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THE GREENHOUSE EFFECT AND THINNING OF THE
OZONE LAYER ON THE ECOSYSTEM
NAME:NOOR SHAHIRAH BTNORDIN
CLASS:4 HAWA
TEACHER: PN..ROHAIZA BT. BAHARI
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THE GREENHOUSE EFFECT.
What is greenhouse effect
Greenhouse gases warm the atmosphere, thermal
radiation is absorbed by the planet and the temperature
increases. This phenomenon is called greenhouse effect
as its mechanisms are similar to the processes which
occur in a greenhouse. In this case the atmosphere of the
planet functions as glasswhich enables to heat the
surface from one side and from the other side it absorbs heat emitted by the surface
thereby causing global increase in temperature. To be brief, the atmosphere andgases it includes allow the radiation emitted by the Sun to get inside; however, at
the same time, they trap the radiation of the heatedEarth and do not allow it to
escape and direct it towards the surface again. We receive the same amount of
energy but the accumulation of the compounds which trap the Earth radiation in theatmosphere favors the increase in temperature.
Gases and aerosols are responsible for this.
Greenhouse effect is a thoroughly natural phenomenon which was observed not
only on the Earth but also on other celestial bodies in our solar system, namely onMars, Venus and Titan (moon of Saturn).
Natural greenhouse effect
The greenhouse effect is essential to life on our planet. Due to the ability to
absorb and trap part of heat, it was possible for life to be created and survive. The
greenhouse effect, owing to the specific role of atmosphere on every planet, is a
natural phenomenon. Only on the Earth it takes on alarming proportions due to
human activity. Natural heating of the planet is the effect of heat exchange. Thisprocess looks as follows: solar radiation carries thermal energy, when it reaches the
Earth, it heats the atmosphere and the surface; water, forests and
wholeenvironment are heated as well. The Earth does not absorb the whole
radiation, some of it is reflected; every light surface which reflects light also
reflects thermal energy. This process is increased by some compounds and
formations contained in the air (clouds, some aerosols). On the other hand, clouds
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and some gases let in and absorb energy thereby increasing temperature. Heating is
not a one-way process. Ultraviolet objects heated by radiation emit all or part of
radiation in a reverse process - long-wave infrared radiation. But for the atmosphere
and the presence of compounds limiting the emission outside, all radiation would
be transmitted to space. Nevertheless, the returned emission is stopped, heat
balance of the Earth is positive, i.e. the amount of heat which reaches the Earth
exceeds the amount of heat which leaves the Earth. This process leads to increase in
temperature.
The causes of the greenhouse effect
The atmosphere of our planet is the air which is the mixture of various gases and
aerosols. The composition of the atmosphere depends on the height. To put it
simply, this is a composite mixture of gases. The most common gases are nitrogen
(over 78%) and oxygen (28%). Other gases constitute only a fraction of the wholemixture; however, we cannot ignore their importance.
The main greenhouse gas is water vapour. According to scientists, it is
responsible for the greenhouse effect in 30 to 60 per cent. The amount of the
vapour in the atmosphere is not fixed and it fluctuates depending on a time of the
day, season or area. Clouds are made of vapour, its presence can be easily stated
with our own eyes. The vapour is also significant due to the fact that, on one hand,
it absorbs perfectly some solar radiation and, on the other hand, it substantially
limits heat return in the form of infrared radiation. Its presence in the atmosphere is
the result of evaporating water: seas, lakes, oceans and also evaporating water fromground, plants and other organisms. The atmosphere is cleaned by rainfall and the
process of vapour exchange and water cycle in the nature is dependant on
temperature: the higher temperature the higher water evaporation rate; as a result
the content of water vapour in the air increases and so does the greenhouse effect.
Another greenhouse gas is carbon dioxide. It was discovered in the atmosphere a
long time ago and it is one of the factors responsible for life-friendly temperature.
However, as the result of the emission of carbon dioxide in the process of fuel
burning and forest burning, its greenhouse effect increases and so does its influence
on climate. Carbon dioxide is responsible for the greenhouse effect at about 9 to
26% and the ability to absorb infrared radiation is 1. Methane has a considerable
influence on climate warming. This gas is produced in natural processes, mainly by
bacteria which decompose organic matter (remains of plants and animals). The
excess of methane in the air and thereby enhancing the greenhouse effect are
caused by mining industry and stockpiles of organic waste (dumps). The ability of
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methane to absorb infrared radiation is thirty times higher than the ability
of carbon dioxide.
Other gases which cause and enhance the greenhouse effect (as a result of
emission caused by people) are nitric oxides, including nitrous oxide, ozone and
CFCs. The ability of nitrous oxide to absorb thermal radiation is 150 higher thanthe ability of carbon dioxide; this gas is produced in the emission of exhaust fumes
and while using nitric fertilizers in farming.
Ozone, which is the protective ozone sphere in upper layers, in lower layers
prevents heat produced on the Earth from escaping and its absorbency is 200 times
higher than the same abilities of carbon dioxide. The content of greenhouse ozone
increases due to chemical reactions of carbon monoxide, hydrocarbons and nitric
oxides emitted in industrial burning processes.
And finally CFCs which are not natural as they were produced by people.
Although there are not many CFCs in the air, their ability to trap radiation is from
ten to twenty thousand higher than the ability of carbon dioxide.
Greenhouse effect and global warming
The issue of the greenhouse effect on climate change is debatable even in a
scientific environment. Nevertheless, it is widely assumed that the greenhouse
effect or its intensification resulting from human activity, has impact on global
warming. The facts are clear: within the space of one century, i.e. from thebeginning of the 20th century to the beginning of the 21st century, average
temperature increased by 0.7%. What is more, there was a rise in the emission of
carbon dioxide and other greenhouse gases. The estimated probability that it was
caused by human activity and not by natural reasons is 90% (data from IV Report
of the Intergovernmental Panel on Climate Change). Scientists who are skeptical
about this theory claim that this change was caused by change in the activeness of
the Sun which always influenced our planet, even before the intensification of
human industrial activity.
There are other examples of climate change, such as a rise in averagetemperature on poles (the Arctic - average yearly temperature increased by 3
oC and
by 7oC in winter), changes in a moderate climate - which can be observed in hot
summers and relatively warm winters. Furthermore, climatic zones are shifting to
the Equator and, as a result, areas on which droughts occur are extending.
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If this process continues, in the next century the consequences will be much
more worrying: permafrost melting will cause the creation of bogs which
consequently will increase the emission of methane and carbon dioxide. Due to the
increase in the amount of carbon dioxide and methane in the air, the temperature of
the Earth will rise by about 2oC which will influence ice melting and cause level of
water to rise, as a result vast areas of the Earth will be threatened with flooding.From 1880 to 1990 the level of seas and oceans increased by about 11 cm.
Air circulation may be disturbed, climatic zones will shift, we will lose huge
areas of farming lands and forest areas. Paradoxically global warming may lead to
another Ice Age (ice melting will prevent warm sea currents).
To sum up, scientists agree that the greenhouse effect enhanced by people will
speed up the process of global warming and global climate changes which may lead
to unpredictable consequence in the future - even extermination of humankind andlife on the Earth.
Forests and greenhouse effect
One of the main greenhouse gases responsible for the greenhouse effect,
examples, gases which absorb heat and trap it in the Earth atmosphere, is carbon
dioxide. It is widely known that this gas is converted into oxygen by plants
(photosynthesis). It means that the presence of carbon dioxide in the air is closely
associated with the condition of plants on the Earth. Being a treasure trove of plants
and lungs of our planet, forests are of great importance.
Most of forest areas have been destroyed and some of them are still being
destroyed due to territorial expansion. They are cut down and burnt down. As a
result of both processes we lose vast areas of forests which regulate gas and thermal
economy of our planet. By burning forests we contribute to increase in the emission
and concentration of carbon dioxide in the atmosphere.
Forests also absorb humidity thereby protecting the air from the excess of carbon
dioxide. High humidity facilitates storing carbon dioxide in lower layers of the
atmosphere owing to which it is kept in forests and does not escape to higher layerswhere it could cumulate heat. According to scientists' opinion, about 15% of the
emission of carbon dioxide to the atmosphere is the effect of the destruction of forest areas.
Another problem connected with the greenhouse effect is destruction of rain
forests. Not only are these huge green areas the treasure trove of nature and a place
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where oxygen is produced, they also regulate the amount of heat and light absorbed
and reflected by the Earth. The ration of light reflection is called albedo. The colors
of forests are dark so they absorb light radiation. If forests are destroyed, the light is
reflected. Significant changes in the albedo ration influence winds, sea currents and
rainfall, in other words, they cause climatic changes.
TINING OF THE OZONE LAYER ON THE ECOSYSTEM
What is the ozone hole
The phenomenon of the ozone hole was first observedin the 1980s over the Antarctic. The ozone hole is the
ozone depletion in the upper layer of the Earth's
atmosphere, so-called stratosphere. It is said that the
ozone loss is about 50% due to the emission of
compounds which cause a ozone depletion - particularly
CFC - the protective ozone layer was damaged at theheight of 10 to 50 kilometers.
Research demonstrated that during the last several years the concentration of ozone in the atmosphere fell by 0,2% per annum. The phenomenon is called the
ozone hole extension. What is worse, it appears not only over the Antarctic but also
over other areas on the Earth.
Effects on Human Health
Laboratory and epidemiological studies demonstrate that UVB causes
nonmelanoma skin cancer and plays a major role in malignant melanoma
development. In addition, UVB has been linked to cataracts -- a clouding of the
eye’s lens. All sunlight contains some UVB, even with normal stratospheric ozonelevels. It is always important to protect your skin and eyes from the sun. Ozone
layer depletion increases the amount of UVB and the risk of health effects.
EPA uses the Atmospheric and Health Effects Framework (AHEF) model,
developed in the mid 1980s, to estimate the health benefits of stronger ozone layer
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protection policies under the Montreal Protocol. EPA estimates avoided skin cancer
cases, skin cancer deaths, and cataract cases in the United States.
Effects on Plants
Physiological and developmental processes of plants are affected by UVB
radiation, even by the amount of UVB in present-day sunlight. Despite mechanisms
to reduce or repair these effects and a limited ability to adapt to increased levels of
UVB, plant growth can be directly affected by UVB radiation.
Indirect changes caused by UVB (such as changes in plant form, how nutrients are
distributed within the plant, timing of developmental phases and secondary
metabolism) may be equally, or sometimes more, important than damaging effectsof UVB. These changes can have important implications for plant competitive
balance, herbivory, plant diseases, and biogeochemical cycles.
Effects on Marine Ecosystems
Phytoplankton form the foundation of aquatic food webs. Phytoplankton
productivity is limited to the euphotic zone, the upper layer of the water column in
which there is sufficient sunlight to support net productivity. The position of the
organisms in the euphotic zone is influenced by the action of wind and waves. Inaddition, many phytoplankton are capable of active movements that enhance their
productivity and, therefore, their survival. Exposure to solar UVB radiation has
been shown to affect both orientation mechanisms and motility in phytoplankton,
resulting in reduced survival rates for these organisms. Scientists have
demonstrated a direct reduction in phytoplankton production due to ozone
depletion-related increases in UVB. One study has indicated a 6-12% reduction in
the marginal ice zone.
Solar UVB radiation has been found to cause damage to early developmental stages
of fish, shrimp, crab, amphibians and other animals. The most severe effects aredecreased reproductive capacity and impaired larval development. Even at current
levels, solar UVB radiation is a limiting factor, and small increases in UVB
exposure could result in significant reduction in the size of the population of
animals that eat these smaller creatures.
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Effects on Biogeochemical Cycles
Increases in solar UV radiation could affect terrestrial and aquatic biogeochemical
cycles, thus altering both sources and sinks of greenhouse and chemically-
important trace gases e.g., carbon dioxide (CO2), carbon monoxide (CO), carbonyl
sulfide (COS) and possibly other gases, including ozone. These potential changes
would contribute to biosphere-atmosphere feedbacks that attenuate or build up of
these reinforce the atmospheric gases.
Effects on Materials
Synthetic polymers, naturally occurring biopolymers, as well as some other
materials of commercial interest are adversely affected by solar UV radiation.
Today's materials are somewhat protected from UVB by special additives.
Therefore, any increase in solar UVB levels will therefore accelerate their
breakdown, limiting the length of time for which they are useful outdoors.
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More Information
Environmental Effects of Ozone Depletion and Its Interactions with Climate
Change: 2010 Assessment
This report by the experts who comprise the Environmental and Health
Effects Assessment Panel (appointed under the Montreal Protocol) explains
the effects of ozone depletion on human and environmental health.
Q&A on the effects of the depletion of the ozone layer on humans and the
environment
Answers to SunWise program about health effects linked to UV exposure, frequently
asked questions about the impact of ozone layer depletion on human health
and the environment. These questions and answers were prepared by the
experts who comprise the Environmental and Health Effects Assessment
Panel (appointed under the Montreal Protocol).
Health Effects of Ozone Depletion
A detailed explanation from EPA's including skin cancer, other skin
problems, cataracts, and immune system suppression.
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Greenhouse gases are trapped and build up in the atmosphere near the
earth’s surface. This makes the earth warmer than normal. The warning
effect of the trapped greenhouse gases causes changes in the weather
patterns on a global scale. Rainfall pattern changes, sea level rises and
droughts prevail.
Image via Wikipedia
The greenhouse effect refers to the phenomenon whereby earth’s
temperature increases as a result of heat being trapped in its
atmosphere. The greenhouse gases are gasses that trap heat and
then warm up earth with this heat. These gases include carbon dioxide,
carbon monoxide, methane and CFC. The percentage of carbon dioxide
has been increasing over the past 10 years due to the increasing usage of
fossil fuels.
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http://u.nu/2gmw
or: http://u.nu/7gmw
Greenhouse effect can be likened to the glass house effect. The glass
house is used in countries with four seasons for agricultural purposes. It
allows light to penetrate but disallows the reflection of heat energy. This
creates a warming effect. Greenhouse gases include carbon dioxide,
nitrogen oxides and methane. The trapped heat energy increases theearth’s temperature. The warming of the earth which is referred to as
the green house effect leads to the following negative effects a) Melting of
ice at the poles b) Increase in sea level c) Climatic changes d) Increase in
the rate of disease outbreak for example diseases like malaria dengue
fever.
Global Warming
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Read more in Ecology
« Pythons in the Backyard of America: The Menace of an Invasive Species
The Adaptations of Animals »
Image via Wikipedia
Greenhouse gases are trapped and build up in the atmosphere near theearth’s surface. This makes the earth warmer than normal. The warning
effect of the trapped greenhouse gases causes changes in the weather
patterns on a global scale. Rainfall pattern changes, sea level rises and
droughts prevail.
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The Thinning of the Ozone Layer
http://u.nu/5imw
or: http://u.nu/2imw
Ozone which forms a layer in the stratosphere is made up of three atoms of
oxygen (O3). Stratospheric ozone protects the Earths’ surface from highlevels of biologically damaging ultraviolet (UV) radiation.
Chlorofluorocarbons (CFC), the main made chemicals, are implicated in
ozone loss. CFCs are a group of compounds made from chlorine (C1),
fluorine (F) and carbon (C). They are by products of industrial activity, not
poisonous, they cannot be burnt and are very stable because are not
reactive with other compounds.
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Image via Wikipedia
CFC’s are not broken down in the troposphere. They are able to reach the
stratosphere (where the ozone is). Because of their physical characteristics,
CFC are ideal for many industrial processes a) CFCs and use as a coolant
in refrigerators, in air conditioners for automobiles, hoses and buildings.
This CFC will only be released into the atmosphere when the coolant isbroken. Alternative coolant compounds are now available which do not
damage the ozone layer b) for manufacturing foam used for packing
materials, mattresses and insulation. CFCs are released into the
atmosphere during the manufacture during the manufacture processes c)
used as propellants in aerosol cans in the cosmetic industry, and in
insecticides. CFCs are released into the atmosphere when an aerosol is
used. This can be overcome by using an alternative like oxygen instead of
the propellant gases used in aerosols or to use aerosols with a pump
system.
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http://u.nu/8b89
or: http://u.nu/3kmw
CFCs are extremely stable compounds. But when they reach the
stratosphere CFCs are broken down by ultraviolet rays. This is how CFC
depletes the ozone layer in the stratosphere a) Ultraviolet rays strikes aCFC molecule causing a chlorine atom to break away b) the free chlorine
atom then collides with an ozone molecule and combines with an oxygen
atom to form chlorine monoxide leaving an oxygen molecule.
http://u.nu/6rmw
or: http://u.nu/4rmw
c) when a free oxygen atom then collides with chlorine monoxide two atoms
of oxygen. The free chlorine atom continues to destroy the ozone
molecules. Thus it is advisable to avoid long periods of exposure to direct
sunlight d) an increase in ultraviolet rays harms the ecosystem by
interfering with nitrogen assimilation by microorganisms. Nitrogen is an
important element in the synthesis of protein. This will cause the decline in
rice production and other cultivated crops.
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http://u.nu/8b89
or: http://u.nu/2mmw
Ways to Reduce Ozone Depletion
Image via Wikipedia
Reduce the use of CFC and replace CFC with HCFC
(Hydrochloroflurocarbon). Deactivate CFC before release into the
atmosphere. Reduce the usage of materials that uses ozone depletingsubstances like tetra-chloromethane and methyl-chloroform in the
production of polystyrene.
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Read more: http://scienceray.com/biology/ecology/the-greenhouse-effect-and-the-thinning-of-the-ozone-layer/#ixzz1d8ISROlG
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What is the meaning of green house effect?
Green house effect is a process in atmospheric physics that traps heat in the Earth's
atmosphere. It is the result of physical interaction between components of the atmosphere
(greenhouse gases) and incoming sunlight.
It is not a layer of carbon dioxide in the sky that reflects heat back down as it radiates from
the Earth's surface. Heat is absorbed by the carbon dioxide all through the atmosphere and the
warmer gas "shares" its heat with all the atmospheric gases increasing the average
atmospheric temperature
Greenhouse gases are trapped and build u p in the atmosphere near the earth’s surface. This
makes the earth warmer than normal. The warning effect of the trapped greenhouse gases
causes changes in the weather patterns on a global scale. Rainfall pattern changes, sea level
rises and droughts prevail.
The greenhouse effect refers to the phenomenon whereby earth’s temperature increases as a
result of heat being trapped in its atmosphere. The greenhouse gases are gasses that trap heat
and then warm up earth with this heat. These gases include carbon dioxide, carbon monoxide,
methane and CFC. The percentage of carbon dioxide has been increasing over the past 10
years due to the increasing usage of fossil fuels.
Greenhouse effect can be likened to the glass house effect. The glass house is used in
countries with four seasons for agricultural purposes. It allows light to penetrate but disallows
the reflection of heat energy. This creates a warming effect. Greenhouse gases include carbondioxide, nitrogen oxides and methane. The trapped heat energy increases the earth’s
temperature. The warming of the earth which is referred to as the green house effect leads to
the following negative effects a) Melting of ice at the poles b) Increase in sea level c)
Climatic changes d) Increase in the rate of disease outbreak for example diseases like malaria
dengue fever.
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Global Warming
Greenhouse gases are trapped and build up in the atmosphere near the earth’s surface. This
makes the earth warmer than normal. The warning effect of the trapped greenhouse gases
causes changes in the weather patterns on a global scale. Rainfall pattern changes, sea level
rises and droughts prevail.
The Thinning of the Ozone Layer
Ozone which forms a layer in the stratosphere is made up of three atoms of oxygen (O3).
Stratospheric ozone protects the Earths’ surface from high levels of biologically damaging
ultraviolet (UV) radiation. Chlorofluorocarbons (CFC), the main made chemicals, are
implicated in ozone loss. CFCs are a group of compounds made from chlorine (C1), fluorine
(F) and carbon (C). They are by products of industrial activity, not poisonous, they cannot be
burnt and are very stable because are not reactive with other compound.
CFC’s are not broken down in the troposphere. They are able to reach the stratosphere (where
the ozone is). Because of their physical characteristics, CFC are ideal for many industrial
processes a) CFCs and use as a coolant in refrigerators, in air conditioners for automobiles,
hoses and buildings. This CFC will only be released into the atmosphere when the coolant is
broken. Alternative coolant compounds are now available which do not damage the ozone
layer b) for manufacturing foam used for packing materials, mattresses and insulation. CFCs
are released into the atmosphere during the manufacture during the manufacture processes c)
used as propellants in aerosol cans in the cosmetic industry, and in insecticides. CFCs are
released into the atmosphere when an aerosol is used. This can be overcome by using an
alternative like oxygen instead of the propellant gases used in aerosols or to use aerosols with
a pump system.
CFCs are extremely stable compounds. But when they reach the stratosphere CFCs are
broken down by ultraviolet rays. This is how CFC depletes the ozone layer in the stratosphere
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a) Ultraviolet rays strikes a CFC molecule causing a chlorine atom to break away b) the free
chlorine atom then collides with an ozone molecule and combines with an oxygen atom to
form chlorine monoxide leaving an oxygen molecule.
c) when a free oxygen atom then collides with chlorine monoxide two atoms of oxygen. The
free chlorine atom continues to destroy the ozone molecules. Thus it is advisable to avoid
long periods of exposure to direct sunlight d) an increase in ultraviolet rays harms the
ecosystem by interfering with nitrogen assimilation by microorganisms. Nitrogen is an
important element in the synthesis of protein. This will cause the decline in rice production
and other cultivated crops.
Ways to Reduce Ozone Depletion
Reduce the use of CFC and replace CFC with HCFC (Hydrochloroflurocarbon). Deactivate
CFC before release into the atmosphere. Reduce the usage of materials that uses ozone
depleting substances like tetra-chloromethane and methyl-chloroform in the production of
polystyrene.