The Global Warming Crisis

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The Global Warming Crisis

• A Brief Summary of the EvidenceAssembled by M.
  Frank2/3/07

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• Atmospheric CO2concentrations have increased
  36 (375 ppm/275 ppm) since pre-industrial
  times.
• This increase is accurately accounted for by
  fossil-fuel emissions (and absorption in the
  oceans).
• Multiple paleoclimaticrecords confirm this
  increase is well outside the normal range of
  variability for CO2 levels (180-300 ppm) that has
  held over thelast 650,000 years.
• The recent sharp rate of increase is also well
  outside the natural ranges.
• CO2 levels around 1,000 ppm (which wewill reach
  in lt200 yrs.if nothing is done) have been
  implicatedin past mass extinctions that killed
  90 of all life on Earth (Scientific American,
  October 2006.)

Source IPCC 4th Assessment Report, Summary for
Policymakers
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Graph from IPCC 3rd Assessment

• Global temperatures have also followed a very
  similar trend, with both the absolute value and
  sustained rate of increase well outside the
  normal range of variation for at least the past
  1,000 years.
• The last time the polar regions were
  significantly warmer than present for an extended
  period (about 125,000 years ago), reductions in
  polar ice volume led to 4 to 6 metres of sea
  level rise. (IPCC FAR)

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• Numerous supercomputer climate models have
  confirmed that the observed temperature increases
  can be accurately accounted for if anthropogenic
  greenhouse gases are taken into account, while
  the observed increases absolutely would not have
  occurred given only the natural causes of
  variation (including variations in solar
  irradiance together with volcanic emissions)
• Source of graph Presentation Climate Simulation
  for Climate Change Studies by D. Bader (Lawrence
  Livermore Natl Lab), workshop on Frontiers of
  Extreme Computing, Oct. 05.

Simulations with man-made effects predict the
observed warming, right on target!
Simulations without human impact are way off the
mark!
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Conclusion

• The scientific evidence is unequivocalWE ARE
  CAUSING GLOBAL WARMING.
• The biggest question remaining is
• Are we going to have the courage to stand up and
  do something about it, try to solve the
  problem?
• Or, are we going to condemn our children and
  grandchildren to deal with the consequences?
• Coastal flooding, increased storm intensity,
  acidification and deoxygenation of the oceans due
  to CO2 absorption (already starting to occur!),
  the eventual death of most marine life (many
  coral reef ecosystems worldwide are already
  dying!), and possible eventual poisoning of the
  atmosphere from H2S gas that will be emitted in
  huge volumes by the anaerobic bacteria that will
  take over the dead and rotting seas
• Which future will it be?