It’s always nice to have a spirited discussion with someone who takes these issues seriously.

Which is what… maybe five or six of us?

Reason is in short supply, and middle ground is getting harder to find.

FAR too many people assign some evil motive one way or the other. We both agree that technological innovation will get us to a cleaner future, and that clean for “clean’s sake” is worthy, where it makes sense economically. Where we differ is on which direction will ultimately spur the innovations that make cleaner energy a reality – and recognition of a common goal removes a lot of unnecessary heat from debate.

Thanks for coming by — and feel free to peruse the other 99-percent of my content that is not focused on this issue!

- Coincidence
- Correlation
- Causality.

Of those, causality is the most difficult to prove, particularly when you look at the record from 12K-10K years ago. It is very clear according to that graph that the warming occurred prior to the increase in CO2 levels. If indeed there is a natural process whereby already-occurring warming leads to a rise in CO2, then the models that count on a high-positive feedback effect from higher CO2 concentrations have over-calculated the effects.

I agree that humanity has prospered under a relatively stable period of Earth’s recent climate history. I differ with you, though, on the idea that we ought to be spending vast resources trying to change a dynamic that is bigger than any of us — when we could allocate other resources to help people affected by the symptoms.

Spending trillions of dollars to slow down the rate of warming by only two weeks every hundred years is not that big an impact — and I would submit that the science is indeed not settled about what the climate would have been had CO2 never risen.

Now… if you want to make the case against carbon based on ocean acidification, I am listening.

But I will — to my dying breath — vehemently reject ANYONE who believes it is okay to lie about science “because it’s in our best interests.” There is no place in science for scare tactics, and there is no place in science for ends justifying means. If the threat is from acid oceans, then don’t cram a bunch of unproven doomsday scenarios down my throat and frighten schoolchildren for the sake of an agenda.

And those who are truly interested in science for its own sake ought to be going into schools, and telling the doomsday prophets to shut up. Particularly those who don’t care one whit about science, but are interested in puncturing growth and economic freedom to pursue their own economic agenda.

You will admit there are people hiding behind the patina of Environmentalism, who have no idea what they are talking about but enjoy the power the fear would give them. (Just as I will admit there are entrenched interests who refuse out of hand any conclusions that get in the way of business as usual, and don’t bother discriminating between the good science and the bad.)

Your graphs, from one greenland ice core, are consistent with other ice core, sediment core and pollen distributions. They all show a remarkably consistent range of temperatures over the last 10,000 years.

Our concern about “the tick” is not just that it is an increase. But, it is the rate that the increase is occurring coupled with a human caused spike in CO2 levels that is cause for alarm. http://www.brighton73.freeserve.co.uk/gw/paleo/20000yrfig.htm

Coastal flooding is just the most obvious result climate change. Other results include increases in tropical cyclone intensity, frequency of heatwaves, crop failure, forest fires, and drought. These are all effects of a 5 degree increase in temperature or less.

I am not debating fragility of the environment or climate. To take your example it would be worth it to shift some of our resources to diverting an impending asteroid collision not because of the overall effect on the environment, ecosystems adapt over thousands of years, but because human lives are at stake now.

Your perspective on this has everything to do with maintaining the status quo, and how it will affect the near term.

Long term, spending trillions of dollars trying to slow a change – where at best, we will have a negligible impact – is folly. When compared to the many other threats we face, making a few people move away from the present coasts is a pretty minor deal.

The fragility of the environment and the climate is in serious question. We’re made to believe that we’re sitting on a delicate balance on the point of a pin, and we’re just one bad nudge or lean away from tipping forever. Long term, I am far more worried about how we’ll cope with a 10-degree Celsius drop within a 250-year time span, which is the ticking time bomb of the next ice age. Or to die from a comet, knowing that had we not frittered trillions of dollars to “slow the warming” by 2 weeks per century instead of investing in research and global defense.

Earth climate has varied significantly over geological ages. The question of an “optimal temperature” makes no sense without a clear optimality criterion. Over geological time spans, ecosystems adapt to climate variations. But global climate variations during the development of human civilization (i.e., the past 12,000 years) have been remarkably small.

Human civilization is highly adapted to the current stable climate. Agricultural production depends on the proper combination of soil, climate, methods, and seeds. Most large cities are located on the coast, and any significant change in sea level would strongly affect them. Migration of humans and ecosystems is limited by political borders and exisiting land use. In short, the main problem is not the absolute temperature, but the massive and unprecedentedly fast change in climate, and the second order-effects to human societies.

http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch19s19-3-1.html