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Environmental Science
Course Code
Jovan Stefanovic

of 5
Lecture #11: Global Climate Change, Ozone Depletion and Human Health
Wednesday, April 6th/2011
The question nowadays is not anymore that Is climate change really happening?
Instead questions are that:
oHow fast is it going to happen?
oWhen are we going to see its health effects?
oHow much are humans affecting/speeding up the rate of climate change,
through human emission?
oWhat is the role of human emission?
Climate is changing, normally; has been changing over the millenniums, nothing
Over time, phases of climate: Glaciations, warm periods normally alternating
through history
This process is much faster right now
Things that used to take millenniums and hundreds of years to occur, are now
happening much faster
Greenhouse effect: keeps planet warm, very unpleasant place if there is no such
Water vapour as one very important greenhouse gas -- #1 greenhouse gas, since its
not produced by the industry and is not a human emission, we dont really talk about
it; however, its role is very imp in keeping the planet warm
Home is the largest emitter of co2, Canada is at the 8th place, but is 4X the global
average, therefore its a lot
Evidence for climate change
Importance of co2 in atmosphere and how that concentration of CO2 is directly
proportional to global temperature
Processes affecting increase of greenhouse gases combustion, fossil fuels, burning =
#1, transportation, industries also some biological processes using inorganic
fertilizers is emitting nitric acids, also growing rice is emitting nitrogen gases,
livestock burning their organic matter releases methane also a greenhouse gas
Health effects or potential health effects of climate change graph summarizes
almost all health effects we CAN expect, but its not known, n one really knows will
happen, models can only predict **IMP*** REVIEW THIS SLIDE for FINAL
Ozone Depletion
Lots of ozone significantly may affect the health bad UV rays, such as A, mostly C,
B are filtered through ozone layer; good ozone in stratosphere is filtering bad UVS,
not ground-level ozone; since ozone layer is thinning not holes due to the release
of CFCs chlorofluorocarbons has been incorporated into some products like hair
sprays, cooling products in fridge cause the breakdown of ozone and producing
elemental oxygen and O2
Now bad UVs such as UVBs and Cs have been able to reach the ground and effect
humans..not just humans also all other living organisms and also other materials as
well e.g. construction materials, textiles, wood, causing deteriorating of these
materials as well
Human health dramatic increase in dermal cancer blaming bad UV rays extremely
high increased rate of these types of cancer
Cataracts also are increasing esp. in countries like India or countries with lots of
sunlight, not always related directly just to ozone depletion also related to amount of
sunlight exposure; huge numbers of people getting cataracts in South Asian
countries and many get them operated
Outer immune system basically decreasing the immunity to some other illnesses
simple illnesses like cold, flu; not rare that if you are sunbathing for a couple of
days, your immune system gets weaker
Wildlife and other animals and plants are also being effected by UV spectra
Last decade there have also been increase warnings about effects of UVA part of
We thought they werent causing problems but now some types of skin cancers have
been related to UVA; many research is going on now to look at its effects , we know
UVB and C are really damaging lots of research being done on UVA
Since discovery of fire, human being as have been effecting the envmt significantly
and other species as well, before that there was very mild effect on envmt and other
species was very very low; effects has been never so big since Industrial evolution,
extreme number of other species other than humans have been eliminated and
extinct and gone forever
If you have a site that has been contaminated, regardless of the contaminant we can
partially or completely restore/remediate that site, maybe not put it back in original
condition but still use it in some way for something, still useable but if a species is
gone, it is gone forever, no way that same species will come back, maybe another
similar species but not the same one; thats why this is called the BIGGEST LOSS of
all most of this has been caused by human activities
Loss of wetlands—Wetlands have been dried out for different purposes, some for
agriculture, roads, buildings they are the most richest and diverse
envmts/ecosystems; extremely rich in species, plants, vegetation etc.
What are the potential threats of losing environments
Extinction threats
Ozone depletion
Chemical pollutionsame as humans to plants and other organisms
Acid rain contaminates the soil, reduces number of species, and forests are dying,
negatively affected by acid rain, lakes (beautiful European, in high mountain) are
dyingvery clean, not chemically polluted but very acidic right now, just b/c of acid
rain, species have been affected in those lakes, bnumber of species that can survive
in acidic conditions in very low
Habitat Loss/Degradation of Habitat very imp for some animals to have certain
size of habitat, they cant survive in reduced habitat, they need spafce to move, to
find food, due to human activities those habitats have been disturbed, changes or
reduced size
Or fragmented, if in the middle of the area there is a road or recreation faciilty that
has been disturbing but also fragmenting the habitat, so the species living here can
be affected
Non-native species kudz wine? = plant , this is not a native species in North
America, mostly in USeffect of non-native species on environment and other