between two impermeable layers of rock
Artesian Well Spring Types of Aquifers Wells needs a hole to be dug to access the water. A spring occurs at the water table so it doesn’t need a hole dug.
Question Time….. Give two reasons why ground water is important? 1. Groundwater is a significant part of the water cycle, containing 21 percent of Earth's freshwater. Groundwater comprises 97 percent of fresh water not tied up as ice and snow in polar ice sheets, glaciers , and snowfields. This greatly exceeds the amount of water in streams, rivers, and lakes. Groundwater is critically important in supplying water to streams and wetlands, and in providing water for irrigation , manufacturing, and other uses. In the United States, 80 to 90 percent of available fresh water comes from groundwater.
Fresh water also flows on the Earth’s surface
Fresh Water Locations—Rivers, Streams, and Lakes What is a stream? A small channel along which freshwater is continually flowing down a slope—made of small gullies. What is a river? A large channel along which water is continually flowing down a slope—made of many streams that come together.
How are ponds different from lakes? A ponds is generally smaller, very shallow and has many species of plants rooted in its muddy bottom. A lake is generally larger and has water so deep that sunlight is unable to reach it’s bottom. Plants grow on the outer edges of lakes.
Where does the Our drinking water come from? Household water • 90 percent of Americans receive drinking water from a public water supply, such as a city, town or county water department. Most of this water comes from surface-water sources like rivers, lakes or reservoirs • About 10 percent of Americans provide water for themselves, most from ground-water sources such as a well , but some from a cistern, pond or stream.
How do we use our water? Use the charts to the left to answer the following questions. 1. What is the single greatest use of water? Municipal water supply 2. How much water is used to water a golf course? 2% 3. What activity consumes the greatest amount of water in the home? The toilet 4. To conserving water would it be better to take a shower or take a bath? Take a bath
https://www.youtube.com/watch?v=zIgO8yg_u0c http://www.cbsnews.com/news/americas-dwindling-water-supply/
Water’s Journey Whether your water comes from a ground-water or surface-water source, it often travels a long distance to get to you. A watershed is the land area that surrounds or covers a water source. Rain and snow fall onto divides of basins or watershed and flow into rivers, lakes or reservoirs. Or, if there is open and undeveloped land, the water seeps through the soil and lower rock layers to replenish underground reservoirs called aquifers
Divides and Drainage Basins http://education-portal.com/academy/lesson/drainage-basins-definition-characteristics.html
What is a divide? The divide is a ridge that allows water to flow in different directions.
What is a drainage basin? A drainage basin is a an area where all of the water on one side of a divide flows off the land and drains to a specific creek, river or stream.
Runoff collects on Earth’s Surface River Basin: the term used to describe an area that drains into a large river. St. Lawrence River basin Watershed: the term used to describe an area that drains into a smaller river or stream.
Our Blue Planet is Unique Know Your Water, Conserve It Water is our most precious natural resource; we cannot live without it. While the Midwest is a water-rich region of the United States, a dependable and drinkable supply of water is becoming an increasing challenge for many municipalities, and homeowners with private wells. We are overusing ground water, and contaminating our sources. Learn about the water cycle and how to conserve water to preserve this resource for generations.
Water is a unique substance It is the only substance that exist as a solid, liquid, or gas. Liquid water can fill any container. It sustains the life of all living things. It can form into a drop of water or combine into oceans.
Question Time….. The water cycle Earth is the only planet in our solar system where water can exists as a solid, liquid or gas. Because of this unique feature, what process or activity occurs on Earth? The water cycle
How is water moved and maintained on Earth? The unending circulation of the earth’s water above and below ground is called the hydrologic or water cycle. The water present on the earth today is the same water that was formed with the planet itself. The amount of water cannot be increased or decreased.
What processes drive the Water cycle Evaporation is when water heats up and changes from liquid to vapor (Gas). Condensation is when water vapor in the atmosphere cool to become a liquid. Precipitation is when water that falls from the clouds. Examples are rain, sleet, hail, and snow.
Natural Phenomena's that effect freshwater quality Lake Turn Eutrophication
Lakes Cycle https://www.youtube.com/watch?v=X26ocQkhNH4 https://www.youtube.com/watch?v=XCh04Mi6gNo
What is lake Turnover? Lake turnover is the result of the rising and sinking of cold and warm water layers. The denser water is heavier and will be at the bottom of a lake while the less dense water is lighter and will generally be at the top of the lake. During spring and summer the sun heats the top layer of a lake which causes it to become less dense. The bottom layer of the lake does not receive sunlight and therefore remains cold. Since the top layer of the lake is less dense, it floats on top of the bottom layer and the two do not mix. In the fall and winter the sunlight is not as strong and the nights become cooler. The top layer of the lake cools off, becomes heavy and sinks. This sinking pushes nutrients and minerals up from the bottom of lake. .
The rising and falling of cold and warm pond and lake water is called turnover.
Question Time….. Why is lake turnover an important process in maintaining a health water quality? Because the freshwater in lakes are isolated and is not replaced by water from a stream, salts from the minerals that get washed into the lake will collect and not be removed. So over time the lake’s saline level could increase. The water could also become stagnant and not be aerated to where the oxygen content is reduced to the point where it will not support animal life. Lake turnover prevents these things from occurring.
Nitrogen pollution and eutrophication discovery ed
What is eutrophication? The increase of nutrients (nitrates and phosphates) in a lake or pond due to the additions of fertilizers or sewage. This causes a decrease in the oxygen level due to increase of scum or phytoplankton in the water. This eventually kills fish and other organisms.
Eutrophication
Eutrophication normally happens slowly but human activity may speed it up. The use of fertilizer, laundry detergent and other human waste contain nitrogen and phosphorus which speed up algae growth.
Water Pollution