Overshoot - the road we couldn't take, and the road we did.

[GliderGuider]

9. A few further comments, for those who want to save civilization.

• Politics has nothing to offer this situation. The biophysical driver of fossil fuel energy transcends all political boundaries and philosophies.
  
• Fossil fuels have supplied 89% of the total primary energy used throughout the world over the last 55 years, and supply 87% of the energy used today, according to BP Statistical Review 2011).
  
• Agriculture started the ball rolling about 8,000 years ago, and got our population to 1.8 billion in 1900 without fossil fuels. But the logistical curve didn't take off until the serious use of fossil fuels began in about 1900. To a first approximation, everything we've done since 1900, including agriculture, has been the result of our use of fossil fuels. That's the point of the green line in the original graph.
  
• We are too close to the inflection point (~20 years or less), and have built too much fossil-dependent infrastructure, for renewables to do more that act as a buffer in some places against the most egregious effects of the decline.
  
• The correlation of primary energy and world population is self-evident. The following graph uses Gail Tverberg's energy graph from the OP as the reference point for energy.