Equal Time for President Bush

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Equal Time for President Bush
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The IPCC 2007 report

• Global atmospheric concentrations of carbon
  dioxide, methane and nitrous oxide have increased
  markedly as a result of human activities since
  1750 and now far exceed pre-industrial values
  determined from ice cores spanning many thousands
  of years.
• The global increases in carbon dioxide
  concentration are due primarily to fossil fuel
  use and land-use change, while those of methane
  and nitrous oxide are primarily due to
  agriculture.

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• 11 of the past 12 years are the warmest since
  reliable records began around 1850

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• Global warming is "very likely" caused by man,
  meaning more than 90 percent certain. That's the
  strongest expression of certainty to date from
  the panel.
• If carbon dioxide concentrations in the
  atmosphere reach twice their pre-industrial
  levels, the report said, the global climate will
  probably warm by 3.5 to 8 degrees. But there
  would be more than a 1-in-10 chance of much
  greater warming, a situation many earth
  scientists say poses an unacceptable risk.

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• A snow-maker created snow on the slopes of
  Parsenn in Davos, Switzerland in February. Many
  attribute this winter's low snowfall to global
  warming.

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• But if the world does get greenhouse gas
  emissions under control _ something scientists
  say they hope can be done _ the best estimate is
  about 3 degrees Fahrenheit.

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• Sea levels are projected to rise 7 to 23 inches
  by the end of the century. Add another 4 to 8
  inches if recent, surprising melting of polar ice
  sheets continues.
• Sea level rise could get worse after that. By
  2100, if nothing is done to curb emissions, the
  melting of Greenland's ice sheet would be
  inevitable and the world's seas would eventually
  rise by more than 20 feet, Bindoff said.

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That amount of sea rise would take centuries,
said Andrew Weaver of the University of Victoria
in Canada, but 'if you're in Florida or
Louisiana, or much of western Europe or southeast
Asia or Bangladesh ... or Manhattan ... you don't
want that,' he said.
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• The debate over whether global warming is
  happening and that it is anthropogenic is over
  (fierce resistance from petroleum companies is
  now past) but now the debate is what does it
  cost to reduce carbon emissions to certain levels
  that will prevent the worst harm?)

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The Stern Report-2006

• The economic model used in the Stern Review finds
  that the damages from business as usual would be
  expected to reduce GDP by 5 based on market
  impacts alone, or 11 including a rough estimate
  for the value of health and environmental effects
  that do not have market prices (externalities,
  in the jargon of economics). If the sensitivity
  of climate to CO2 levels turns out to be higher
  than the baseline estimates, these losses could
  rise to 7 and more than 14, respectively.
• A disaggregated description of impacts by sector
  and region is generally in agreement with these
  numbers, according to the Review. Stern
  speculates that an adjustment for equity
  weighting, reflecting the fact that the impacts
  will fall most heavily on poor countries, could
  lead to losses valued at 20 of global GDP.
• These figures are substantially greater than the
  comparable estimates from most economists

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• These damages can be largely avoided, at much
  lower cost, through emissions reduction (or
  mitigation, in the jargon of climate change).
  Stabilization at 500550 parts per million (ppm)
  of CO2-equivalent7 in the atmosphere would avoid
  most, though not all, of the business as usual
  damages.
• Both direct estimates of mitigation costs and a
  review of results from many different models
  suggest that stabilization at this level would
  cost about 1 of GDP. Stabilization below 450
  ppm, according to Stern, is no longer feasible

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• First, what is the maximum atmospheric
  concentration of CO2 at which unacceptable
  climate outcomes can be ruled out with a high
  degree of confidence?
• Second, what is the least-cost strategy for
  stabilizing at that concentration?
• The first question is the essence of a
  precautionary approach to policy, in a context of
  complex and uncertain scientific information. It
  involves several difficult, but not impossible
  judgments about the (probabilistic) link between
  CO2 levels and climate outcomes about which
  climate outcomes are unacceptable and about how
  high a degree of confidence is required that we
  can avoid those outcomes.

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What To Do?

• Adaptation-Favorite argument of neoclassical
  economists.
• They believe that large uncertainties in climate
  projections make it unwise to spend large sums
  trying to avert outcomes that may never
  materialize.
• They believe that human systems can adapt to
  climate change much faster than they occur.
• They maintain that while doubling of CO2 will
  take place over the next century, financial
  markets adapt in minutes, labor markets in
  several years, and the planning horizon for
  significant economic and technological change is
  at most two or three decades.
• But what are the risks of large, abrupt, and
  unwelcome shifts in climate?

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Mitigation

• curtailing the greenhouse gas buildup to
  prevent, minimize, or at least slow global
  warming (harper, p. 97)
• White surfaces and vegetation.
• Residential water heating.
• Residential space heating
• Residential and commercial lighting.
• Industrial energy management
• Fuel efficiency

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Transportation Energy Management

• Vehicle efficiency
• Alternative fuels (ethanol from biomass,
  solar-hydrogen)
• Transportation demand management
• Electricity and fuel supply

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Carbon Tax?

• tax on energy sources which emit carbon dioxide
  into the atmosphere. It is an example of a
  pollution tax, which some economists favor
  because they tax a "bad" rather than a "good"
  (such as income). Because a carbon tax addresses
  a negative externality

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Equity issue that Harper raises (p. 101)

• the regressivity of a carbon tax could be
  minimized or eliminated by allocating the tax
  revenues to benefit the less affluent.
• Wealthier households use more energy, on average
  they drive and fly more, have bigger (and
  sometimes multiple) houses, and buy more products
  that require energy to manufacture and use. Most
  carbon tax revenues will therefore come from
  families of above-average means, as well as
  corporations and government.
• This creates a basis for progressive
  tax-shifting transferring a portion of the tax
  burden from regressive taxes such as the payroll
  tax (at the federal level) and the sales tax (at
  the state level) onto pollution and
  pollution-generating activities.
• Another progressive approach in the United States
  is to rebate the carbon tax revenues equally to
  all U.S. residents a national version of the
  Alaska Permanent Fund, which once a year sends
  identical checks to all state residents from the
  states North Slope oil royalties. Because income
  and energy consumption are strongly correlated,
  most poorer households would get more back in
  rebates or tax savings than they would pay in the
  carbon tax.