Download Physical Oceanography Chapter 15

Hydrology Vocabulary- textbook def
recommended.. 29 terms only some in ppt.
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Down-welling
Upwelling
Monsoon
Typhoon
Tsunami
El Nino
Estuary
Transpiration
Runoff
Infiltration
Zone of Saturation
Water Table
Zone of Aeration
Permeability
Aquifer
Porosity
Subsidence
Tributary
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Floodplain
Watershed
Divide
Discharge
Eutrophication
Well
Cone of Depression
Drawdown
Recharge
Point Source Pollution
Non Point Source Pollution
Terms cont.
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Floodplain
Watershed
Divide
Discharge
Eutrophication
Well
Cone of Depression
Drawdown
Recharge
Point Source Pollution
Non Point Source Pollution
Hydrology, Rivers and Groundwater
Chapter 15, 16, -parts of 9, 10
QS: Do you KNOW ?
The Oceans of the World.. How many?
The NAMES of 8 different SEAS?
What Ocean Currents can you name?
---and their Direction N S E W?
What if you were adrift at SEA
And your plane went down.. Off the coast of NC.
QS: WHAT CURRENTS would you be in?
QS: Where would it take you?
QS: What direction do GYRES in the Northern
Hemisphere flow?
USE THE MAP ON NEXT SLIDE to Answer Each QS.
Ocean Currents – also called Gyres
ANSWERS
• Gulf Stream Current then Canary Current then North
Equatorial Current
• The Current would take you across the Atlantic Ocean
out into the Ocean away from US, and drift over to
England/ Europe.
YOU ARE IN TROUBLE if YOU ARE TO SURVIVE ..
• Gyres flow CLOCK-WISE in the Northern Hemisphere.
HOW TO SURVIVE A RIP CURRENT? Video 4 mins
https://www.youtube.com/watch?v=viKb5Ny4OWk
Water
• The oceans contain 97% of the planet’s water,
- only 3% of Earth’s water is freshwater.
• Of this freshwater, about 2.997 % is either
locked up in ice caps and glaciers or stored as
groundwater that is too deep to extract.
• Only 0.003% of Earth’s total volume of water
is available for OUR USE.. ---That is a precious
resource.. Don’t waste/pollute our water
Studying the Oceans..
• About 71% of Earth’s surface is covered by water.
• The oceans help regulate climate, provide
habitats for marine organisms, dilute and
degrade many pollutants, and help shape Earth’s
surface.
– can exist as a liquid over a wide range of temperatures
because of the hydrogen bonds between water
molecules.
– high boiling point = 100°C
– low freezing point = 0°C.
What is the Role of the OceanStudying Liquid Water
• Ocean currents are responsible for the redistribution of
energy.
-currents flow from hot to cold.. Tropics Zone to Poles
( KNOWN AS convection Gyres)
• can store a large amount of heat without a high increase in
temperature.
• protects organisms that live in water from abrupt
temperature changes, also responsible for water’s ability to
regulate Earth’s climate.
Density of Ocean Water
• Density causes ocean currents to form and
MOVE.
• Affected by temperature and salinity – we
tested in a Water Density Lab. Review..
• Salinity is how much salt/minerals are dissolved
in the water AVE Salinity in OCEAN is 35 ppt
Density of Ocean Water
• Saltwater has a higher density than
freshwater due to the dissolved salts
• Warmer water has a lower density than colder
water – increasing temp will reduce density in
water
• When water in the ocean meets, the water
with the lower density will flow above the
water with higher density
• As water travels through the water cycle, some
water will become part of The Global Conveyer Belt
and can take up to 1,000 years to complete this
global circuit. It represents in a simple way how
ocean currents carry warm surface waters from the
equator toward the poles and moderate global
climate.
TYPES of Ocean Currents and Weather
• Wind causes Surface currents to flow
• Wind is caused by the uneven heating of the
Earth’s surface
• Density Currents flow down Deep and are
driven by the water’s density
• The densest water is found in the polar regions
where colder waters are more dense.
• The water sinks down and flows toward the
equators
Ocean Currents and Weather
• Down-welling is the movement of water from the
surface to the bottom
• Upwelling is the movement from the bottom
towards the surface
• Surface currents move warmer water away from
the equators towards the poles caused by winds..
• The Gulf Stream is an example of a surface
current
• HOW ARE OCEANS EXPLORED???
• Submersibles, or underwater vessels,
investigate the deepest ocean trenches.
• Alvin Subs – carry people
• ROVs– remote operated
vehicles do not carry people.
• SCUBA equipment
• Satellites
• SONAR.
• Side-scan sonar is a
technique that directs
sound waves to the
seafloor at an angle,
so that the sides of
underwater hills and
other topographic
features can be
mapped.
• O. depth = ½ time x v
• v is constant 1482 m/s
The 5 Major Oceans- All the World’s Ocean’s are
connected so water flows freely between them.
• Pacific O. Is the Largest ocean, contains roughly half of Earth’s
seawater and is larger than all of Earth’s landmasses combined. It
has the Deepest pt. The Mariana Trench 7.2 miles deep.
• Atlantic O. -The 2nd-largest ocean, extends from Antarctica to the
arctic circle. Most explored and fished. Mid Ocean Ridge Floor..
(Titanic sank)
• The Indian O. – is 3rd -largest ocean, is located mainly in the
southern hemisphere. Fishing and 40 % of off shore Oil.
• The Southern O. – is 4th largest small at above 60 degree S. Known
for huge waves, strong winds, and frigid cold environment. Can all
freeze.
• The ARCTIC O. – the smallest Ocean, surrounds the North Pole,
frigid and cold.
World Oceans –Seas-Gulfs-Bays
Chemical Properties of Seawater
• 96.5 percent water; 3.5 percent dissolved salts.
• most abundant ions in in seawater are
Chloride and Sodium or SALT (NaCl).
Chloride is 19 ppt and Na is 10 ppt
• Most elements on Earth are present in seawater.
• Dissolved in the form of ions.
• See next slide
• Salinity - measure of the amount of
dissolved salts in seawater, expressed
as grams of salt per kilogram of water, or parts
per thousand (ppt).
• The total Salt content of seawater is on
average 35 ppt, or 3.5 %
• Seawater also contains dissolved gases and
nutrients.
http://oceanservice.noaa.gov/education/yos/resource/JetStream/ocean/dead_max.htm
The Dead SEA – highest salinity area in the World. Copy and paste link
https://www.youtube.com/watch?v=UFE4_hCe0OU
Is the Dead SEA really dead? Video watch PART 0-2:50 mins – not all.
Variations in Salinity
• may be as high as 37 ppt in subtropical regions
where rates of evaporation exceed those of
precipitation.
• 32 or 33 ppt occur in polar regions where seawater is
diluted by melting sea ice.
• The Lowest salinities often occur where large rivers
empty into the oceans. Called Estuaries..
• Seawater/SALTY is denser than Freshwater
• The density of seawater ranges from about
1.02 g/cm3 to 1.03 g/cm3 depending on its salinity
and temperature.
• SEE MAP of Ocean Salinity.. Next slide.
Seawater
Chemical Properties of Seawater
3 Ocean Layers based on Temperature
– Surface Layer – the first
layer is a relatively warm,
sunlitsome 100 m thick.
– The Thermocline is a
transitional layer which is
characterized by rapidly
decreasing temperatures
with depth.
– The bottom layer is cold
and dark with
temperatures near
freezing.
Ocean Currents
• A density current moves slowly in the deep ocean
caused by differences in the temperature and
salinity of ocean water
• Surface currents - move by wind-driven currents that
affect mainly the SURFACE and upper few hundred
meters of the ocean, can move as fast as 100 km
per day.
Surface currents follow predictable patterns
influenced by Earth’s global wind systems.
Ex: the Gulf Stream Current.
QUESTIONS to discuss about Ocean Tides and
Currents.
1. What causes currents? (deep currents and
shallow surface currents.)
2. Compare a TYPHOON and a MONSOON and
TSUNAMI.
3. Which Ocean has a diverging plate boundary or
Mid Atlantic Ridge and what does this add?
• See next slide to check..
Answers to previous slide:
1. Differences in Density of Ocean water due to
salinity and temp.
changes, also Wind Systems
caused by pressure changes.
2. TYPHOON is a hurricane occurring in region of the
Philippines or China.
MONSOON is a wind in the Indian Ocean and S.
Asia that brings heavy rains in the summer.
TSUNAMI is a very HIGH, Large Wave in the
ocean caused by earthquakes
under
the water.
3. Atlantic Ocean - it adds more NaCl or salt.. Raises
salinity.
• Ocean Currents Map… Red Warm Water, Blue Cold Water
• Note: Temperature change is greater and faster - over the land
than over the oceans. It takes water time to heat and cool.
El Nino
– El Ninõ is a “warm ocean current” that occasionally
develops off the western coast of South America that
causes many short-term climatic changes. See map
– An abnormal warming of surface ocean waters in
the eastern tropical Pacific
– During an El Ninõ, warm water from the western
Pacific O. surges eastward toward the South
American coast.
– El Ninõ brings stormy weather to areas that are
normally dry and bring drought conditions to areas
that are normally wet.
Compare El Nino – Winds during Normal Year vs El Nino
Year. In the PACIFIC Ocean. Note RED ARROW WINDS CHANGE
El Niño Conditions- Winds blow Eastward
An El Nino condition results from weakened trade winds in the
western Pacific Ocean near Indonesia, allowing piled-up warm
water to flow toward South America. East.
BAD FISHING TIME… downwelling currents and no nutrients.
Normal Conditions
• Meanwhile in the eastern Pacific along the
coast of South America an upwelling occurs.
– Upwelling is the term used to describe when
deeper colder water from the bottom of the ocean
moves up toward away from the shore. the surface
• This nutrient-rich water is responsible for supporting the
large good –fishing population commonly found in this
area.
• Good fishing time !! 
Normal Conditions- Winds blow Westward
Strong winds blow from the east along the
equator, pushing warm water into the Pacific
Ocean
Good Fishing- upwelling currents provide
nutrients.
La Nina Weather Conditions-is the positive phase of the El Niño Southern
Oscillation and is associated with cooler than average sea surface
temperatures in the central and eastern tropical Pacific Ocean.
Compared to El Niño, which is characterized by unusually warm
ocean temperatures in the Equatorial Pacific.
NEXT: Human Impact on Shorelines
• Estuaries - are where fresh water meets salt
water and are nursery areas for baby marine
life. This is important for Fish populations.
• Estuaries are affected by
– erosion by storms,
– boat wakes and tidal currents
– Pollution and temperature increases
• Long term estuaries are impacted by the rising
sea level
Impact of Development on Shorelines
• Almost half of the US population lives
near the coast
• Humans have built houses along the shore due
to recreation and other activities involving
water
• Land subsidence is when land sinks below sea
level
• Strong storms can often cause major damage as
has been seen in the past few hurricane seasons
What happens to the water once it
returns to Earth? Where does it go?
• Once water reaches Earth, it can…
– Evaporate back into the atmosphere
– Soak into the ground
– Flow down slopes on the Earth’s surface
• Runoff- water flowing down slope along the
Earth’s surface
– This water can evaporate, soak into the ground
water, or become a part of lakes and streams
Conditions for runoff
• Soils must have pores for the water to move
through.
• The pores must not already contain water
– If pores already contain water, the excess water
will either sit on top of soil or flow down slope.
• Vegetation
– Soils containing grasses allow more water to soak
into the soil. Soils without vegetation can clump
up and block pores; this does not allow the water
to enter.
• Continued.. Conditions for Runoff
• Rate of Precipitation
– Which of the following will allow more water to
enter the ground?
• A light, gentle rain or A torrential downpour
• Composition
– The presence of humus makes more soil pores
available
– Sands have large spaces between particles where
silt has almost no space between particles
• Slope
– The higher the slope, the faster the runoff and the
less water seeps into the soil
How does the water from the water
cycle become ground water?
• Infiltration- water on the surfaced passes
through the soil boundary underground
– This water moves through the empty space between
soil particles. Rain Enters the ground.. And becomes
groundwater.
• Percolation- the movement of water through soil
– This is pulled further underground by gravity
• Storage- water can be stored underground for up
to 1,400 years
• This underground water is also able to migrate
and return to oceans/ lakes
Groundwater Storage
• Water sinks into the ground by seeping into
small holes or pores between sand particles
• Porosity- percentage of pore space in a
material (open space)
• These pore spaces store large amounts of
water
The Zone of Saturation
• Zone of saturation- the depth below Earth’s
surface and water table, where all the pores
of material are filled with groundwater.
• The upper boundary of the zone of saturation
is the called the water table
Only water in zone of saturation is
considered ground water
• The zone of aeration (AIR) is the area above
the water table. Here the soil is moist, but
contains mostly air and dirt.
• Water in the zone of saturation can be classified
in two ways
– Gravitational water is water that trickles downward
as a force of gravity
– Capillary water is water that is drawn upward from
the water table and held in pore spaces
• Study pic
The Water Table
• The level of the water table varies depending
on topography and slope of the land.
– Mountainous areas have a deeper water table
than if compared to oceanic areas
• The water table also rises and falls with the
wet or dry season in an area
Groundwater Movement
• Groundwater moves downhill due to gravity
– This is slow due to the water squeezing through
tight pores in the subsurface material
• Permeability- is the ability of a material to let
water pass through it.
-Large particles are very permeable due to
the large pore spaces
– Small particles like silt have small spaces and have
a low permeability
• The movement of water varies in speed according
to the slope
• Most water movement takes place in an aquifer
• An aquifer is a permeable layer that allows
groundwater flow.
• An Aquiclude or Aquatard is Impermeable layers
or barriers that resists groundwater flow..
Find the Aquifer, and Aquitard, and
Artesian Well
Aquifers
• People use the water in aquifers for water by
building wells.
• Some are overused and the water table has
dropped lower. People then need to dig deeper
to get to the water.
• non-potable – aquifer is unsafe for drinking
happens when the area is near the coast, salt
water may intrude on the aquifer and make
the water unsafe.
• See last slide.
Aquifers
• Most land areas have an aquifer beneath
• The Ogallala Aquifer is one the largest
aquifers, it is beneath 8 US states – South
Dakota, Nebraska, Wyoming, Colorado,
Kansas, Oklahoma, New Mexico and Texas
• It is overused and is being used up before it
can be replenished which is causing conflict
among the states
Ogallala Aquifer
Subsidence
• occurs when large amounts of groundwater
have been withdrawn from certain types of
rocks. The rock compacts because the water is
partly responsible for holding the ground up.
**When the water is withdrawn, the rocks falls in
on itself.
• states like California, Texas, and Florida have
suffered damage of hundreds of millions of
dollars
Example of Subsidence
• This is a picture of the San
Joaquin Valley southwest
of Mendota in the
agricultural area of
California.
• Years and years of
pumping groundwater for
irrigation has caused the
land to drop.
• The top sign shows where
the land surface was back
in 1925! Compare that to
where the man is standing
(about 1977).
WATERSHEDS & Stream Systems
• Precipitation that does not enter the ground
water runs off.
• This water carves out channels called streams.
– Smaller bodies like brooks and creeks flow into
streams and rivers.
– Large streams are referred to as rivers
• These streams enter into larger bodies of water.
• A series of streams that flow together to create a
larger body of water is referred to as a tributary
WATERSHEDS
River Systems and Basins
• A collection of tributaries and rivers that flow
together and empty into the ocean or sea
River System
• River source or headwaters are the beginning
of a river – often in mountains – may be fed by
springs, or runoff from rain, snow etc.
• A tributary is a small stream or river that
flows into the main river
• Floodplain is relatively flat land area on both
sides of a river that may flood during heavy
rain or snow
• A meander is a loop in the course of a river, it winds
back and forth instead of straight
• The mouth is where the river flows into a larger body
of water such as another river, ocean, lake etc.
• Discharge is the measure of a volume of stream water
that flows over a specific location in a particular
amount of time. This amount of flow or discharge
increases a streams carrying capacity.
The NC River Basins near you are the
Catawba River Basin and the
Yadkin Pee Dee River Basin..
River Basins
• There are 17 river basins in NC
• The Cape Fear is the largest, Savannah the
smallest
• A River Basin is all the water – tributaries,
lakes, reservoirs, groundwater etc. that flows
down toward the river
• Watersheds are smaller land areas that are
part of a river basin
Watersheds and Divides
• Watershed- all of the land area whose water
drains into a stream system (drainage basin)
– These can be small or large in size
• Divide- a high land area that separates two or
more watersheds.
Every tributary has its own watershed and divide,
but they are part of the larger stream system
https://www.youtube.com/watch?v=f63pwrMXkV4
VIDEO: WHAT IS A WATERSHED? 3 MINS
Mississippi Watershed – see all the land
and streams that drain into the stream.
“Divides” are at the High Elevation
“BASINS” are low elevation areas
Implications of Running out of
Freshwater Resources
• Freshwater resources are not distributed evenly
– the US has plenty of freshwater, much of it is in the
eastern states.
– Some has been contaminated by agricultural or
industrial processes.
– Worldwide water distribution is a problem,
– About 25 countries, primarily in Africa, experience
chronic water shortages
• The current rate of withdrawal worldwide is
five times greater than it was just 50 years
ago.
– About 41% of the water withdrawn each year is
used to irrigate
– About 38% of freshwater is used for cooling
purposes in power plants, for oil and gas
production, and in industrial processing.
– About 10% goes to domestic and municipal uses.
– See next slide
Human Impact on Water Resources
• Freshwater is Earth’s most
precious natural resource.
• Human demands for
freshwater include
household use,
agriculture, and industry.
• #1 Water Use in USA
is Agriculture..
Aqueducts
• Used to bring water from areas where it is
plentiful to areas in need .
• The California Water Project transports water
from northern to southern California.
• Conflicts over the transport of surface water
will probably increase as human populations
create higher demands for water.
Freshwater Supplies
• The best way to meet the need for freshwater is to
use available supplies more efficiently.
• Farmers can prevent evaporation of irrigation
water by using irrigation methods such as trickle
irrigation.
• Industries can use recycled water instead of clean
freshwater for manufacturing processes.
• Many domestic uses can be reduced by installing
low-flow toilets, using plants that are droughtresistant for landscaping, and fixing leaky pipes and
faucets. Call 311 for city water issues and leaks.
Lakes
• Lake- a depression in the surface of materials of
a landscape that collects and hold water
• Lakes receive water from streams, run off, and
local precipitation
• Most lakes have outlets from which water flows
into rivers and oceans
• Small man-made lakes are referred to as ponds
• Lakes that store water for the use of community
are called reservoirs
Eutrophication
• Eutrophication is the process by which lakes
become rich in nutrients from the surrounding
watershed
– This results in a change of the kinds of organisms that
live in the lake
• This happens naturally, but can be sped up by the
addition of nutrients
– Fertilizer ,etc.
• Sources of nutrients include animal wastes and
phosphate detergents.
EUTROPHICATION INFO AND VIDEO LINK.. Play and check it out.
http://study.com/academy/lesson/human-causes-ofeutrophication.html watch length 0- 3: 40 sec..
Steps of Eutrophication and the Result
• A lake is formed either from blocking a stream or
the dissolving of calcium carbonate to form
underground caverns
• Nutrients are added to the water by natural means
or by fertilizers and animal waste.
• The nutrients cause algae to grow
• Algae uses the oxygen in the water
• The oxygen deprivation kills other organisms
• End RESULT: The organisms like fish then die and
decay- can lead to DEATH OF ALL LIFE IN THE
LAKE.
What are Wetlands?
• They are Land areas that are covered with
water for part of the year.
– SUCH as: bogs, marshes, and swamps.
• Play a large Role- in water quality because
they Serve as a filtering cleaning system for
area waters.
• Different wetlands have different soil types
and support different species
Bogs
• Bogs are not stream fed, they receive water
from precipitation.
• Waterlogged soil is home to peat moss
– The peat moss makes the soil very acidic
• The acidity of the soil allows for unusual
plants to grow
– This includes insect-eating plants like pitcher
plants, sundew, and Venus’ flytrap.
Freshwater Marshes
• Form in areas around the mouths of streams
and deltas.
• The constant flow of water allows for marsh
grass to grow
Swamps
• Often low-lying areas near streams
• Can form from marshes that have filled in to
support shrubs and trees
• This coverage from the larger plants kills the
marsh grass that begins to decay.
• Over time, swamps become coal deposits.
Earthcache Bog in Massachusetts
Marsh in Charleston
Atchafalaya Swamp is the largest
in North America
Why Wetlands are GOOD.
• filter and Clean water by trapping pollutants,
sediments, and bacteria
• Provide homes for animal species including
migratory birds.
• People used to fill wetlands to build on the
land, but now there is a global effort to
preserve them
Springs
• Water will discharge at the Earth’s surface
where an aquifer and an aquiclude come into
contact. These natural discharges of water are
called springs.
Hot Springs
• Hot springs- springs that have temperatures
higher than the human body
• There are thousands of hot springs in the US.
• Most are found in the western states due to
igneous activity in the past.
• Explosive hot springs that erupt at regular
intervals are called geysers
Wells
• Wells are deep holes that are dug or drilled into
the ground to reach a reservoir of groundwater.
• to dig a well is to dig below the water table into
the zone of saturation
• If someone over pumps their well, it can lower the
water table causing a cone of depression
• see next slide.
• The difference between the original level and the
water level in a pumped well is called the
drawdown.
• Eventually, the cone of depressions of
several wells may overlap. This lowers the
water table and dries up shallow wells.
• RECHARGE is WHEN Water is added to the
zone of saturation from precipitation and
runoff .
– This replenishes the wells that have gone dry if
the recharge is more than the withdrawal. If
not, all the wells will go dry.
Note ALL PARTS ON the pic – ESP CONE OF DEPRESSION WHICH
IS A SINK IN THE GROUND DUE TO WATER BEING USED.
Confined Aquifers
• Confined aquifers are found deep underground
and often under aquicludes.
– This makes them hard to pollute
• Aquifers that build up pressure from being held
between two aquicludes are called artesian
aquifers.
• If a well is dug in this area, the pressurized water
can spurt above the ground like a fountain. This
is an artesian well.
– Springs from pressured water are artesian springs
Threats to Our Fresh Water Supply
• Overuse- water in an area is being pumped out
more than it is being recharged causing a drop in
the water table.
• Subsidence- the ground above an aquifer sinks and
squeezes together the pores of the aquifer
• Pollution in Groundwater- pollutants from septic
tanks or landfills enter the ground above the water
table and are flushed down by precipitation. Once
it contacts the water table, it easily spreads
contaminating the water.
• Chemicals- chemicals like arsenic react with
water and pollute aquifers, because they
cannot easily be removed.
• Salt- over-pumping of wells in coastal regions
causes underlying saltwater to rise into wells
and contaminate freshwater aquifers
• Radon- Radon is an element formed from
radioactive Uranium. This is a gas that seeps
into groundwater in some areas and
contaminates the groundwater. Radon gas is
one of the leading causes of cancer in the US.
Water Pollution
Humans depend on very small reservoirs of water
for all our needs
These reservoirs cycle/ turnover very quickly.
As they cycle they can either:
1. collect pollution from other sources
or
2. be cleaned by passing through
functioning
ecosystems
https://www.youtube.com/watch?v=xZ773hCN2sU
Make sure you watch Video and do Questions 1-8 ON WEBPAGE
– THE GREAT PACIFIC GARBAGE PATCH. LOOK UP ONLINE AS NEEDED
AND ATTACH TO THIS STUDY PACKET.
Water Pollution
Two major classifications
•Point
Source
•Non-point
Source
Water Pollution – Identify areas of
Nonpoint and Point Source Pollution in pic
What is Point Source POLLUTION?
• Pollution that Comes from a Single large
source.
• Can see it as coming from one spot location.
– EXAMPLES: Industrial Plants and Sewage pipes.
Point source pollution
Example pics
– one spot
• What is Non-point Sources of Pollution? :
• It is a type of pollution that Diffuses or comes from MANY Smaller
point sources – not just one place.
• EXAMPLES:
Cars and Trucks, Fertilizer on fields, Industrial plants,
Video Clip 3mins What is NON POINT SOURCE POLLUTION?
https://www.youtube.com/watch?v=phmN-IpR3xw
• Try the Kahoot Review on my Webpage.
Non point source
Pollution.
Comes from
Many places..
Example pics-