1. Water Cycle
Dominican American Cultural
Institute
The Water Cycle
Name:
Dansel Urbaez Mendez
Code:
2008-01-1-2107
Teacher:
Sean Legere
Date:
February 15, 2011
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2. Water Cycle
Index
Page
Cover Page 1
Introduction 3
Water Cycle 4
Water 5
States of Water 6
Changes in State 7
The Cycle 8
Concepts of Water Cycle 10
Evaporation 10
Condensation 11
Precipitation 11
Surface Runoff 12
Infiltration 12
Transpiration 13
Cloud Formation 14
Cumulonimbus 15
Nimbostartus 15
Cirrocumulus 16
Altostratus 16
Conclusion 18
Reference Page 19
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3. Water Cycle
Introduction
Nowadays few people know what the water cycle is, it process
has a principal objective wich is to keep the planet with
enough water in everywhere.
I choose this topyc becouse is one of the processes that our
planet has and without it can’t work.
In the following pages I expect you to learn and understand
how the water cycle process works.
In this project I intend to show the differents parts of the
water cycle and every one knows the importance of it.
Also I will explain how important are the clouds and how it
works together with the process of water cycle.
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4. Water Cycle
Water Cycle.
The water cycle, also known as the hydrologic cycle or H2O
cycle, describes the continuous movement of water on,
above and below the surface of the Earth. Water can
change states among liquid, vapour, and ice at various
places in the water cycle. Although the balance of water
on Earth remains fairly constant over time, individual
water molecules can come and go, in and out of
the atmosphere. The water moves from one reservoir to
another, such as from river to ocean, or from the ocean
to the atmosphere, by the physical processes of
evaporation, condensation, precipitation, infiltration,
runoff, and transpiration. In so doing, the water goes
through different phases: liquid, solid, and gas.
The water cycle also involves the exchange of heat energy,
which leads to temperature changes. For instance, in the
process of evaporation, water takes up energy from the
surroundings and cools the environment. Conversely, in the
process of condensation, water releases energy to its
surroundings, warming the environment.
The water cycle figures significantly in the maintenance of
life and ecosystems on Earth. Even as water in each reservoir
plays an important role, the water cycle brings added
significance to the presence of water on our planet. By
transferring water from one reservoir to another, the water
cycle purifies water, replenishes the land with freshwater,
and transports minerals to different parts of the globe. It is
also involved in reshaping the geological features of the
Earth, through such processes as erosion and sedimentation.
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5. Water Cycle
In addition, as the water cycle involves heat exchange, it
exerts an influence on climate as well.
Water
Water is an integral part of life on this planet. It is an
odorless, tasteless, substance that covers more than three-
fourths of the Earth's surface. Most of the water on Earth,
97% to be exact, is salt water found in the oceans. We can
not drink salt water or use it for crops because of the salt
content. We can remove salt from ocean water, but the
process is very expensive.
Only about 3% of Earth's water is fresh. Two percent of the
Earth's water (about 66% of all fresh water) is in solid form,
found in ice caps and glaciers. Because it is frozen and so far
away, the fresh water in ice caps is not available for use by
people or plants. That leaves about 1% of all the Earth's
water in a form useable to humans and land animals. This
fresh water is found in lakes, rivers, streams, ponds, and in
the ground. (A small amount of water is found as vapor in the
atmosphere.)
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6. Water Cycle
States of Water
Water exists in three states- solid, liquid, and gaseous.
Liquid Water
Liquid water is found in many places. You see
liquid water coming out of the faucet, when
it rains, and running in a river. Pure liquid
water is free of salt, rocks, soil, and
garbage.
Solid Water
Ice, snow, and frost are examples of
water in the solid state. Liquid water
freezes at 0 degrees Celsius. Celsius is
scale that measures temperature. Winter
is a season that you see a lot of solid
water. Other examples of solid water are
ice cubes, icicles, ice on a skating rink.
Water as a Gas
Gas is invisible. Water in the liquid state may change to water
in the gaseous state. Waterevaporates to turn into a gas.
Gases are colorless and odorless. You cannot see gas ,but
sometimes you can hear it and smell it.
Water can evaporate or disappear with the help of heat.
Changes in temperature can increase the rate or how long it
takes water to evaporate. Evaporate means to disappear. It
evaporates off wet clothes hanging on a clothesline. Plants
release water vapor into the air. We breathe out water vapor.
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7. Water Cycle
Changes in State
Gas to Liquid
When a gas changes to a liquid, it goes through the process of
condensation. This is when the gas cools and loses energy.
Then the particles are forced to change state, from a gas to
a liquid.
Liquid to Solid
When a liquid changes to a solid, it goes through the process
of Freezing. This is when a liquid cools below the freezing
point and loses energy. Then the particles are forced to
change state, from a liquid to a solid.
Solid to Gas
When a solid changes directly to a gas, it goes through the
process of sublimation. The particles are forced to change
state.
Liquid to Gas
The process in which a liquid changes into a gas is
called Evaporation. When a liquid gains enough energy, it can
overcome all of the attracting forces. Then it changes state,
from a liquid to a gas.
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8. Water Cycle
The Cycle
Water is constantly being cycled between the atmosphere,
the ocean and land. This cycling is a very important process
that helps sustain life on Earth.
As the water evaporates, vapors rise and condense into
clouds. The clouds move over the land, and precipitation falls
in the form of rain, ice or snow. The water fills streams and
rivers, and eventually flows back into the oceans where
evaporation starts the process anew.
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9. Water Cycle
Water's state (solid, liquid or gas) is determined mostly by
temperature. Although water continuously changes states
from solid to liquid to gas, the amount of water on Earth
remains constant. There is as much water now as there was
hundreds of millions of years ago.
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10. Water Cycle
Concepts of Water Cycle.
There are six important processes that make up the water
cycle. These are:
Evaporation
Evaporation is the process where a
liquid, in this case water, changes
from its liquid state to a gaseous
state. Liquid water becomes water
vapor. Although lower air pressure
helps promote evaporation,
temperature is the primary factor.
For example, all of the water in a pot left on a table will
eventually evaporate. It may take several weeks. But, if that
same pot of water is put on a stove and brought to a boiling
temperature, the water will evaporate more quickly.
During the water cycle some of the water in the oceans and
freshwater bodies, such as lakes and rivers, is warmed by the
sun and evaporates. During the process of evaporation,
impurities in the water are left behind. As a result, the water
that goes into the atmosphere is cleaner than it was on
Earth.
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11. Water Cycle
Condensation
Condensation is the opposite of
evaporation. Condensation occurs
when a gas is changed into a
liquid. Condensation occurs when
the temperature of the vapor
decreases.
When the water droplets formed
from condensation are very small, they remain suspended in
the atmosphere. These millions of droplets of suspended
water form clouds in the sky or fog at ground level. Water
condenses into droplets only when there are small dust
particles present around which the droplet can form.
Precipitation
When the temperature and
atmospheric pressure are right,
the small droplets of water in
clouds form larger droplets and
precipitation occurs. The
raindrops fall to Earth.
As a result of evaporation, condensation and precipitation,
water travels from the surface of the Earth goes into the
atmosphere, and returns to Earth again.
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12. Water Cycle
Surface Runoff
Much of the water that returns to
Earth as precipitation runs off the
surface of the land, and flows down hill
into streams, rivers, ponds and lakes.
Small streams flow into larger streams,
then into rivers, and eventually the
water flows into the ocean.
Surface runoff is an important part of
the water cycle because, through
surface runoff, much of the water
returns again to the oceans, where a great deal of
evaporation occurs.
Infiltration
Infiltration is an important
process where rain water soaks
into the ground, through the soil
and underlying rock layers. Some
of this water ultimately returns
to the surface at springs or in
low spots downhill. Some of the
water remains underground and is called groundwater.
As the water infiltrates through the soil and rock layers,
many of the impurities in the water are filtered out. This
filtering process helps clean the water.
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13. Water Cycle
Transpiration
One final process is important in
the water cycle. As plants
absorb water from the soil, the
water moves from the roots
through the stems to the leaves.
Once the water reaches the
leaves, some of it evaporates
from the leaves, adding to the
amount of water vapor in the air.
This process of evaporation
through plant leaves is called
transpiration. In large forests,
an enormous amount of water will
transpire through leaves.
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14. Water Cycle
Cloud Formation
Precipitation is one key to the water cycle. Rain comes from
clouds, but where do clouds come from?
Through the process of evaporation and transpiration, water
moves into the atmosphere. Water vapors then join with dust
particles to create clouds. Eventually, water returns to Earth
as precipitation in the form of rain, snow, sleet, and hail.
All clouds contain water vapors. You rarely ever see clouds in
the desert because there is very little water to evaporate
and form clouds. Coastal regions can receive a lot of rain
because they pull up moisture from surrounding waters.
Cloud size are influenced by many complex factors, some of
which we still do not understand very well. These include:
heat, seasons, mountain ranges, bodies of water, volcanic
eruptions, and even global warming.
Differents kinds of clouds are:
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15. Water Cycle
Cumulonimbus
Cumulonimbus (Cb) is a type
of cloud that is tall, dense, and
involved in thunderstorms and other
intense weather. Cumulonimbus
originates from Latin: Cumulus
"accumulated" and nimbus "rain". It is
a result of atmospheric instability. These clouds can form
alone, in clusters, or along a cold front in a squall line. They
create lightning through the heart of the cloud. Cumulonimbus
clouds form from cumulus clouds (namely from cumulus
congestus) and can further develop into a supercell, a severe
thunderstorm with special features.
Nimbostartus
A Nimbostratus cloud is characterized by
a formless cloud layer that is almost
uniformly dark gray. "Nimbo" is from the
Latin word "nimbus", meaning rain. It is a
low to middle-level (family
C2) stratiform cloud that produces rain,
developing cloud basesbetween the
surface and 10000 ft (3000 m). This cloud
typically forms from altostratus in the
middle altitude range then subsides into
the low altitude range during precipitation.
Nimbostratus usually has a thickness of 2000 meters. In rare
cases, Nimbostratus can be very thin and accompanied by a
separate layer of altostratus divided by a cloudless layer.
Though found worldwide, nimbostratus is found more
commonly in the middle latitudes.
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16. Water Cycle
Cirrocumulus
Cirrocumulus clouds are high-altitude
clouds that usually occur at an altitude
of 5 km to 12 km. Like other cumulus
clouds, cirrocumulus clouds
signify convection. Unlike other cirrus
clouds, cirrocumulus include a small
amount of liquid water droplets,
although these are in a supercooled state. Ice crystals are
the predominant component, and typically, the ice crystals
cause the supercooled water drops in the cloud to rapidly
freeze, transforming the cirrocumulus into cirrostratus. This
process can also produce precipitation in the form of
a virga consisting of ice or snow. Thus cirrocumulus clouds are
usually short-lived.
Properly, the term cirrocumulus refers to each cloud, but is
typically also used to refer to an entire patch of cirrocumulus.
When used in this way, each cirrocumulus element is referred
to as a "cloudlet".
Altostratus
Altostratus is a cloud belonging to a
class characterized by a generally
uniform gray sheet or layer, lighter in
color
thannimbostratus and darker than cir
rostratus. The sun can be seen
through thin altostratus, but thicker
layers can be quite opaque. They can
look similar to lower altitude stratus clouds.
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17. Water Cycle
Altostratus is caused by a large air mass that is lifted
then condensed, usually by an incoming frontal system and can
be found over widespread areas. Altostratus clouds are
potentially dangerous, because they can cause ice
accretion on aircraft. Their altitude is from 6,500–20,000
feet (2,400–6,100 m). They are primarily composed of water
droplets.
Altostratus clouds can produce light precipitation, often in
the form of virga. If the precipitation increases in
persistence and/or intensity, the altostratus cloud may
thicken into Nimbostratus.
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18. Water Cycle
Conclusion
Once we studied the proces of water cycle we know that it is
indispensable for the worlds’ function since is the only way to
bring water to plants and animals, from this point of view
were not life in the planet if it doesn’t work well.
In this project we learned that only one percent of the
worlds’ water is available for human use, it means that we
need to be careful of the water.
After we know how important the water cycle is we should be
part of the people who try to maintain the world clean to keep
the live worlwide.
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19. Water Cycle
Reference page
http://en.wikipedia.org
http://www.mbgnet.net/fresh/cycle/index.htm
http://www.radford.edu/~sbisset/wqh2o.htm
http://ga.water.usgs.gov/edu/watercycle.html
http://www.nyu.edu/pages/mathmol/textbook/slg.html
http://www.elytradesign.com/ali/html/changes.htm
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20. Water Cycle
Reference page
http://en.wikipedia.org
http://www.mbgnet.net/fresh/cycle/index.htm
http://www.radford.edu/~sbisset/wqh2o.htm
http://ga.water.usgs.gov/edu/watercycle.html
http://www.nyu.edu/pages/mathmol/textbook/slg.html
http://www.elytradesign.com/ali/html/changes.htm
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21. Water Cycle
Reference page
http://en.wikipedia.org
http://www.mbgnet.net/fresh/cycle/index.htm
http://www.radford.edu/~sbisset/wqh2o.htm
http://ga.water.usgs.gov/edu/watercycle.html
http://www.nyu.edu/pages/mathmol/textbook/slg.html
http://www.elytradesign.com/ali/html/changes.htm
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