Global Climate Change

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1 Global Climate Change Objective Infer how human activities (including population growth, pollution, global warming, burning of fossil fuels, habitat destruction, and introduction of non-native species) may impact the environment.

2 Climate Climate refers to long-term weather patterns for a particular area

3 Ecosystems Climate determines the types of vegetation that can survive in an ecosystem, which in turn, determines the types of animals.

4 Greenhouse Effect Light waves pass through the glass in a greenhouse, turn into infra-red heat waves that cannot escape.

5 Greenhouse Effect In Earth s atmosphere, water vapor and carbon dioxide, act as greenhouse gases in that they trap heat in Earth s atmosphere.

6 Carbon Cycle Carbon dioxide, CO 2, is removed from the atmosphere through photosynthesis. Organic waste, rich in carbon, that is not decomposed is buried and converted into fossil fuel.

7 Human Impact on Carbon Cycle Burning fossil fuels, during combustion, releases large amounts of carbon dioxide, CO 2, into the atmosphere. Decrease in photosynthesis from deforestation not only decreases the amount of CO 2 removed from the atmosphere, it also decreases the amount of stored CO 2. Slash and burn deforestation also releases large amounts of CO 2 into the atmosphere.

8 Carbon Dioxide Residence Time After 100 years, only 50% of any carbon dioxide is removed from the atmosphere. After 200 years, only 25% is removed from the atmosphere. 1 gallon of gas = 6 lbs CO2 1 year = 15,000 miles 20 miles /gallon = 7.5 tons CO2

9 Increased Levels of CO 2 in the Atmosphere The first recorded measurements of atmospheric carbon dioxide, back in 1955, was 315 ppm. Charles David Keeling PPM = 1 carbon dioxide molecule 1,000,000 air molecules ppm

10 Increased Levels of CO 2 in the Atmosphere Measurements of earlier atmosphere concentrations, using ice cores, confirmed that carbon dioxide levels had been increasing since the advent of the industrial revolution.

11 Increased Levels of CO 2 in the Atmosphere At the same time, there has also been an increase in the average global temperature since the industrial revolution.

12 Sources of CO 2 in the Atmosphere Currently, China emits the most carbon dioxide, followed by the United States. In the United States, most carbon dioxide emissions come from the burning of coal for the generation of electricity followed by transportation.

13 Evidence of Climate Change The ice cap in Kilimanjaro is 85% smaller than it was in It is believed the ice cap will be gone within 10 years.

14 Evidence of Climate Change Since 1998, the ice lost from just one of the five ice shelves in the study of Antarctica totals more than 1,500 square miles, an area larger than the state of Rhode Island.

15 Evidence of Climate Change Ice sheets in Greenland are also melting. The arctic ice at the North Pole continues to have record low ice thickness

16 Evidence of Climate Change The permafrost in the Tundra is melting making the ground and buildings unstable.

17 Evidence of Climate Change Sea level has already risen 6 8 inches during the past century. This historical rate of rise was greater than any other persistent, century-scale trend during the past 2,100 years.

18 Evidence of Climate Change Seasons have changed by a week during the past 50 years. Spring occurs a week earlier and fall begins a week later. Lilac festival in Massachusetts which used to be held at the end of May is now held in the beginning of May

19 Impacts of Climate Change At the rate the ice sheets are melting, sea level could rise anywhere between 3 meters and 16 meters, within the next couple of hundred years, displacing millions of people. Most major cities, around the world, are situated along the coast.

20 Impacts of Climate Change Many island nations are near sea level. These islands may be completely underwater with even a small rise in sea level.

21 Impacts of Climate Change Increased levels of CO 2 are being absorbed by ocean waters resulting in a change in ocean ph levels leading to ocean acidification. Lower ph levels in the ocean inhibits shell growth in marine animals and can cause reproductive disorders in fish.

22 Impacts of Climate Change Increased ocean temperatures also leads to more coral bleaching events.

23 Extreme Weather Extreme weather events such as large storms and heat waves will be more frequent and more intense.

24 Impacts of Climate Change Changes in the climate may cause some species to go extinct as the seasonal changes affect migration patterns, length of hunting seasons, or changes in habitat.

25 Impacts of Climate Change Mosquito-borne illnesses will increase in range. Malaria West Nile Virus Dengue Fever Zika Virus

26 Global Climate Change Burning of fossil fuels and deforestation, since the industrial revolution, have led to increased levels of CO 2 in the atmosphere. CO 2 is a greenhouse gas that traps infra-red heat waves causing a warming effect China and the United States emit the most CO 2 Evidence for climate change includes: warmer average temperatures; melting ice caps, ice shelves, sea ice, and permafrost; change in seasons. Impacts include rising sea levels; ocean acidification; ocean warming; increase in extreme weather; extinction of some species; and increase in the range of mosquito-borne diseases.