Chapter 9 Flashcards
where is the most of the world’s freshwater found
glaciers
which nation uses the most amount of water per day
the US
what percent of water covers Earth’s surface
70%
what percent of water on Earth is saltwarer
97%
examples of surface water
ponds, lakes, streams, rivers, oceans
what are the 2 types of water sources
groundwater and surface water
which water source provides the most water
groundwater
what are the 3 problems associated with groundwater extractions
- sinkholes
- saltwater intrusion
- depletion
what percentage of the US irrigation is microirrigation
3%
is Earth’s freshwater even distributed
nope
T/F: water shrinks when it freezes
false it expands
T/F: waters’ specific heat is higher than most other liquids
true, its’ higher than any other liquid except ammonia
T/F: water is not a good solvent
false, it is actually better than any other common liquid, which is why it can dissolve lots of different substances and explains how water can become polluted so easily
what causes the unusual properties of water
the bipolar distribution of the electric charge on the neutral molecule contribute to its peculiar properties
T/F: All of Earth’s water is directly useful
false because it is either salty or inaccessible
what powers the hydrological cycle
solar power
what are the 2 main processes in the hydrological cycle
- evapotranspiration
- precipitation
what is evapotranspiration
the transfer of water into the atmosphere via evaporation and transpiration
What speed does water move through the hydrological cycle
water moves are various speeds
(40k years to recycle seawater, 2 weeks for river water, 9-10 days for atmospheric water)
What is the difference between withdrawn water and consumed water
withdrawn water is water that is taken, used, and maybe returns to its original source, whereas consumed water is a type of withdrawn water that may not be returned to its original source
an example of withdrawn water
a power plant borrowing water from a nearby river to cool generators, then returning that water back to the river
which sector is the greatest for withdrawing water
industry
which sector is the greatest for consuming water
agriculture
what are deficit areas
Deficit areas receive less precipitation
than is needed by established vegetation and organisms
what are surplus areas
surplus areas receive more precipitation
than is needed by established vegetation and organisms
T/F: surface waters include flowing and basinal waters
true: flowing waters - streams, rivers
basinal waters - ponds, and lakes
what is discharge
the volume of water carried in a stream channel
what is the relationship between discharge and channel sizes
discharge increases with the size of the channel
what led to the passage of Clean Water Act of 1970s
pollution
where is the majority of accessible freshwater located?
groundwater (water beneath the Earth’s surface)
what forms the water table
the precipitation infiltrating through the soil and rock to become groundwater
what is an aquifer
an area with permeable rock, like sandstone or gravel, containing the zone of saturation
what is another name for the unsaturated zone
vadose zone or zone of aeration
what is another name for the saturated zone
phreatic zone
where is groundwater
in the saturated zone
where is subsurface water
unsaturated and saturated zone (aka the unconfined aquifer)
what is an aquitard
an impermeable layer that halts water infiltration
what is recharge
water moving into an aquifer
what controls the behavior of groundwater
geology and geometry of rocks & sediments
what is an unconfined aquifer
an aquifer without an aquitard above it
what is a confined aquifer
an aquifer with an aquitard above and below
when does an artesian system form
when the hydrostatic water pressure increases in a confined aquifer
what is the height that water rises to in an artesian system called
the potentiometric surface
the fountain like squirt from the artesian system is called
the artesian well
what is the potential energy in an aquifer
hydraulic head
what reflects the hydraulic head in an unconfined aquifer
the height of the water
what is the relationship between the water table and the hydraulic head
the higher the water table, the higher the head
what is the relationship between the potentiometric surface and the hydraulic head
the higher the potentiometric surface in a confined aquifer, the higher the hydraulic head
which way does groundwater flow in relation to hydraulic heads
flow from areas of high hydraulic head to areas with low hydraulic head
what are the 2 kinds of problems that reduce groundwater’s utility
- discharge problems
- withdrawal problems
what can discharge problems lead to
groundwater pollution
what is the issue with groundwater pollution
metals, organics, and toxins trapped in groundwater are long-term problems
what are the 3 problems withdrawal can lead to
- depletion
- land subsidence
- saltwater intrusion
what is considered to be the greatest water pollution problem for the future
groundwater pollution
what causes withdrawal problems
the removal of groundwater from aquifers
what is depletion in the sense of withdrawal problems
water is removed faster than it can be replenished
what is land subsidence in the sense of withdrawal problems
sink holes occur where the groundwater table falls
what are the “kidneys” of the hydrological cycle and why are they considered to be the “kidneys”
wetlands are considered to be the “kidneys” because they are major recharge areas as they retain water for long period of time, purifying it and allowing it to infiltrate the aquifer
where are recharge times the longest
in areas with lower rainfall, like deserts
what is groundwater in desert-like areas called and why?
“fossil water” because the water was deposited there many years ago when the climate was wetter in that area and due to its age the water quality is poor and is likely highly saline
what is saltwater intrusion
salt water normally at the bottom of groundwater is brought up through freshwater layer if it is pumped too fast
what can cause a cone of depression
overpumping
what is a cone of depression
the localized lowering of the water table around a well from which water is being withdrawn faster than it is replenished
T/F: land subsidence is more localized than aquifer depletion
true
what is a type of land subsidence
sink holes
what is it to be considered “water scarce”
to be a nation with less than 1000 cubic meters of water supplies per person per year
what is it to be considered “water stressed”
to be a nation with 1000 - 1700 cubic meters of water supplies per person per year
3 solutions to address the water shortages
- increasing efficiency of use
- recycling by reusing wastewater
- substitution by using salt water
(4. increasing water resources)
how can we increase efficiency of the use of water
microirrigation (transporting water to crops via pipes)
T/F: microirrigation can save 300% of water previously used
true!!
how we reuse wastewater
improving technology and consume education
how can we start using salt water
process like desalination can remove salt particles from salt water making it into freshwater
how do we increase our water resources
shifting water from one region to another via dams and reservoirs or canals and pipelines
why isn’t increasing our water resources the best idea
- when building dams and reservoirs environmental impacts must be considered
- building canals and pipelines can lead to litigation in areas like CA or habitat destruction and pollution as seen in FL
how to help with the water shortage at home
- microirrigation for agriculture -> drip systems for home gardening
- individual lifestyle conservation
-> shorter showers
-> low-fish toilets - wastewater reclamation
-> closed loop reclamation
-> graywater use
why should we consider wastewater reclamation
- wastewater can be safe to drink if treated properly
- graywater can be used for water needs other than drinking
- it is cheaper to treat wastewater than to desalinate salt water
2 ways to desalinate water
- membrane (reverse osmosis)
- distillation methods
what is the membrane method
when you pass the salt water through a membrane at high pressures and salt particles shouldn’t be able to pass through the membrane
what is the distillation method
heat the saltwater to cause the evaporation of the water and leaves behind its salt particles
downside of dams
- sediment accumulation
- downstream scouring
- water loss from evaporation
- salination from evaporation
- dam break could lead to catastrophes
- biological disturbances
- social disturbances
legal solutions to surface water use
- Riparian water law
- Appropriation water law
what does the Riparian water law do
dictates that all landowners adjacent to the land, such as from a river or a bank, then they can withdraw that water (and is mainly practiced east of the Mississippi River)
what does the appropriation water law state
“first in time, first in line” and is applied west of the Mississippi river
why don’t farmers conserve water during irrigation
the government heavily subsidizes the cost of water
why to coastal climates have less extreme temperature variations than other non-costal climates
since water’s specific heat is high, it makes it so water takes a long time to absorb and release the heat making the temperature NOT vary as much in coastal climates since they are around large bodies of water
how much of Earth’s freshwater is readily available in the liquid state
0.6%
what are effluent charges
the cost of disposing industrial wastewater
why is it more difficult to monitor groundwater
because groundwater moves much more slowly therefore making depletion and pollution take years to detect and remedy
which is easier to regulate: groundwater depletion or groundwater pollution
groundwater depletion is easier to regulate
when is it better to use economic solutions
when there are a lot of parties involved
when is it better to use legal solutions
when there is a small number of parties that use that resource
