Understanding Global Warming

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Understanding Global Warming

• A Live Green, Live Smart Presentation

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The Greenhouse Effect

• To understand global warming, we must first
  understand the Greenhouse Effect.
• The Earths naturally mild temperature and
  climate is a result of the Greenhouse Effect.
• Gases in the atmosphere, like carbon dioxide
  (CO2), methane (CH4), and ozone (O3), cover the
  Earth like the glass walls of a greenhouse.
• These gases serve two purposes they protect the
  planet from receiving too much sunlight (and
  heat), and they trap sunlight to prevent it from
  escaping into space.
• Normally these two actions are balanced perfectly
  so the Earths climate is warm and livable.

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The Greenhouse Effect

• A rapid change in greenhouse gas concentration
  causes the system to become unbalanced.
• If the amount of greenhouse gas decreases, the
  Earth cools down, and can enter an Ice Age.
• If the amount increases, the Earth warms up -
  this is called Global Warming.
• If the Greenhouse Effect becomes too unbalanced
  in either direction, the Earth may become
  uninhabitable for humans.

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Humans and Global Warming

• Most scientists now believe the Earth is entering
  a period of global warming.
• Many also believe that human activities are
  causing the Earth to warm at an unnaturally rapid
  pace.

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How Are Humans Contributing to Global Warming?

• The primary human-related cause of global warming
  is the burning of fossil fuels like oil, coal,
  and natural gas.
• When fossil fuels are burned, they release carbon
  dioxide into the air, which collects in the
  atmosphere as a greenhouse gas.
• We use fossil fuels every day to power our cars,
  to light and heat (or cool) our homes, to
  manufacture goods, and to grow food.
• We have also put more methane, ozone, and other
  greenhouse gases into the atmosphere through
  industrial and agricultural production.

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How Are Humans Contributing to Global Warming?

• Carbon dioxide levels in the atmosphere have
  increased 30 since the start of the Industrial
  Revolution.
• Methane levels have increased 150.
• The result of this increase in greenhouse gas is
  that less of the sun's heat is able to escape
  through the atmosphere into space.
• This heat stays trapped in the Earths climate.
• As more greenhouse gases enter into the
  atmosphere, more of the suns heat is trapped
  and the Earth gets warmer and warmer.
• In the last century the planets average
  temperature rose 1.3?F.
• This may not seem like much, but we are already
  experiencing the effects of this increase.
• The difference in temperature between the last
  Ice Age and todays climate is only 5?F.

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When the Greenhouse Effect is altered so
drastically and so suddenly, the entire planet is
put in danger.
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Dangers of Global Warming

• Among the dangers posed to the climate by
  increasing temperatures are
• Disruption of the Carbon Cycle
• Changes in weather patterns, including more
  frequent severe storms, such as hurricanes
• Droughts and water shortages in some places
• Increased rainfall in others
• Rising ocean levels
• Vast, complex and often subtle changes are
  difficult to comprehend.
• If we look at these changes in more specific
  terms, the degree of devastation becomes plainer.
• The following slides are but a few examples of
  the effects of global warming on the climate.

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The Carbon Cycle

• Normally the planet has ways to deal with excess
  carbon in the atmosphere.
• Plants eat carbon dioxide and produce oxygen,
  which animals eat, producing carbon dioxide.
• This is called the Carbon Cycle.
• Trees and ocean algae do most of this eating.
• The amount of carbon dioxide in the atmosphere
  today has overloaded the Carbon Cycle it cannot
  keep up.
• Deforestation and pollution in the oceans have
  also helped to reduce the effectiveness of the
  Carbon Cycle.

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Changes in Weather

• Since 1980 weve had 22 of the warmest years on
  record.
• Six of the warmest have been within the last
  eight years.
• Storms and hurricanes in North America and the
  Atlantic Ocean have become more frequent and more
  violent.
• Fatal consecutive summer heat waves have beset
  Europe.
• Snow cover in the Northern Hemisphere has
  decreased 10 since 1966.
• The Arctic Summer melting season increased
  between 1979 and 1998 the shortest was 57 days
  in 1979 the longest, 81 days in 1998.

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Droughts

• According to the National Center for Atmospheric
  Research, Earth's dry, arid lands expanded from
  less than 15 of the total in the 1970s, to 30
  in 2002.
• In 2002, record temperatures brought about severe
  droughts, causing a worldwide harvest loss of 90
  million tons. In 2004 there was a loss of 34
  million tons due to drought caused by increased
  temperatures.
• A study from corn- and rice-producing countries
  noted a 17 drop in crop yields with just a 1.8?F
  temperature rise.

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Water shortages

• A study done by the United States Geological
  Survey showed that the number of glaciers in
  Glacier National Park decreased from 150 in 1850,
  to less than 50 today they predict that there
  will be none in 30 years.
• As the glaciers melt, less clean water is
  available for human use, and sources for crop
  irrigation are lost.
• Worldwide, more than 1.5 billion people currently
  depend upon glacial sources for water.
• Much of the American West is habitable only
  through water from glacial sources.
• 70 of the snow packs of the Western United
  States will be gone by the middle of the century.

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Rising Ocean Levels

• The ocean could rise as much as one meter in this
  century, due to melting in the polar ice caps.
• This may not sound like much, but the
  repercussions are huge.
• Millions of people in crowded costal areas like
  Bangladesh, Shanghai, even Florida and Manhattan
  will be forced to relocate as these areas become
  uninhabitable.
• 40-50 of costal wetlands could be wiped out,
  killing off plant and animal species and leaving
  inland areas more susceptible to storms like
  hurricanes and tsunamis.

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Life on a Warm Planet

• Global warming will have a serious effect on the
  worlds plant and animal life.
• Species biodiversity will suffer as hundreds of
  thousands, if not millions, of species become
  endangered or go extinct.
• Humans will be especially affected by global
  warming.

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Biodiversity

• Because global warming is altering the climate so
  rapidly, many species of plants and animals will
  have no time to adapt.
• These species risk endangerment and extinction.
• Many of these species already face hardship
  thanks to deforestation and other human
  activities.
• The first extinction attributed entirely to
  global warming was the golden toad of Costa Rica.
• Polar habitat animals, such as Arctic foxes,
  penguins, and polar bears, are literally seeing
  their homes melt away.
• Rising temperatures in the ocean are killing off
  essential organisms like algae, plankton, and
  coral.
• Animals higher up in the food chain will see a
  loss of food supply and soon face the extinction
  risk as well.
• Meanwhile, other species will thrive in the new
  climate and migrate around the world, throwing
  the planets biodiversity off balance.

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The Human Toll

• The species accelerating global warming stands to
  lose much due to climate change.
• Entire regions could become completely
  uninhabitable to us for reasons including
• Rising sea levels
• Desertification
• Intense heat
• Loss of usable water
• Loss of usable soil

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The Human Toll

• Clean freshwater will become a precious and
  increasingly rare commodity as our glaciers,
  lakes, rivers, and groundwater sources dry up.
• Crop and livestock species will become less
  diverse and more susceptible to disease and
  climate change.
• Diseases like malaria, already one of the worlds
  worst killers, will multiply around the world as
  temperate regions get warmer.

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Are we past the point of no return?
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Solutions

• Most experts believe there is still time to avoid
  drastic climate change.
• However, there is no magic bullet to solve the
  coming crisis and reverse the damage we have done
  to the environment.
• Instead, a series of changes must be implemented
  now. These necessary changes range from
  large-scale to small-scale.
• The focus of these changes is to dramatically
  reduce our greenhouse gas emissions.

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Solutions

• To stabilize the climate at at its present level,
  we must cut greenhouse gas emissions by 70.
• To actually reduce atmospheric greenhouse gases,
  we must cut emissions still further.
• Solutions fall into two general categories
• Reducing energy use
• Investing in alternative energy

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Large-Scale Solutions

• The Kyoto Protocol is the first international
  agreement to cut emissions of carbon dioxide and
  five other greenhouse gases.
• The signatories agree to cut their emissions to
  1990 levels.
• The United States and Australia are the only
  countries yet to sign Kyoto.
• The European Union plans to reduce emissions 20
  by 2020. They hope to do this through a number of
  initiatives
• Add 15,000 megawatts of wind power (enough to
  supply half the population of Europe)
• Increase ethanol production five-fold
• Increase biodiesel production three-fold
• Germany plans to cut its emissions 67 by 2050 by
  cutting energy use and using renewable energy.
• Iceland already heats 93 of its homes with
  renewable geothermal energy.
• Many nations are investigating cap and trade
  programs that limit greenhouse gas emissions.

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Small-Scale Solutions

• Fixing the climate is not just an international
  matter. Is is within reach of the average person.
  
• There are many things you can do to reduce your
  greenhouse gas emissions
• Drive less or get a fuel-efficient car
• Eat local foods as much as possible
• Use an efficient heating and cooling system in
  your home
• Use fluorescent light bulbs
• Buy renewable power from your electric utility or
  install renewable energy sources in your house
• This is far from a complete list of options.
  Learn more ways to reduce your greenhouse gas
  emissions at www.livegreenlivesmart.org

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America ranksnumber one as a producer of
greenhouse gases.

• Americans must participate in efforts to halt and
  reverse global warming.
• If a basic understanding of the causes and
  dangers of rapid climate change is paired with
  the knowledge of better choices, we can
  immediately begin the work of saving the planet
  for future generations.

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Thank you for your time and attention.

• This has been a
• Live Green, Live Smart presentation.

www.livegreenlivesmart.org