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1. geography 4B CHAN CHO YAU (3) 4E WAI SIU HANG YIP WING KWAN S.4

2. CATALOGUE What is global warming Evidence of global warming Cause of global warming Greenhouse effect Consequences Solutions

3. What is global warming? • Global warming is the increase in the average temperatureof Earth's near-surface air and oceans since the mid-20th century and its projected continuation. According to the 2007 Fourth Assessment Report by the Intergovernmental Panel on Climate Change(IPCC), global surface temperature increased by 0.74 ± 0.18 °C(1.33 ± 0.32 °F) during the 20th century.

4. Evidence of global warming • Graph of Historical Trend of Warming Temperatures • Carbon Dioxide Increasing in Atmosphere • Methane Also Increasing • More Frequent Extreme Weather • Disappearing Glaciers • Melting Arctic Sea Ice • Melting Antarctic Sea Ice • Greenland's Ice Sheet Melting • Tropical Diseases Spreading • Oceans Warming With Coral Bleaching & Disintegration

5. Carbon Dioxide Increasing in Atmosphere • The atmospheric levels of the greenhouse gas carbon dioxide, have increased since pre-industrial times from 280 part per million (ppm) to 377.5 ppm (2004 Carbon Dioxide Information Analysis Center), a 34% increase.

6. Methane Also Increasing • Levels of atmospheric methane, a powerful greenhouse gas, have risen 145% in the last 100 years. Methane is derived from sources such as rice paddies, bovine flatulence, bacteria in bogs and fossil fuel production.

7. More Frequent Extreme Weather • "The potential for floods and droughts is increasing."....... the heating from increased greenhouse gases enhances the hydrological cycle and increases the risk for stronger, longer-lasting or more intense droughts, and heavier rainfall events and flooding, even if these phenomena occur for natural reasons. Evidence, although circumstantial, is widespread across the United States. says Dr. Kevin Trenberth of the National Oceanic and Atmospheric Administration (NOAA).

8. Disappearing Glaciers • Disappearing Glaciers Ice is melting all over the planet. Glaciers are melting on six continents. • If present warming trends continue, all glaciers in Glacier National Park could be gone by 2030. The park's Grinnell Glacier is already 90% gone. • Because of global warming, the glaciers of the Ruwenzori range in Uganda are in massive retreat. • The Bering Glacier, North America's largest glacier, has lost 7 miles of its length, while losing 20-25% of parts of the glacier. • Ice cores taken from the Dunde Ice Cap in the Qilian Mountains on the northeastern margin of the Qinghai-Tibetan Plateau indicate that the years since 1938 have been the warmest in the last 12,000 years. • The melting is accelerating. The Lewis Glacier on Mt. Kenya (In Kenya) has lost 40% of its mass during the period 1963-1987 or at a much faster clip than during 1899-1963.

9. Melting Arctic and Antarctic Sea Ice • The Arctic, with an area about the size of the United States, is seeing average temperatures similar to the Antarctic, almost 5 degrees Fahrenheit warmer than the planet as a whole Arctic sea ice has shrunk by 250 million acres -- an area the size of California, Maryland and Texas combined.

10. Greenland's Ice Sheet Melting • In a recent study by researchers from NASA's Goddard Space Flight Center shows that Greenland's ice sheet, about 8% of the Earth's grounded ice (Antarctica possessing 91% of land ice), is losing ice mass. A NASA high-tech aerial survey shows that more than 11 cubic miles of ice is melting along Greenland's coasts yearly, accounting for 7% of the annual global sea level rise. Measurements over the last century suggest that sea level has risen 9 inches, enough to cause flooding in low-lying areas, when a storm occurs. Sea level increase could worsen, if the present trend continues, says William Krabill, lead author of the NASA study

11. Tropical Diseases Spreading • A recent study by New Zealand doctors, researchers at the Wellington School of Medicine's public health department said outbreaks o f dengue fever in South Pacific islands are directly related to global warming. Global warming is projected to significantly increase the range conducive to the transmission of both dengue and yellow fevers. 

12. Cause of global warming • The temperature is increased because by increasing concentrations of greenhouse gases, which result from human activities such as the burning of fossil fuel and deforestation. • Global dimming, a reduction of sunlight reaching the surface as a result of increasing atmospheric concentrations of human-made particulates, has partially countered the effects of warming induced by greenhouse gases.

13. Greenhouse effect • The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in the atmosphere warm a planet's lower atmosphere and surface. • CO2 is the principal greenhouse gas in terms of the greenhouse effect. • Currently in the world 40% of all CO2 emissions are caused by power plants. These are burning coal, natural gas and diesel fuel.

14. Consequences • Global Warming effects • global warming is going to have some effect on Earth. Here are the 5 deadliest effects of global warming.

15. 1. Spread of disease • As northern countries warm, disease carrying insects migrate north, bringing plague and disease with them. Indeed some scientists believe that in some countries, thanks to global warming, malaria has not been fully eradicated.

16. 2. Warmer waters and more hurricanes • As the temperature of oceans rises, so will the probability of more frequent and stronger hurricanes. We saw in this in 2004 and 2005.

17. 3. Increased probability and intensity of droughts and heat waves • Although some areas of Earth will become wetter due to global warming, other areas will suffer serious droughts and heat waves. Africa will receive the worst of it, with more severe droughts also expected in Europe. Water is already a dangerously rare commodity in Africa, and according to the Intergovernmental Panel on Climate Change, global warming will exacerbate the conditions and could lead to conflicts and war.

18. 4. 4.Economic consequences • Most of the effects of anthropogenic global warming won’t be good. And these effects spell one thing for the countries of the world: economic consequences. Hurricanes cause billions of dollars in damage, diseases cost money to treat and control and conflicts exacerbate all of these.

19. 5.Destructive storms • With ocean temperature being a key factor for hurricane formation, the consequences of global warming will inevitably include the increased generation of storms and hurricanes with greater power and frequency. • The destructive power of hurricanes has increased by some 50% in the last 30 years, a figure that is closely connected with the rising temperature of the ocean. Warmer water leads to greater evaporation, which in turn helps to not just ‘prime’ the coalescence of hurricanes and cyclones but also to maintain their vigour once extant. • Simply put, warmer oceans make for more extreme weather including devastating storms.

20. Solutions • Who can reduce global warming emissions? We can—together. Our individual efforts are important, but the biggest impact on climate change will come from large-scale changes—well-reasoned international policies; thoughtful, systematic efforts to reduce polluting fossil fuel energy sources and unsound land use practices; and steady progress toward a green, sustainable future.

21. Solutions • The solutions of Global warming, 1, To restrict the cars emission level, that is what europe doing.2, Use any other energy besides coal burning method, in order to reduce the CO2 emission.3, Plant more plant, due to plant can absorb CO2 and release O2 during daytime. 4, Stop the deforestation. 5. Increasing energy efficiency

22. Solutions 6.Modifying the CO2 balance as a result of geo or planetary engineering 7.Climate engineering proposals involving the reflection of incoming solar radiation 8.Climate engineering proposals involving removal of CO2 from the air by enhancing natural sinks

23. Summary • What can we do for it?you may think the power you have is too tiny to change.However ,it can be enlarged if anyone do it.That very simple doing them in our daily life, etc taking public transport if time is allowed , avoiding overuse of air-conditioner Can you do,You are recommended to do more in other way . • All at all, it is amendable or not is depend on what the man do.It is nothing if everyone in this world ignore it.

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