2. PLANNING FOR THE UNIT
Main topic: WATER
Properties of water
Water cycle
Hard water/soft water
Ocean acidification
Acid rain
Eutrophication
Main topic: AIR
Properties of the atmosphere/air
Oxygen
The carbon cycle
The (enhanced) greenhouse effect
The ozone layer
Main topic: Earth
Nitrogen cycle
Weathering & deposition (the rock
cycle)
The short/long carbon cycle
Fossil fuels
4. TASK
Draw a mindmap of the atmosphere
What is there and what happens in there?
Show interactions with the other spheres (lithosphere/rocks, biosphere/life,
hydrosphere/water)
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6. The atmosphere has not always
been like this, both abiotic and
biotic factors have caused huge
fluctuations.
Abiotic factors such as
temperature and precipitation.
Biotic factors such as plants and
animals.
Clues from:
• Sediments
• Fossils
• Gas trapped in ice
• Looking at other planets
Evolution of algae caused an
increase in oxygen (there was no
free oxygen before this).
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13. ALBEDO EFFECT OF CLOUDS
Albedo effect is to do with the amount of energy that a substance
reflects or absorbs.
Linked to how white an object it.
Clouds reflect and absorb a lot of solar energy.
They also trap heat below them depending on how thick and high they
are.
You may have noticed that cloudy nights are usually a lot warmer than
cloudless ones.
14. AIR CIRCULATION
Rising air
Warm and moist
Low density
Low pressure area
Falling air
Cool and dry
High density
High pressure area
Forms circulations
15. CORIOLIS EFFECT
Because of the spin of the earth
Objects (air currents, water currents
deflect
Makes storms swirl clockwise in the
Southern hemisphere and
counterclockwise in the Northern
Hemisphere
22. OZONE – O3
Balance between two ongoing processes
UV radiation passing through the Earth’s
upper atmosphere is absorbed by the
formation and destruction of ozone.
23. OZONE
UV (ultraviolet) radiation is
absorbed during the formation
and destruction of ozone into
oxygen (O2)
24. OZONE AND UV LIGHT
Allows UVa and UVb through, but blocks UVc waves
UVa - causes wrinkles
UVb - causes skin cancer
UVc - worst one because of damage to organisms/tissues
25. UV RADIATION ALSO AFFECTS OTHER LIVING ORGANISMS
Damage to photosynthetic
organisms.
Especially phytoplankton – basis
of many aquatic food webs.
26. BENEFICIAL EFFECTS OF UV
In animals stimulates the production of Vit D
Treat psoriasis and vitiligo (skin diseases)
Steriliser, water purifier
Forensics, lighting, lasers
27. DAMAGE TO THE OZONE LAYER
CFCs are usually very stable. However, in the high stratosphere the
UV radiation breaks them down releasing free chlorine atoms
(chlorine is very reactive).
28. HOGS (HALOGENATED ORGANIC GASES)
HOG’s are usually stable but break down into halogen atoms (F, Cl, Br, I, At)
which are highly reactive
Ex. (CFC = chlorofluorocarbon)
Cl and F are halogens
Organic = contains carbon
30. DAMAGE TO THE OZONE
Substance Use/source Kind of atom
released
Chlorofluorocarbons (CFCs or
freons)
Hydrochlorofluorocarbon (HCFCs)
Halons
Methyl bromide
Nitrogen Oxides (NO, NO2, N2O,
NOx)
ODS (Ozone-depleting substances)
31. DAMAGE TO THE OZONE
Substance Use/source Kind of atom
released
Chlorofluorocarbons (CFCs or
freons)
Propellants in spray
cans, plastic foam
expanders, refrigerants
Release chlorine
atoms
Hydrochlorofluorocarbon (HCFCs) As replacements for
CFCs
Release chlorine
atoms,
Stronger GHG
Halons Fire extinguishers Release bromine
atoms
Methyl bromide Pesticide Releases chlorine
and bromine atoms
Nitrogen Oxides (NO, NO2, N2O,
NOx)
Bacterial breakdown of
nitrates and nitrites in
the soil (intensive).
High-flying supersonic
aircraft
The nitrogen oxides
are converted to NO,
which reacts with
ozone
ODS (Ozone-depleting substances)
37. EFFECTS OF OZONE
Toxic gas and oxidising agent
Damage to plants
Degrades chlorophyll
Damage to humans
Breathing problems
Throat, eyes and nose irritation
Damage to things
Car tires, fabrics, some plastics
40. FORMATION OF PHOTOCHEMICAL SMOG
Factors that affect formation:
Local topography
Climate
Population density
Fossil fuel use
Thermal inversion
