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Earth/environmental Science Mrs. Schneider

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1 Earth/environmental Science Mrs. Schneider
Unit 2 – The Hydrosphere Earth/environmental Science Mrs. Schneider

2 Unit 2 Vocabulary Water cycle River basin Evaporation Aquifer
Transpiration Precipitation Condensation Infiltration Sublimation Permeability Impermeable Runoff River basin Aquifer Watershed Eutrophication Subsidence Point source pollution Non point source Well Artesian well Wetland

3 Vocabulary Chapters: 9, 10, 14, 28.3 Zone of aeration Groundwater
Water table Zone of saturation Groundwater recharge Chapters: 9, 10, 14, 28.3

4 The Hydrosphere

5 The Water Cycle The water cycle is made up of four main parts:
Evaporation and Transpiration Condensation Precipitation Accumulation

6 Evaporation and Transpiration
Evaporation is when the heat from the sun warms up water and turns it into water vapor OR the change of liquid water into gaseous water. Transpiration is when water evaporates from plants helping to keep them cool. The rate at which water will evaporate or transpire from plants depends on the temperature, wind, and humidity.

7 Condensation Water vapor condenses in the atmosphere to form clouds. As clouds form, they move because of wind. When the clouds can’t hold all the moisture that has made them, they release the water in the form of precipitation.

8 Precipitation The main forms of precipitation are rain, hail, snow, sleet, and freezing rain. Precipitation brings the water back to the ground.

9 Accumulation Accumulation of the precipitation is the final stage of the water cycle before it starts all over again. Subsurface accumulation - soaking into the earth and become ground water that plants and animals use Surface accumulation - runoff from hills and mountains accumulates back into lakes, rivers, and oceans.

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11 Surface water movement
Through precipitation, water returns to the Earth’s surface and can either: Evaporate back into the atmosphere Soak into the ground Flow downslope becoming runoff.

12 Surface or Groundwater?
What affects the rate of water infiltration underground? Precipitation: The greatest factor controlling infiltration is the amount and characteristics (intensity, duration, etc.) of precipitation. Soil characteristics: particle size of the soil determines its ability to absorb water. (Sand, Silt, Clay) Soils, such as clay, absorb less water at a slower rate than sandy soils. This results in more runoff into streams.

13 Surface or Groundwater?
What affects the rate of water infiltration underground? Soil saturation: Like a wet sponge, soil already saturated from previous rainfall can't absorb much more ... thus more rainfall will become surface runoff. Slope of the land: Water falling on steeply-sloped land runs off more quickly and infiltrates less than water falling on flat land.

14 Surface or Groundwater?
What affects the rate of water infiltration underground? Land cover: Land cover has a great impact on infiltration and rainfall runoff. Vegetation can slow the movement of runoff, allowing more time for it to seep into the ground.

15 River basin vs. watershed
An area of land that drains all streams and rainfall to a common outlet (marsh, stream, river, lake, groundwater) In a river basin, all the water drains to a large river. The term watershed is used to describe a smaller area of land that drains to a smaller stream, lake or wetland. There are many smaller watersheds within a river basin.

16 Importance of watersheds and river basins
Watershed consists of surface water--lakes, streams, reservoirs, and wetlands--and all the underlying ground water. Watersheds are important because the stream flow and water quality of a river are affected by everything happening in the surrounding land area. Everything we do affects our watershed – from washing clothes and growing food to mining and farming. The reverse is also true: our watershed affects everything we do, by determining what kinds of plants we can grow, the number and kinds of animals that live there, and how many people and livestock can be sustainably supported by the land.

17 NC River Basins There are 17 river basins in North Carolina
5 western basins drain to the Gulf of Mexico 12 drain to the Atlantic Ocean Only 4 are entirely contained in NC

18 Aquifer The area underground permeable layers where most groundwater flow takes place. Impermeable layers, called aquicludes, are barriers to groundwater flow.

19 Confined Aquifers Water-table aquifers are unconfined and unprotected, and easily polluted. The aquicludes form barriers that prevent pollutants from reaching aquifers surrounded by aquicludes.

20 The Zone of Saturation The Water Table
Depth varies depending on local conditions. Topography follows the topography of the land above it. Fluctuates with seasonal and other weather conditions. Gravitational water is water that trickles downward as a result of the force of gravity. Capillary water is water that is drawn upward from the water table.

21 Groundwater Erosion and Deposition
Most groundwater contains some acid, in most cases carbonic acid. Groundwater is usually slightly acidic and attacks carbonate rocks, especially limestone – which plays a major role in the formation of limestone caves. Caves Practically all caves of significant size are formed when groundwater dissolves limestone. Most caves develop in the zone of saturation just below the water table.

22 Wells Wells are holes dug or drilled deep into the ground to reach a reservoir of groundwater. Overpumping of the well lowers the water level in it and produces a cone of depression in the water table around the well.

23 Artesian Wells An artesian spring is a spring that discharges pressurized water. An important artesian aquifer in the United States is the Ogallala Aquifer, which is located in the Great Plains.

24 Origin of the Oceans Where did the water come from?
Earth’s first oceans likely formed more than 4 billion years ago. Where did the water come from? Some water may have come from impacting comets or from deep within Earth’s interior. Scientists theorize that water from within Earth’s interior was released by volcanism.

25 Distribution of Earth’s Water
The Blue Planet Approximately 71 percent of Earth’s surface is covered by oceans. The oceans contain 97 percent of the water found on Earth. Major Oceans The major oceans are the Pacific, Atlantic, Indian, Arctic, and Antarctic.

26 Distribution of Earth’s Water
Major Oceans

27 Physical Properties of Seawater
Seawater is a solution of about 96.5 percent water and 3.5 percent dissolved salts. The most abundant salt in seawater is sodium chloride (NaCl). Most elements on Earth are present in seawater. Ocean surface temperatures range from –2°C in polar waters to 30°C in equatorial waters. Seawater density changes with changes in salinity and temperature.

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29 Ocean Layering Ocean water temperatures decrease with depth. The ocean can be divided into three layers: the surface layer, the transitional thermocline, and the bottom layer. In general, ocean layering is caused by density differences in water temperature and salinity. Both the thermocline and the warm surface layer are absent in polar seas, where water temperatures are cold from top to bottom.

30 Ocean Layering

31 Sea Level Change (over 4Billion year history of earth)
Main reasons for change in sea level over time: Tectonic plates moving over long periods of time; Rising air temperatures causing ocean water to expand and take up more room; Melting ice caps and glaciers. Not a uniform process: Dependent on winds, ocean currents, etc. Impacts vary widely by region.

32 Sea level change Pictures of coastal cities
Graphs showing sea level change

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34 Threats to Our Water Supply
Freshwater is Earth’s most precious natural resource. Human demands for freshwater include household use, agriculture, and industry. Overuse If groundwater is pumped out at a rate greater than the recharge rate, the groundwater supply will decrease.

35 Threats to Our Water Supply
Pollution in Groundwater

36 Protecting Our Water Supply
There are a number of ways in which groundwater resources can be protected and restored. All major pollution sources need to be identified and eliminated.

37 Point Source Pollution
From a single source. Examples include: Bacteria and viruses entering water supply system through the dumping of sewage or toxic waste. Industries using stream water and returning it polluted.

38 Non point source pollution
Water pollution from widely spread areas. Caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters and ground waters.

39 Non point source examples:
Excess fertilizers, herbicides and insecticides from agricultural lands and residential areas Oil, grease and toxic chemicals from urban runoff and energy production Sediment from improperly managed construction sites, crop and forest lands, and eroding streambanks Salt from irrigation practices and acid drainage from abandoned mines Bacteria and nutrients from livestock, pet wastes and faulty septic systems Atmospheric deposition and hydromodification

40 Impact of Non point source
States report that nonpoint source pollution is the leading remaining cause of water quality problems. The effects of nonpoint source pollutants on specific waters vary and may not always be fully assessed. We know that these pollutants have harmful effects on drinking water supplies, recreation, fisheries and wildlife.

41 Wetlands and Estuaries
What is a wetland? lands where saturation with water is the dominant factor determining the nature of soil development and the types of plant and animal communities living in the soil and on its surface What is an estuary? A partially enclosed body of water formed when freshwater (streams, groundwater, etc.) empties into the ocean

42 Wetlands and Estuaries
Why are they important? Wetlands perform valuable functions including: water quality and flood protection act as filters, removing pollution from runoff plants and soils also act as a natural buffer between the land and the ocean prevent erosion and stabilize the shoreline. Estuaries are critical to the survival of tens of thousands of birds, mammals, fish, and other wildlife. serve as nursery grounds for two-thirds of the nation's commercial fish and shellfish

43 Wetlands and Estuaries
What is happening to them? agriculture pesticide runoff commercial and residential development road construction resource extraction

44 Wetlands and Estuaries
Why is it important to us? “ecosystem services” Bees and other insects pollinate many of the crops we eat. Birds and bats eat insect pests that threaten the crops. Forests supply wood for our houses. Many people eat wild plants, fish and game. Our drinking water is purified by forests and wetlands. Bacteria break down our wastes. Plants, bacteria and fungi help to cure disease and maintain health.

45 Measuring Water Quality
Monitor the organisms found in the water. Certain things, like mayfly, can not tolerate pollution. Leeches can survive more polluted water. Measure amount of dissolved oxygen (DO). The greater the amount of DO the better environment for life. Minimum to support large fish population 4-5 ppm, need 9 ppm+ for good fishing waters. Measure the turbidity – the measure of water clarity – describes the cloudiness of water. When measured in mg/L the smaller the number the better quality water.

46 Wastewater treatment What is it? Where does the water come from?
cleaning used water and sewage so it can be returned safely to our environment. Where does the water come from? Homes Industries, schools, businesses Storm water infiltration and from runoff and groundwater

47 Wastewater treatment What do the treatment plants do?
Remove solids--everything from rags and plastics to sand and smaller particles found in wastewater; Reduce organic matter and pollutants--naturally occurring helpful bacteria and other microorganisms consume organic matter in wastewater and are then separated from the water; Restore oxygen--the treatment process ensures that the water put back into our rivers or lakes has enough oxygen to support life.  

48 How does it work? Step 1 Preliminary and Primary treatment, which removes 40-60% of the solids

49 How does it work? Step 2 Secondary treatment, which removes about 90% of the pollutants and completes the process for the liquid portion of the separated wastewater.

50 How does it work? Step 3 Sludge (biosolids) treatment and disposal.

51 What happens to the treated water?
Many processes in a wastewater treatment plant are designed to mimic the natural treatment processes that occur in the environment, whether that environment is a natural water body or the ground. Once the water has passed through the treatment process it is pumped to some kind of release area – a wetland, stream, fields, etc. to finish the cleaning process and return it back to the environment.

52 Study Guide Terms: Look over all vocabulary, salt water intrusion, What are the 3 things that can happen to precipitation on the ground? Be able to explain why and how ocean currents occur. Review the ocean currents coloring sheet. Ocean layering around the earth. Main causes of sea level change over time. Methods of shoreline stabilization. NC River Basins information

53 Study Guide Be able to explain –
Why rainwater is a nonpoint source pollutant. How do people contribute to the destruction of wetlands? All of the factors (5) affecting water infiltration and how they do. Common groundwater pollution sources and how they enter the aquifers. What the water table is and how/why it varies. What is the purpose of waste water treatment?


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