Chp 16 CLIMATE CHANGE

 Climate change refers to the changes average weather patterns.  More or less rain then normal in some areas, more or less wind, hotter or colder temperatures. All of these things are climate change.  Global warming on the other hand is the raising of the average temperature on earth by having gases like CO 2 absorb heat and trap it like a blanket around the earth. What is Climate Change 16.1 VOCABULARY Climate Change Global Warming Enhanced Greenhouse Effect Carbon Dioxide Equivalent Carbon sinks Ozone layer Permafrost

 The main way that global warming works is though the greenhouse effect. This effect traps heat close to the earth and holds it there by heating up greenhouse gases (GHGs) the same way that the glass in a greenhouse holds heat in. The greenhouse effect is needed on earth, without it the average temperature on earth would be about -18 o C. The thing that is dangerous is the enhanced greenhouse effect. This is when the air is heated too much and weird weather starts to happen. Greenhouse Effect VOCABULARY Climate Change Global Warming Enhanced Greenhouse Effect Carbon Dioxide Equivalent Carbon sinks Ozone layer Permafrost 16.1

 There are a many GHGs, the main ones are: a. Water vapour b. CO 2, carbon dioxide c. CH 4, methane (1 ton = 21 tons of CO 2 ) d. N 2 O, nitrous oxide (very little) e. CFCs, chlorofluorocarbons (1 ton = 10,000 tons CO 2 )  Even though it has the least heating affect CO 2 is the worst GHG because there is just so much of it. Anything that produces CO 2 is called a carbon source and anything that absorbs CO 2 is called a sink What are Greenhouse Gases

 The ozone layer is another aspect of climate change. It is the layer of ozone gas (O 3 ) in the atmosphere that absorbs cancer causing UV rays. It has thinned out because of the presence of CFCs in the atmosphere. While it is good that it absorbs UV light it is a part of enhanced global warming because it also absorbs a lot of heat further heating the air in the atmosphere.  Evidence of climate change includes direct evidence that can be measured and indirect evidence that implies there is a change going on. Ozone Layer VOCABULARY Climate Change Global Warming Enhanced Greenhouse Effect Carbon Dioxide Equivalent Carbon sinks Ozone layer Permafrost 16.1

a. Direct i. Atmospheric CO 2 levels are rising ii. Average global temperature is rising iii. Glaciers and Ice sheets that used to last year round are shrinking iv. Permafrost is melting and mudslides are happening. v. Sea levels are rising vi. The sea ice in the arctic is melting VOCABULARY Climate Change Global Warming Enhanced Greenhouse Effect Carbon Dioxide Equivalent Carbon sinks Ozone layer Permafrost 16.1 Evidence of Climate Change

a. Indirect i. Tree rings ii. Ice cores iii. Sediments iv. Coral rings VOCABULARY Climate Change Global Warming Enhanced Greenhouse Effect Carbon Dioxide Equivalent Carbon sinks Ozone layer Permafrost 16.1 Evidence of Climate Change

 While there is not complete agreement among scientists the following things are not disputed: a. The Earth is 0.6 o C warmer now than it was in O.51 o C of that happened since b. Human activities do contribute to climate change and global warming. c. GHG emissions likely speed up global warming. d. Global warming is a problem and we should do something about it VOCABULARY Climate Change Global Warming Enhanced Greenhouse Effect Carbon Dioxide Equivalent Carbon sinks Ozone layer Permafrost Evidence of Climate Change

 There are two kinds of influences on climate on earth.  natural  human caused. Influences on Climate Change and Climate VOCABULARY El Nino Thermocline La Nina 16.2

i. El Nino is when the ocean currents go reversed to what is normal for them. This causes moist wet low pressure zones over South Americas and brings rain while causing drought in Indonesia and North America. It causes our winters to be milder as well. ii. La Nina is the opposite of El Nino. It brings colder and wetter than normal winters. iii. Volcanic Eruptions cause large amounts of SO 2 to go into the air. This absorbs heat. The eruption of Mount Pinatubo in 1991 cooled the earth by about 0.8 o C for 1 year. VOCABULARY El Nino Thermocline La Nina Natural Influences 16.2

i. Combustion of fossil fuels puts carbon that has been stored for millions of years back into the atmosphere. ii. Deforestation for the sake of agriculture is causing use to lose a major carbon sink. We need to grow our forests faster than we cut them down to absorb CO 2. iii. Industry releases tones of CO 2 every year to make us products to buy. Many power stations also emit CO 2 gas. iv. Waste Disposal the rotting or decaying of organic waste releases methane which is a GHG. VOCABULARY El Nino Thermocline La Nina Human Influences 16.2

Potential Impact of Climate Change 16.3

Impacts of Global Warming 16.3  Weather Changes  Impacts on Forests  Impact on Animals  Impact on Canada’s Northern Regions  Impacts on Human Health Saftey  Impacts on Sea Level