Notes:  Inspired by the late Dr. Stephen Schneider, Professor and climate scientist at Stanford University, from a CD recorded from his address at the Climate One at the Commonnwealth Club in San Francisco on November 3, 2009.  http://www.climate-one.org/

Dr. Schneider explained the risks of not taking action vs. taking aggressive and effective action to resolve climate change.  He believed that taking the best course of action will not happen until we understand the risks.  He defined understanding the risks as: 'What can happen and what are the odds.'

He explained it with this analogy:

Suppose you noticed a spot on your lung from a chest x-ray you got for a different reason than looking for cancer.  It could be a healed lesion or the beginning of cancer.  You ask the doctor if you need surgery (a biopsy).  He responds surgery has risks, it is expensive, painful, and the tumor may be hard to reach.  In other words, there is a price to be paid for a false positive.  If you believe it is cancer and you choose surgery, you will pay a price.

What could go wrong if you wait and delay surgery?  The doctor responds, 'If you wait and it grows, we better take it out.'

Then you ask, 'What is the chance that if I wait and it grows, it becomes metastatic and then it will be too late and I will be dead?'  Whereas, I take it out now, in a precautionary mode, pay the surgery price that I might not need, and I lower the likelihood of being dead?' 

What is the right answer to this?  It depends upon your value judgment.  This is the same with the risk of climate change.  If we wait to take action, according to Dr. Schneider, we increase the likelihood of nasty consequences.  Just like that spot on your lung on a chest x-ray, are you willing to take that risk?