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Global warming ppt

  1. GROUP MEMBERS • Hajira Amir. • Dilawaiz Fareed. • Qudsia Nadeem. • Rida Suleman . • Mahnoor Butt. • Maimoona Ikhtiar.
  3. Global Warming •Definition: A gradual increase in the temperature of the earth‘s atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants.
  4. History of Global Warming •When was the idea of global warming first introduced? •Svante Arrhenius (1859-1927)was a Swedish scientist he was the fist to claim in 1896 that fossile fuel combustion may eventually result in enhanced global warming.
  5. Continue…… •Arrhenius predicted both carbon dioxide level and temperature increased from 1900-1999. •Arrhenius published ‘Worlds in the Making’, in which he describes ‘hot- house theory’. •Hot-house theory is basically Green house effect.
  6. Pakistan and Global Warming •When was global warming first noticed in Pakistan? •Pakistan recorded one of the highest temperatures in the world – 53.5 °C (128.3 °F) – on 26 May 2010, the hottest temperature ever recorded in Pakistan.
  7. Natural causes  There are several events in the natural world that can contribute to global warming.  These natural events have been taking place for millions of years, way before mankind’s existence, and will continue to do so until the end of time. Some of them are:
  8. Forest Fire • Forest fires emit carbon- filled smoke into the atmosphere. • New forests’ growth is slow and not stable enough to produce the much needed oxygen.
  9. Permafrost •A thick subsurface layer of soil that remains below freezing point throughout the year, occurring chiefly in polar regions. •When frozen soil increases, it keeps in the carbon and methane gases. •As permafrost thaws , Carbon is released to the atmosphere in the form of methane. As
  10. Solar activity ~ Sunspots •A spot or patch that appears from time to time on the sun's surface, appearing dark by contrast with its surroundings. These are magnetic storms on the surface of the Sun. • Sunspots restrict the passing of solar plasma, which in affect gives off radiation. •They change the energy radiating to earth’s atmosphere, and thus increase climate temperature.
  11. Volcanic Eruption •It occurs when hot materials are thrown out of a volcano. Lava , dust and gas are some of these ‘ejecta’. •Terrible explosion that throw out huge amounts of rock and ash and Kill many people and destroys property . •They spew millions of pounds of CO2 into the atmosphere at one time when erupt .w •Release other green house gases like CH4, SO2, CO ,H2S and HCl.
  12. Man made causes  Processes in our daily lives are expelling chemicals and foreign substances into the air that affect and increase the natural greenhouse gases. This results in global warming and changes the climate .  Human activities contribute to climate change by causing changes in Earth's atmosphere in the amounts of greenhouse gases, aerosols (small particles), and cloudiness.
  13. Deforestation •Deforestation is the cutting down of trees and plants to make way for any development activity. •The loss of our forests results in release of much carbon into the air, with not enough oxygen to combat it. • With more CO2 in the atmosphere, more sun's radiation are being reflected back to earth.
  14. Burning of Fossil Fuels. •Each time a fossil fuel burn, CO2 levels in the atmosphere increase. •Coal is the major fuel that is burnt to produce power. Coal produces around 1.7 times carbon dioxide per unit of energy. •Auto mobiles, and other means of transportation release CO2. •Industries release various gases into the water and air. CO2, CH4, and N2O have different heat trapping capability.
  15. Mining activity •Mining oil, coal and other mineral products underlying in deep beds allow methane, a greenhouse gas, to escape from the earth. •Methane, like carbon dioxide creates a thick shield over the atmosphere trapping the sun’s rays. •Continued use of mining operations will only increase harmful gases .
  16. Fertilizer Use •Fertilizer is that it produces nitrous oxide once it absorbs the soil. •Nitrous oxide is 300 times more dangerous than carbon dioxide. •The EPA strongly warns that the farming industry’s use of fertilizer is one of the leading causes of global warming.
  17. Overpopulation • Since CO2 contributes to global warming, the increase in population makes the problem worse because we breathe out more CO2 in the atmosphere. •More people means more carbon dioxide in the atmosphere.
  18. • Sun’s energy passes through atmosphere. • 26% is reflected or scattered. • 19% absorbed by clouds ,gases, and particles. • 4% reflected to space by sun. • 51% reaches the surface
  19. • The green house effect is the effect of atmospheric gases. • Carbon dioxide absorbing energy from the sun and earth and trapping. • It near the earths surface ,warming the Earth to a temperature range that is hospitable for life.
  20. Car parked in sunlight: • Glass lets in light. • Glass keeps heat from escaping. • Cause the car to heat up.
  21. Green house gases are those that can absorb and emit infrared radiations. The primary green house gases in the Earth’s atmosphere are • Water vapor • Carbon dioxide • Methane • Nitrous Oxide • Ozone • Chlorofluorocarbons
  22. • Human activities are significantly increasing atmospheric conditions of many GHG’s. •The most significant GHG directly affected by anthropogenic activity, is the product of the oxidation of carbon in organic matter, either through combustion of carbon-based fuels or the decay of biomass. • Natural CO2 sources include volcanic eruptions, respiration of organic matter in natural ecosystems, natural fires, and exchange of dissolved CO2with the oceans.
  23. • Methane is produced by anaerobic decay of organic material in landfills, wetlands, and rice fields; enteric fermentation in the digestive tracts of ruminant animals such as cattle, goats, and sheep; manure management; • Wastewater treatment; fossil fuel combustion; and leaks from natural gas transportation and distribution systems and abandoned coal mines.
  24. • Nitrous oxide (N2O) is produced by fertilizer use, animal waste management, fossil fuel combustion, and industrial activities. • Hydrofluorocarbons and perfluorocarbons are synthetic chemicals that are used in a variety of industrial production processes such as semiconductor manufacturing. • HFCs and PFCs are replacing CFCs in applications such as refrigeration and foam-blowing for insulation.
  25. Impacts of Global Warming: On humans: • Climate change induced mortality • Certain types of weather events are affected. • Climate change affect human health • A changing climate affects population health clean air and water, sufficient food, infectious disease agents and security of shelter • A warmer and more variable climate leads to higher levels of some air pollutant.
  26. On Animals: • Penguins are at risk • Glaciers are receding at an alarming rate and changing the environment of the mountains • Polar ice is melting • Rise in water temperatures • Mammals come out of hibernation sooner • Polar bears disappearing • Plants moved to cooler areas
  27. On plants: • Due to rising temperatures, plants and trees are not growing properly. • The effect of global warming in plants is caused by land and water temperatures as a result surface and underwater plant life is harmed. • The plants of the mountain and Polar Regions are especially at harm. • Decrease amount of rain can cause droughts. • It could affect crop growth and quality, livestock health, and pests. • The sudden changes in temperature rise in majority of the seasons affects the amount of rainfall. This can seriously damage the growing of crop. .
  28. On Oceans: • Increased level of CO2 have led to ocean acidification. • Changes in Cryosphere. • Drowning wetlands. • Fish migration. • Coral bleaching.
  29. On buildings: • A higher solar intensity resulting in higher exterior and interstitial surface temperatures and for the exposed components, higher levels of UV and resultant damage. • Increased frequency and intensity of wind and flooding event • A milder climate will reduce the durability of building materials and affect the indoor climate of buildings
  30. Solution to global warming •For millions of years, the earth’s climate has naturally fluctuated, changing up from warmer periods to ice ages. • However, within the past century, the earth’s temperature has increased unusually fast; 1.2 to 1.5 degrees Fahrenheit to be exact. •According to research studies, human activities are hugely contributing to this unusual spike in temperatures.
  31. Reduce Emissions • We must significantly reduce the amount of heat- trapping emissions we are putting into the atmosphere. • As individuals, we can help by taking action to reduce our personal carbon emissions • Expand the use of renewable energy and transform our energy system to one that is cleaner
  32. Stop Deforestation • Tropical deforestation accounts for about 10 percent of the world’s heat-trapping emissions. • Reducing tropical deforestation can significantly lower global warming emissions from fossil fuels.
  33. Buy recycled products • Order or buy products that require less packaging to cut down on the amount of waste • If there is no recycling plant in your area, make a point to start one.
  34. Less driving • Minimal driving is tantamount to less emission. • Choosing healthy activities such as walking and riding a bicycle is a great way to cut back on atmospheric emissions. • These acts serve to minimize the number of cars on the road, hence, reducing the possibility of global warming.
  35. Keep devices and appliances switched off • When not using devices and appliances such as computers, laptops, ovens, television and so on, make sure they are switched off. • This act reduces the amount of energy expenditure by more than 40 percent.
  36. Be an energy conservation ambassador • Teach your friends, family, and neighbors about recycling and energy conservation. Take time to encourage public officials to initiate policies and programs that promote clean environment.
  37. Future predictions for global warming • Changing in precipitation • Rising sea level • Acidic ocean water • Impact on ocean currents
  38. Continue... • More clouds • Changes to life and the carbon cycle • Melting snow and ice • Changing severe weather