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Global warming

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Global warming is defined as the increase in average surface temperatures on Earth over the past century due to greenhouse gas emissions. The main causes are the greenhouse effect trapping heat from the sun and human activities increasing greenhouse gases in the atmosphere. Effects include more extreme weather, rising sea levels, and disrupted ecosystems. While some nations have taken steps to reduce emissions, current trends show temperatures and impacts continuing to increase without serious global action on solutions to mitigate further warming and help societies adapt.

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GLOBAL WARMING Presented by: Rashed Minhaz
Outline • Global warming: Definition. • Facts and Causes. • Effects. • Current situation. • Solutions. • Conclusion.
Global warming • Global warming: The phenomenon of increasing average air temperatures near the surface of Earth over the past one to two centuries and its related effects. Multiple lines of scientific evidence show that the climate system is warming.[Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid-19th century, and in paleoclimate proxy records covering thousands of years
Climate change • Global warming causes climate change. Not only climate become chaotics but also natural disasters occur frequently. Climate change deniers have argued that there has been a “pause” or a “slowdown” in rising global temperatures, but several recent studies, including a 2015 Paper published in the journal Science, have disproved this claim. And scientists say that unless we curb global-warming emissions, average temperatures could increase by up to 10 degrees Fahrenheit over the next century.
Causes of global warming • GREEN HOUSE EFFECT :The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in a planet's atmosphere warm its lower atmosphere and surface. On Earth, an atmosphere containing naturally occurring amounts of greenhouse gases causes air temperature near the surface to be about 33 °C (59 °F) warmer than it would be in their absence. Without the Earth's atmosphere, the Earth's average temperature would be well below the freezing temperature of water. The major greenhouse gases are water vapour , which causes about 36–70% of the greenhouse effect; carbon dioxaide(CO2), which causes 9–26%; methane (CH4), which causes 4–9%; and ozone (O3), which causes 3–7%. Clouds also affect the radiation balance through cloud forcings similar to greenhouse gases. Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere
Causes of global warming • Global warming occurs when carbon dioxide and other air pollutants and greenhouse gasses collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earth’s surface. Normally, this radiation would escape into space—but these pollutants, which can last for years to centuries in the atmosphere, trap the heat and cause the planet to get hotter. That's what's known as the greenhouse effect. It is the main cause of global warming.
Causes of global warming • Aerosols and soot: Global dimming, a gradual reduction in the amount of global direct irradiance at the Earth's surface, was observed from 1961 until at least 1990. Solid and liquid particles known as aerosols, produced by volcanoes and human-made pollutants, are thought to be the main cause of this dimming. • Solar activity: Since 1978, solar irradiance has been measured by satellites. These measurements indicate that the Sun's radiative output has not increased since then, so the warming that occurred in the past 40 years cannot be attributed to an increase in solar energy reaching the Earth. • Variations in Earth's orbit: The tilt of the Earth’s axis and the shape of its orbit around the Sun vary slowly over tens of thousands of years. This changes climate by changing the seasonal and latitudinal distribution of incoming solar energy at Earth's surface.
Effects of Global warming • Scientists agree that the earth’s rising temperatures are fueling longer and hotter heat waves, more frequent droughts, heavier rainfall, and more powerful hurricanes. The earth’s ocean temperatures are getting warmer, too—which means that tropical storms can pick up more energy. So global warming could turn a category 3 storm into a more dangerous category 4 storm. In fact, scientists have found that the frequency of North Atlantic hurricanes has increased as well as the number of storms that reach categories 4 and 5. The impacts of global warming are being felt across the globe. Extreme heat waves have caused tens of thousands of deaths around the world in recent years. And in an alarming sign of events to come, Antarctica has been losing about 134 billion metric tons of ice per year since 2002. This rate could speed up if we keep burning fossil fuels at our current pace, some experts say, causing sea levels to rise several meters over the next 50 to 150 years.
Effects of Global warming Each year, scientists learn more about the consequences of global warming, and many agree that environmental, economic, and health consequences are likely to occur if current trends continue. Some of these possible effects are: • Melting glaciers, early snowmelt, and severe droughts will cause more dramatic water shortages and increase the risk of wildfires. • Rising sea levels will lead to coastal flooding. • Forests, farms, and cities will face troublesome new pests, heat waves, heavy downpours, and increased flooding. All those factors will damage or destroy agriculture and fisheries • Disruption of habitats such as coral reefs and Alpine meadows could drive many plant and animal species to extinction. • Allergies, asthma, and infectious disease outbreaks will become more common due to increased growth of pollen-producing ragweed, higher levels of air pollution, and the spread of conditions favorable to pathogens and mosquitoes.
Current Situation • The current weather situation can be described in the following graph.
Current Situation • In recent years, China has taken the lead in global- warming pollution, producing about 28 % of all carbon dioxide emissions. The United States comes in second. News articles like “Change will continue through this century and beyond”, “Temperatures will continue to rise”, “Frost-free season (and growing season) will lengthen”, “Changes in precipitation patterns”, “More droughts and heat waves”, “Hurricanes will become stronger and more intense”, “Sea level will rise 1-4 feet by 2100” are common.This is also a fact that the current situation are going to lead us to a disasterous situation.
Solutions • Because we are already committed to some level of climate change, responding to climate change involves a two- pronged approach: • Reducing emissions of and stabilizing the levels of heat- trapping greenhouse gases in the atmosphere (“mitigation”).It can be done by either either by reducing sources of these gases or enhancing the sinks that accumulate and store these gases. • Adapting to the climate change already in the pipeline (“adaptation”). The goal is to reduce our vulnerability to the harmful effects of climate change. It also encompasses making the most of any potential beneficial opportunities associated with climate change
Solutions • Government policies are major factor in this regard. Because some head of the nations does not care about the global warming. They call it a hoax.They are the greatest obstacle for the climate activitists. Most countries in the world are parties to the United Nations Framework Convention on Climate Change(UNFCCC). The ultimate objective of the Convention is to prevent dangerous human interference of the climate system. As stated in the Convention, this requires that GHG concentrations are stabilized in the atmosphere at a level where ecosystems can adapt naturally to climate change, food production is not threatened, and economic development can proceed in a sustainable fashion.The Framework Convention was agreed in 1992, but since then, global emissions have risen. If the world leaders can not come to an solution, the anti-climate activity can not be stopped also the the activity to protect the world from global warming will be hindered.Before China was against the activity but now they agree with the situation. On the otherhand the present president of America tells that all of these are hoax.
Conclusion • Global warming will effect the world as a whole. It is just that some will suffer more and some will less. The future will become unhabitable due to this. It is not wise to not take necessary steps to prevent global warming even knowing the situation that the global warming will bring. Some necessary steps may save us from the catastrophe that global warming can possibly cause. As we know prevention is better than cure.
Global warming

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Global warming

  • 2. Outline • Global warming: Definition. • Facts and Causes. • Effects. • Current situation. • Solutions. • Conclusion.
  • 3. Global warming • Global warming: The phenomenon of increasing average air temperatures near the surface of Earth over the past one to two centuries and its related effects. Multiple lines of scientific evidence show that the climate system is warming.[Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid-19th century, and in paleoclimate proxy records covering thousands of years
  • 4. Climate change • Global warming causes climate change. Not only climate become chaotics but also natural disasters occur frequently. Climate change deniers have argued that there has been a “pause” or a “slowdown” in rising global temperatures, but several recent studies, including a 2015 Paper published in the journal Science, have disproved this claim. And scientists say that unless we curb global-warming emissions, average temperatures could increase by up to 10 degrees Fahrenheit over the next century.
  • 5. Causes of global warming • GREEN HOUSE EFFECT :The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in a planet's atmosphere warm its lower atmosphere and surface. On Earth, an atmosphere containing naturally occurring amounts of greenhouse gases causes air temperature near the surface to be about 33 °C (59 °F) warmer than it would be in their absence. Without the Earth's atmosphere, the Earth's average temperature would be well below the freezing temperature of water. The major greenhouse gases are water vapour , which causes about 36–70% of the greenhouse effect; carbon dioxaide(CO2), which causes 9–26%; methane (CH4), which causes 4–9%; and ozone (O3), which causes 3–7%. Clouds also affect the radiation balance through cloud forcings similar to greenhouse gases. Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere
  • 6. Causes of global warming • Global warming occurs when carbon dioxide and other air pollutants and greenhouse gasses collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earth’s surface. Normally, this radiation would escape into space—but these pollutants, which can last for years to centuries in the atmosphere, trap the heat and cause the planet to get hotter. That's what's known as the greenhouse effect. It is the main cause of global warming.
  • 7. Causes of global warming • Aerosols and soot: Global dimming, a gradual reduction in the amount of global direct irradiance at the Earth's surface, was observed from 1961 until at least 1990. Solid and liquid particles known as aerosols, produced by volcanoes and human-made pollutants, are thought to be the main cause of this dimming. • Solar activity: Since 1978, solar irradiance has been measured by satellites. These measurements indicate that the Sun's radiative output has not increased since then, so the warming that occurred in the past 40 years cannot be attributed to an increase in solar energy reaching the Earth. • Variations in Earth's orbit: The tilt of the Earth’s axis and the shape of its orbit around the Sun vary slowly over tens of thousands of years. This changes climate by changing the seasonal and latitudinal distribution of incoming solar energy at Earth's surface.
  • 8. Effects of Global warming • Scientists agree that the earth’s rising temperatures are fueling longer and hotter heat waves, more frequent droughts, heavier rainfall, and more powerful hurricanes. The earth’s ocean temperatures are getting warmer, too—which means that tropical storms can pick up more energy. So global warming could turn a category 3 storm into a more dangerous category 4 storm. In fact, scientists have found that the frequency of North Atlantic hurricanes has increased as well as the number of storms that reach categories 4 and 5. The impacts of global warming are being felt across the globe. Extreme heat waves have caused tens of thousands of deaths around the world in recent years. And in an alarming sign of events to come, Antarctica has been losing about 134 billion metric tons of ice per year since 2002. This rate could speed up if we keep burning fossil fuels at our current pace, some experts say, causing sea levels to rise several meters over the next 50 to 150 years.
  • 9. Effects of Global warming Each year, scientists learn more about the consequences of global warming, and many agree that environmental, economic, and health consequences are likely to occur if current trends continue. Some of these possible effects are: • Melting glaciers, early snowmelt, and severe droughts will cause more dramatic water shortages and increase the risk of wildfires. • Rising sea levels will lead to coastal flooding. • Forests, farms, and cities will face troublesome new pests, heat waves, heavy downpours, and increased flooding. All those factors will damage or destroy agriculture and fisheries • Disruption of habitats such as coral reefs and Alpine meadows could drive many plant and animal species to extinction. • Allergies, asthma, and infectious disease outbreaks will become more common due to increased growth of pollen-producing ragweed, higher levels of air pollution, and the spread of conditions favorable to pathogens and mosquitoes.
  • 10. Current Situation • The current weather situation can be described in the following graph.
  • 11. Current Situation • In recent years, China has taken the lead in global- warming pollution, producing about 28 % of all carbon dioxide emissions. The United States comes in second. News articles like “Change will continue through this century and beyond”, “Temperatures will continue to rise”, “Frost-free season (and growing season) will lengthen”, “Changes in precipitation patterns”, “More droughts and heat waves”, “Hurricanes will become stronger and more intense”, “Sea level will rise 1-4 feet by 2100” are common.This is also a fact that the current situation are going to lead us to a disasterous situation.
  • 12. Solutions • Because we are already committed to some level of climate change, responding to climate change involves a two- pronged approach: • Reducing emissions of and stabilizing the levels of heat- trapping greenhouse gases in the atmosphere (“mitigation”).It can be done by either either by reducing sources of these gases or enhancing the sinks that accumulate and store these gases. • Adapting to the climate change already in the pipeline (“adaptation”). The goal is to reduce our vulnerability to the harmful effects of climate change. It also encompasses making the most of any potential beneficial opportunities associated with climate change
  • 13. Solutions • Government policies are major factor in this regard. Because some head of the nations does not care about the global warming. They call it a hoax.They are the greatest obstacle for the climate activitists. Most countries in the world are parties to the United Nations Framework Convention on Climate Change(UNFCCC). The ultimate objective of the Convention is to prevent dangerous human interference of the climate system. As stated in the Convention, this requires that GHG concentrations are stabilized in the atmosphere at a level where ecosystems can adapt naturally to climate change, food production is not threatened, and economic development can proceed in a sustainable fashion.The Framework Convention was agreed in 1992, but since then, global emissions have risen. If the world leaders can not come to an solution, the anti-climate activity can not be stopped also the the activity to protect the world from global warming will be hindered.Before China was against the activity but now they agree with the situation. On the otherhand the present president of America tells that all of these are hoax.
  • 14. Conclusion • Global warming will effect the world as a whole. It is just that some will suffer more and some will less. The future will become unhabitable due to this. It is not wise to not take necessary steps to prevent global warming even knowing the situation that the global warming will bring. Some necessary steps may save us from the catastrophe that global warming can possibly cause. As we know prevention is better than cure.