The Water Cycle
By: Jason Joo, Priyanka Solanky, and Mason Hohil
Condensation
Solar
Energy
Precipitation
Transpiration
Evaporation
Evaporation
Run- Run
off -off
Collection
Eutrophication
Land
Water
The Global Water Cycle
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Solar energy drives the water cycle
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It evaporates water, then later the water falls back to the ground due to gravity
Precipitation, evaporation, as well as transpiration from plants,
continuously move water between the land, oceans, and the atmosphere
Evaporation
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Evaporation is the process through which water transforms into gas/water
vapor and goes up into the atmosphere.
Evaporation requires some sort of energy to occur, such as heat.
The heat breaks the hydrogen bonds that hold individual water molecules
together.
Nearly 90% of the atmosphere’s moisture comes from the evaporation of
oceans, lakes, rivers, and other bodies of water.
Transpiration
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Transpiration is the process by which moisture is carried through plants
from roots to small pores on the underside of leaves, where it changes to
vapor and is released to the atmosphere.
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Transpiration is basically evaporation of water from plants.
10 percent of Earth’s atmosphere's moisture is transpired by plants.
Condensation
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The process in which water vapor in the atmosphere turns into liquid water
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Forms clouds and is the opposite of evaporation
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All air has some water in it, and clouds
form when air rises and condenses
Precipitation
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Transports water from the atmosphere to the surface of the earth
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Rain, snow, sleet, or hail that falls to the ground
Excess precipitation forms systems of surface water and groundwater, all
of which flow back to the sea, completing the water cycle
Acid Precipitation
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Acid precipitation occurs when water contains a dangerous amount of
nitric or sulfuric acids.
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Can occur because of air pollutants
It evaporates, goes into the atmosphere, reacts with water and oxygen
there, and falls as rain, snow, sleet, etc.
This acid rain is detrimental to animals and
other living organisms in ecosystems.
Run-off
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Excess precipitation that was not absorbed into the soil
Goes from ground surface to a place where water collects
Eutrophication
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A body of water gets filled with a high amount of nutrients like phosphates
and nitrates.
These nutrients promote an excessive growth of algae
When the algae dies and decomposes, the water is depleted of its
available oxygen due to excessive decomposing organisms and organic
matter
The lack of oxygen kills other organisms, like fish
Eutrophication is a natural slow-aging process for a body of water, but
human interaction can dramatically speed it up
Collection
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When water falls as precipitation, it either collects in bodies of water or will
soak into the ground and collect as underground water.
When the precipitation falls into bodies of water, the water will join the
lakes, rivers, oceans, etc.
Human Effects
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One of the main sources of water vapor is transpiration from the dense
vegetation in tropical rain forests.
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The destruction of these forests changes the amount of water vapor in the air
May alter local and global weather patterns
Pumping large amounts of groundwater to the surface for irrigation affects
the water cycle
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Can increase the rate of evaporation over land and may deplete groundwater supplies
Human Effects (cont.)
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As the human population grows and the natural landscape is replaced by
man-made surfaces (ex. roads, houses, parking lots, and buildings)
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Reduces amount of water soaking into the ground
Accelerates runoff to ditches and streams.
Humans also pollute bodies of water
Polluted water goes up in the air and eventually causes acid rain, which is
detrimental to the environment.
Source of Farming Problem
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Ammonium Nitrate is one of the most important ingredients in fertilizer.
Because Mrs. Hinz and Ms. Schuckers used fertilizer for their plants, it
most likely got into the water supply. When this nitrate-rich water
evaporates, it goes into the atmosphere and falls into and may collect in
the nearby lake as acid rain.
The source of the farming problem is Eutrophication.
The lake gets filled with a high amount of nitrates and an excessive
amount of algae grows inside the lake (hence the deep green water).
The water gets filled with more decomposers to try and balance out the
algae to water ratio and break down the organic matter.
Source of the Farming Problem (Cont.)
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Because of the massive amount of decomposers and microorganisms, the
oxygen is depleted in the water, as the decomposers use all of it to
decompose the algae.
The oxygen levels in the water are extremely low, and the fish and other
organisms cannot breathe (hence the dead fish floating).
Solution for the Farming Problem
● Use less fertilizer so less nitrates can enter the lake
● Attempt to clean the algae out of the lake
● Bring in more fish to promote population growth and
organism balance
Condensation
Solar
Energy
Precipitation
Transpiration
Evaporation
Evaporation
Run- Run
off -off
Collection
Eutrophication
Land
Water
Sources
http://water.usgs.gov/edu/watercycleevaporation.html
http://water.usgs.gov/edu/runoff.html
http://toxics.usgs.gov/definitions/eutrophication.html
http://water.usgs.gov/edu/watercyclecondensation.html