18 - 2 Flashcards
Growing agreement that the temperatures will continue to rise
High latitudes will warm faster due to melting ice
Land areas will warm faster than the ocean
Possible consequences of continued warming include:
Increased rainfall in some areas and drought in others
Increased mortality from heat stress, urban air pollution and tropical diseases
Death from extreme weather events – tornadoes, hurricanes
A poleward shift of 150 – 500km in the location of vegetation zones
Increasing and drastic melting of the polar ice caps
Three billion people live in environments that are vulnerable to the impacts of climate change
Felt most acutely by the poorest and underdeveloped nations
Reduced food and water security
Irreversible loss of marine ecosystems
Changes suggest modification of agricultural practices, enhancement of flood protection and diversification of tree species
Thinning of the Ozone
The ozone is an invisible layer in the atmosphere
Shields the earth from ultraviolet rays (UV)
Since the mid-1980’s scientists have observed a seasonal appearance and growth of a hole over Antarctica
Ozone layer is destroyed by chlorofluorocarbons (CFC’s) used as coolants in refrigerators, air conditioners and some aerosol sprays
Banned in Canada in the late 1970’s
Use of CFC’s worldwide has declined once the danger to the ozone was recognized
When CFC’s rise in the atmosphere winds carry them to the polar regions
The polar vortex in Antarctica keeps air from mixing allowing CFC’s to combine with ice crystals to release chlorine which in turn destroys the ozone
When the vortex weakens in the summer the ozone is replenished
Northern hemisphere ozone has depleted by about 10%
Potential effects include increased skin cancer, wrinkling and aging of the skin, cataracts and blindness and a reduced immune response
Ozone Layer may interfere with photosynthesis and cause lower crop yields
May also kill phytoplankton and krill
Heat generated may cause changes in the stratospheric winds
The ozone layer is not expected to be “repaired” until 2070
2017 NASA reported the hole is the smallest since 1988
Shrinkage due more to natural variability rather than human activity
Environmental Threats of Extreme Energy Sources
Extreme energy sources – fossil fuels that are hard to access
Deep water oil rigs, tar sands and fracking are examples
Pipelines across wildlife habitats to shipping terminals on the coast
Fracking uses pressurized mixes of fluids to create cracks in the rock releasing natural gas
Several first nation communities have protested the exploration on native lands
Renewable energy
Are sources that are naturally replenished e.g. wind and sunlight, wave and geothermal
Sustainable development means meeting the needs of the society today without compromising the ability of future generations to meet their needs
Renewable resources
Wind power – energy of the wind to turn turbine blades
Solar power – photo energy is converted to electrical energy
Geothermal power taps the heat in the earth’s core
Hydroelectricity is produced when flowing water is used to turn the blades of a turbine
Biomasses plant material including trees when burned produce energy.
Plants are produced and harvested sustainably are considered a renewable source of energy
Biofuels are those fuels based on natural materials either alcohol or oil
Canada is recognized as a global leader in the production and use of renewable energy
Indoor Air Quality
Your home may harbor potentially dangerous pollutants some of which have been linked to cancer:
- Environmental tobacco smoke
- Carbon monoxide and other combustion by-products
- Volatile organic compounds
- Biological pollutants
- Indoor mould
Preventing Air Pollution
Cut back on driving
Keep your car tuned up and well maintained
Buy energy efficient appliances and use them only as necessary
Replace incandescent bulbs with LED and compact fluorescent bulbs
Make sure your home is well insulated with ozone safe agents
Plant and care for trees in your own yard and neighborhood
Check with waste haulers or local and government before disposing of refrigerators air conditioners or humidifiers
Keep your house adequately ventilated
Keep paints cleaning agents and other chemical products tightly sealed in their original containers
Don’t smoke and don’t allow others to smoke in your room apartment or home
Clean and inspect chimneys furnaces and other appliances regularly
Water Contamination and Treatment
Most cities rely in part by wells that tap local groundwater, but may be necessary to tap lakes and rivers to supplement water demand
Surface water is most likely to be contaminated and therefore must be purified before piped into the community
——The water is subjected to various physical and chemical processes
——Fluoridation has been used to reduce tooth decay by 25% for the last 75 years
Although most areas of Canada have dependable, clean water sources, many Indigenous communities do not
——-As of January 2022, 39 long-term water advisories were in effect in First Nations communities