The Global Warming Crisis

A Brief Summary of the EvidenceAssembled by M. Frank

2/3/07

• Atmospheric CO2

concentrations 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 <200 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

• 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)

Graph from IPCC 3rd Assessment

• 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 Nat’l Lab), workshop on Frontiers of Extreme Computing, Oct. ’05.

Simulations without human impact are way off the mark!

Simulations with man-made effects predict the observed warming, right on target!

Conclusion• The scientific evidence is unequivocal:

WE 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?