Clyde Burnett, Gilpin County. Our past benign climate was the result of our planet’s energy balance. Our heat radiation from the sun was just balanced by our heat energy loss to space. Our scientists of yesteryear had given this careful study and were happy to find that the details of this process made conditions on Earth unique for the evolution of our plants and animals and establishment of human civilizations.

It doesn’t work for any of our other planets; the surface temperature of Mars is cold and Venus is hot. And finally, about 50 years ago, Roger Revelle of La Jolla made the observation that our business as usual in generating energy without regard for pollution made for a geophysical experiment involving energy balance that would bear watching.

In response, measurements of atmospheric carbon dioxide were initiated by Keeling at Mauna Loa. Initial measured concentrations were about 315 ppm (parts per million of background molecules). This record was extended by proxy to earlier years indicating concentrations of about 280 ppm in 1800, near the beginning of the Industrial Revolution. Carbon dioxide is being documented at Mauna Loa and other locations with current average concentrations at 400 ppm. That is a relative increase of 43%, largely due to burning fossil fuels for electricity and transport.

Question:  What happens to the trapped heat of the greenhouse effect?

Answer:  About 90% goes to warm the oceans on 70% of the planet. The average global temperatures of the sea surface have increased 0.4oC since 1950. And some of the heat is mixed into deeper layers. Also, almost all glaciers worldwide have lost over 30% of their ice by melting, and the Arctic sea ice surface has decreased 40% in late summer.

This melting process actually occurs without temperature change; the latent heat that goes into melting is a large fraction of the amount that would be required to heat water from freezing to boiling.  Finally, we observe an additional average temperature increase of about 0.85oC (1.53oF) for the entire planet since the Industrial Revolution. These temperature changes drive additional climate changes with serious environmental consequences.

Question:  We hear that the experts say that a climate change cause is uncertain for various weather extremes like a flood, or drought, or windstorm happening in any certain location. Why don’t we just wait and see if bad things happen?

Answer: Let us do some risk assessment. Consider a simple familiar situation. We have a very valuable favorite home in our mountain foothills. So, do you slave on weekends to make a wildfire defensible zone and dig into your savings for comprehensive homeowner fire insurance?  You betcha!! The risk of a terrible personal disaster is too great. In fact your bank will also insist that your mortgage is guaranteed by that insurance.

How bad could the climate change be? The costs of disaster adaptation could escalate during your retirement. A comment from the IPCC 2014 report: “The cost of inaction will be horrendously higher than the cost of action.” It could make life very difficult and unpleasant for your children and grandchildren. It might eventually make it impossible for the human race to exist.

Perhaps we should engage what the climate experts call the precautionary principle. Let’s begin a reasonable control of CO2 emissions.