Our Dynamic EarthDynamic Earth

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The Hydrosphere
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Hydrosphere

• The hydrosphere includes all of the water on or
  near the Earths surface.
• This includes water in the oceans, lakes, rivers,
  wetlands, polar ice caps, soil, rock layers
  beneath Earths surface, and clouds.

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The Water Cycle

• The water cycle is the continuous movement of
  water from the ocean to the atmosphere to the
  land and back to the ocean.

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Earths Oceans

• All of the oceans are joined in a single large
  interconnected body of water called the world
  ocean. The world ocean play important roles in
  the regulation of the planets environment.

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Earths Ocean Basins

• Pacific largest and deepest ocean single
  largest geographic feature on Earth
• Atlantic half the size of the Pacific
• Indian smaller than the Atlantic but has the
  same average depth
• Arctic 7 the size of the pacific and ¼ as deep
  as the other oceans

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Ocean Water

• The difference between ocean water and fresh
  water is that ocean water contains more salts.
• Salinity is a measure of the amount of dissolved
  salts in a given amount of liquid.
• The salinity can vary depending upon the amount
  of rain, temperature, and freshwater that flows
  into the ocean.
• Deep water has a higher salinity because it is
  colder.

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Global Temperature Regulator

• One of the most important functions of the world
  ocean is to absorb and store energy from sunlight
  which in turn regulates temperatures in Earths
  atmosphere.
• If the ocean did not regulate atmospheric and
  surface temperatures, temperatures would be too
  extreme for life to exist on Earth.

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El Nino and La Nina

• El Nino- an episode-occurring every 3 to 7 years-
  of ocean warming that affects the eastern
  tropical Pacific warm counter currents become
  usually strong and replace normally cold off
  shore waters with warm equatorial waters. Marked
  by abnormal weather patterns in Equador and Peru.
  
• La Nina- surface conditions in eastern Pacific
  are colder than average can increase hurricane
  activity.

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Freshwater

• Fresh water is water that contains insignificant
  amounts of salts. It makes up 3 of the Earths
  water supply.
• Most of the fresh water is locked up in icecaps
  and glaciers while the rest is found in places
  like lakes, rivers, wetlands, the soil and
  atmosphere.
• A river system is a network of streams that
  drains an area of land and contains all of the
  land drained by a river including the main river
  and all its smaller streams or rivers that flow
  into larger ones, or tributaries.

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Tributary- a stream that empties into another
stream
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Running Water

• Streams are most important agents of erosion
• The ability of a stream to erode and transport
  depends on its velocity.

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Running Water

• Factors that determine velocity
• Gradient - the slope or steepness of a stream
  channel. The steeper the gradient, the more
  energy the stream has as it flows downhill.
• Channel characteristic - the course the water in
  a stream follows. As the water flows, it
  encounters friction from the sides and the
  bottom. The amount of friction is affected by
  the shape, size, and roughness of the channel.
• Discharge - the volume of water flowing past a
  certain point in a given unit of time.

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Meandering
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River Basin

• A large area that drains to the ocean
• Ex. Catawba River Basin
• Water Shed- a smaller area that drains to a
  certain area.
• Aquifer- An underground (groundwater) water
  source that we use
• Water quality of NC chemical, physical and biotic
  index

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Groundwater

• Rain and melting snow sink into the ground and
  run off the land. Most of this water trickles
  down through the ground and collects as
  groundwater.
• Although it makes up only 1 percent of all the
  water on Earth, groundwater fulfills the human
  need for fresh drinking water, and supplies
  agricultural and industrial need.

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Human Impact on the Hydrosphere
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Water Pollution
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Water Pollution
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Clean Water A Life Sustaining Liquid

• Remember that freshwater makes up a very small
  fraction of all water available on Earth.

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Where does water pollution come from?

• Sources of Point Pollution
• 23 million septic-tank systems
• 190,000 storage lagoons for polluted waste
• 9,000 municipal landfills
• About 2 million underground storage tanks
  containing pollutants such as gasoline
• Thousands of public and industrial wastewater
  treatment plants

• Sources of Nonpoint Pollution
• Highway construction and maintenance eroding soil
  and toxic chemicals
• Storm-water runoff from city or suburban streets
  oil, gasoline. Dog feces, litter
• Pesticides from 112 million hectares of cropland
  treated with these substances each year.
• 50 million tons of fertilizer applied to lawns
  and crops
• 10 million tons of dry salt applied to highways
  for snow and ice

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Marine Water Pollution
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Where does pollution come from in our oceans?
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Wells

• Wells are dug or drilled to tap into underground
  water. With a dug well it is hard to prevent
  contamination of the water.
• Drilled wells are made into underground aquifers.
  These are lined, sealed, and do a much better
  job of keeping out microorganisms and chemicals.

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Problems with Wells

• Contamination by microorganisms or by chemicals.
• Soil salination as the water table drops, the
  salt in the soil dries out which can cause a
  problem for nearby vegetation.

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Aquifer Depletion

• Salt water intrusion-occurs when salt water moves
  in where fresh water should be located.
• Subsidence- When the land level falls due to loss
  of groundwater.

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Dams and Dam Removal

• Dams are used to provide drinking water, water
  for agriculture, generate hydroelectric power,
  and recreational opportunities.
• Dams can also cause problems
• Flooding of natural habitats upstream
• Fragmentation of migratory fish population
• Sedimentation behind dam can cause there to be
  less water available for hydroelectric power
• reservoir is a breeding ground for disease
  causing insects like mosquitoes.
• Disrupts the natural flow of streams and rivers.

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Dam Removal

• Dam removal benefits
• Avoid catastrophic dam failure
• Benefit aquatic life and migratory fish
• Restore downstream habitats
• Restore the natural flow of streams and rivers

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Importance of Water Conservation

• Goals of water conservation
• Sustainability withdrawal of water should not
  exceed its natural replacement rate
• Energy conservation pumping and treating water
  takes a lot of energy
• Habitat conservation
• Reduce water consumption per capita use water
  more efficiently and responsibly.