Transcript ozone up high in the Stratosphere

UV-Radiation
Ozone
CFC
Skin Cancer
The „bad“ ozone on the ground is very
different from the „good“ ozone up high
in the Stratosphere !!!!!!!!!
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Too much ozone in the Troposphere (on the gournd) has a
very different effect and can cause severe ailments:
Respiratory diseases (e.g. asthma); especially endangered are
children, the elderly and people under severe physical strain
Inflammation
Nausea
Changes in blood count
Effects on the nervous system (exhaustion, decline in
performance).
Damage to forests
Corrosion of metallic items
Deterioration of buildings (monuments)
Contents
1.
UV - Radiation
2.
Skin Cancer
3.
Skin Structure
4.
The Ozone Layer
5.
CFC and Alternatives
What is UV-Radiation?
Visible light ranges between 390nm - 770nm.
UV – light is located below 390nm.
 UV-B and UV-C are more harmful; they do not penetrate
the skin very deeply, but rather react in the Epidermis and
Dermis.
The Spectrum of Sunrays
52% visible light
44% invisible Infrared radiation
4% UV - radiation
(These are the most dangerous to skin!)
Consequences of Increased UVRadiation
1.Skin cancer
2.Examples of other illnesses
3. Effects on nature
Damage caused by radiation
The major dangers are inflammatory
reactions (sunburn) and damages to the
DNA of the skin cells, which can lead to
skin cancer.
Benign melanomata
and malignant melanomata
are the two possible types of skin
cancer that can develop. The
malignant melanomata are also called
black skin cancer.
Benign melanoma
Nodular melanoma (NM).
Malignant melanoma
Superficial spreading
melanoma (SSM)
The malignant melanoma
- black skin cancer Very harmful tumour
Place of development: It develops in the cells that give the
skin its color (melanocytes)
Development: On normal skin or allready existing cellular
nevus (mole, birthmark)
Starting point: Basal cells;
At first it usually grows in a horizontal direction being
rather superficial but depending on the type of
melanoma it may start growing rapidly in a vertical
direction at an early stage.
Ca. 20% of all melanomata belong to the so
called nodular melanoma (NM). The NM
varies in colour from blue to dark brown.
Melanoma is so dangerous, because once it
grows to a certain thickness, it metastasizes
or spreads throughout the body. After
melanoma has spread to the internal organs
there is little that can be done and death
follows shortly after.
The superficial spreading melanoma (SSM) accounts for about
60% of all melanomata and is the most common type. SSM
undergoes two growth phases. During the "radial" phase, the
lesion expands through the epidermis (upper skin layer). In
the early radial phase, which may last months or years, the
lesion is thin. After the radial phase, a "vertical" growth phase
begins. It may contain areas of tan, brown/black, red, dark
blue/purple, or white coloration. This melanoma often appears
as a flat „spot“ with regular borders.
The structure of the skin
The impact of UV - radiation
Do we all react alike?
Because of the advancing loss of Ozone within the
stratosphere, the intensity of the UV-radiation increased
noticeably. The sensitivity towards UV-A-radiation
depends on the skin type.
We all react alike towards UV-B and UV-C, because those
rays were not planned to reach the earth at all.
The 4 different skin types
Skin type 1
Skin: Strikingly fair, pale
Hair: Fair blonde to reddish
Eyes: Green, blue
Reaction to sun: Always, severe, painful
Tan: No tan
Sunburn after: 10 min.
Skin type 2
Skin: Fair
Hair: Blond to brown
Eyes: Grey, blue, green
Reaction to sun: Mostly, severe
Tan : Moderate tan
Sunburn after: 15 min.
The 4 different skin types
Skin type 3
Skin: Light tan, olive
Hair: Deep blonde, brown
Eyes: Grey, brown
Reaction to sun: Rarely, moderately
Tan: Good tan
Sunburn after: 20-30 min.
Skin type 4
Skin: Brown
Hair: Deep brown, black
Eyes: Brown
Reaction to sun: Hardly any
Tan : Fast and deep; very good tan
Sunburn after: 40-60 min.
Examples for other illnesses
 Damage to the eyes
 General weakening of the immune system
Effects on nature
A permanent damage to the environment leaves broad
features on plants:
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Retrenchment of the photosynthesis
Shorter sprouts
Decrease of the average leaf surface
Alterations within the plant communities
These alterations could lead to extensive crop loss and to
changes within the food chain or could contribute to forest
dieback.
Effects on nature
The nutrient-rich phytoplankton (e.g. Algaes)
decline in the seas. As the process develops the following
tendencies become apparent:
 Lack of food for fish and changes in the
composition of species
 Loss of the greatest producer of oxygen, as well as less
conversion of CO2
 Increase of the greenhouse effect
The Ozone Layer
Situation and structure
General information about the
Ozone layer
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The Ozone layer is
located in the
stratosphere.
The highest
concentration of Ozone
exists at a height from 20
to 25km and serves as a
shield against UV-B and
UV-C radiation.
This is the only way life
on earth, as we know it
today, is possible.
Structure of the Atmosphere
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Our habitat is situated in the Troposphere
The Arctic Hole in the Ozone
Layer
Why above the Antarctic?
The graph to the right
shows the measured total
ozone above the Halley Bay
station in Antarctica.
Why above the Antarctic?
 Owing to temperatures of - 80° C water vapour condensates
in the stratosphere. PSCs form and are made of ice, nitric acid
and sulphuric acids.
(PSC = Polar Stratospheric
Clouds).
 The HCl and ClONO2
molecules are able to react with
the ice crystals of the PSCs.
HCl is tied to the surface of the ice crystals and reacts with
the ClONO2 molecule. Thereupon, molecular Chlorine (Cl2)
is released.
Why above the Antarctic?
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The descent of the cooling airmasses causes a cyclical,
circumpolar votex. It encloses the cool air above the
poles and prevents the warmer, more ozoniferous
airmasses from reaching the lower latitudes.
The Future of the Ozonehole
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Due to the long lifespan of CFC it will take
approximately 50 years before the already
released CFCs in the stratosphere are removed.
Furthermore,
the use of CFC
did not
completely stop
in spite of
agreements
such as the
Montreal
Protocol and
CFC
1. CFC – Where are they found?
2. Climate friendly alternatives and
their disadvantages
What are CFC‘s?
CFC is an abbreviation for
Chlorofluorocarbons.
They were used in fire extinguishers,
aerosol sprays and refrigerators.
They can exist in the environment for 45300 years, as they are generally nonreactive.
Why does CFC destroy the
ozone?
 UV-radiation breaks off the chlorine atom of the CFC.
 The chlorine atoms and Ozone react. Ozone is destroyed
 At the same time Chloroxide develops and reacts with the
Ozone.
 Ozone is destroyed, and the chlorine atoms are released again.
 This continuous chain reaction destroys the Ozone.
Climate friendly alternatives
Refrigerants (since the 30s) have
been replaced by the following:
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Since January 1st, 1995 CFC is no
longer used in car air
conditioners and refrigerators.
Instead of CFC, Isobutane is used
in today‘s refrigerators.
Ammonia and Propane are used
in commercial new construction.
Also used, is H-FC, which is
harmless to the Ozone.
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Prohibited in foam plastics,
pentane or cabondioxide are used
instead.
Prohibited in insulation since 1994 ,
glas-/ rock wool, animal or herbal
fibres are used instead.
Prohibited since 1992 in detergents
and solvents, water-based detergents
are increasingly used.
Prohibitied in fire extinguishers
since 1994 , carbon dioxide , water,
foam and powder are used instead.
Prohibited early in aerosol sprays,
they are still used in special
applications (antiasthmatic sprays).
Further climate friendly alternatives
and their disadvantages
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Hydrocarbons (propane, isobutane, pentane) 
flammable
Carbon dioxide  harmful to the environment and
climate: greenhouse effect.
Water some substances lose their attributes by
reacting with water.
Ammonia  could transform into ammonium
compound, that could lead to an eutrophication of
bodies of water and vegetation. Additionally,
ammonia is very toxic.
Thank You