Presentation on theme: "Climate Change An Inconvenient Truth. MAIN IDEAS 1.Human use of resources is releasing increasing amounts of CO 2 into the atmosphere. 2.This is leading."— Presentation transcript:
Climate Change An Inconvenient Truth
MAIN IDEAS 1.Human use of resources is releasing increasing amounts of CO 2 into the atmosphere. 2.This is leading to an increase in temperature. 3.Increasing temperatures are changing our environment in ways that are & will increasingly be harmful to earth and its people. 4.It is the responsibility of government & individuals to improve our situation by their actions. It is both a political and moral imperative.
SUPPORT 1.THE GREENHOUSE EFFECT Greenhouse Gases: chemical compounds in the atmosphere that trap heat they retain a proportion of the sun’s heat through the greenhouse effect. 5 major greenhouse gases: Gas% of Greenhouse Effect water vapour (H 2 O) 36-70% carbon dioxide (CO 2 )9-26% methane (CH 4 )4-9% ozone (O 3 )3-7% nitrous oxide (N 2 0)2-6%
CAUSES OF GH EFFECT: Human Activities: causing an increase of the amount of greenhouse gases in atmosphere, such as: burning natural gas, coal and oil (including gasoline for engines) raises the level of carbon dioxide in the atmosphere. some farming practices and land-use changes increase the levels of CH 4, N 2 O & CO 2 factories produce long-lasting industrial gases that do not occur naturally deforestation - trees use CO 2 and give off O 2 in its place, so there are fewer trees to perform this critical function.
population growth - more people use fossil fuels for heat, transportation and manufacturing, more farming occurs to feed millions of new people more greenhouse gases means more infrared radiation trapped and held, which gradually increases the temperature of the Earth's surface and the air in the lower atmosphere. CO 2 concentrations have increased from about 313 ppm (parts per million) in 1960 to about 383 ppm in 2009
2. CO 2 INCREASING IN ATMOSPHERE 1. What does this graph show? 2. Why does it go up and down each year? 3. What is it’s consistent trend? 4. What is the connection between this and rising temperatures?
3. GLACIERS MELTING 1.Why do permanent ice areas exists? 2.What does Gore show happening in Kilimanjaro, Glacier National Park, Italian Alps, & South America? 3.Why is this a problem, particularly with the Himalayas.
4. What cyclical pattern does this show? 5. What connection does it show between carbon dioxide levels and temperature? 6. Why might this weaken Gore’s argument? 7. Why does Gore imply that it does not weaken it?
4. CHANGES TO OCEANS Ocean Levels: glaciers & ice caps consist of frozen fresh water fresh water melts into the oceans can cause water levels to rise ocean levels have risen by: 1.8 mm/yr in past century mm/yr since 1993
Antarctic ice contains 70% of world fresh water if melted, levels would rise by 61 m avg temp in Antarctic is -37 o C = unlikely Greenland closer to equator, melting already seen 2009 showed record lack of sea ice in Arctic if all melted, levels would rise by 7 m estimated by 2100 levels will rise by 50 cm (lowest 15 cm – highest 95 cm)
Ocean Currents: currents driven by differences in density between salt and fresh water salt water falls to bottom, fresh rises this pulls warm tropical water from equator to replace ‘falling’ water (warm current) cold current flows south along bottom ‘drives’ Ocean Conveyor and moves currents around earth
as more fresh water added it changes the current for last 15 years, sinking has been absent or too shallow to drive the Ocean Conveyor implications??
Climate Changes Impacts in Canada Environmental Impacts: warmer winters; tree line and wildlife species shift to the north; more frequent heat waves; changes in general weather patterns (precipitation, winds, and temperature); permafrost melting in the arctic; increased frequency of storms; glaciers retreating; greater risk of icebergs off the coast of Labrador; arctic sea ice melting changes to Inuit way of life and opening up year round ice free shipping routes; sea levels rising; more severe drought conditions in the Prairies and B.C. leading to a loss of crops and forest wildfires; and
Political Impacts: displaced populations/immigration demand for water resources Northwest Passage opening – route for oil tankers, toxic wastes? oil/gas resources under ice? Arctic sovereignty