Denialism seems to be on the up

I was taken aback recently when an acquaintance of mine unexpectedly revealed him/herself (to make him/her as anonymous as possible) to be a global warming denialist. By "denialist" I mean someone who puts forward the view that the threat of global warming is not on such as scale that it requires serious action to mitigate it. So I include "lukewarmists", like Peter Lilley.

This struck me as a rather close-to-home indication of the way denialism in the UK seems to be on the up. As Fiona Harvey reported in The Guardian yesterday:-

"Some Tory MPs have taken to booing and jeering every time the Climate Change Act is mentioned in the Commons. A growing section of the party would like the Committee on Climate Change to be scrapped and the act repealed."

Now it's fair enough for people to have different opinions but most of us are not equipped to make a serious appraisal of the scientific evidence. So why should we come to a view one way or the other?

We shouldn't. Instead we should first regard catastrophic climate change as one of several possible scenarios. We should then assess whether catastrophe can be deemed, beyond reasonable doubt, to be so highly unlikely that we can ignore it.

I feel unable to rule out catastrophic climate change as a serious possibility. In fact, the probability of catastrophe, with 4 deg C or more of global warming by the end of this century, appears to me to be growing - both as evidence of present warming unfolds and as it becomes increasingly apparent that we are far from any peaking of man-made greenhouse gas emissions.

As I have said in a previous post, we may not simply be talking about bringing civilisation to an end a few decades hence. We may be setting ourselves on course for a runaway greenhouse effect that kills off all life on Earth long before the increasing heat from an aging sun would in any case render our planet lifeless - see Chapter 10 of James Hansen's Storms of my grandchildren.

Lots of scientists may say that Hansen is wrong. I would not presume to take sides in any argument between bona fide climate scientists (and they don't come much more bona fide than Hansen, who heads NASA's Goddard Institute.) Hansen's Venus Syndrome, as he calls his runaway greenhouse scenario, is there on the table, along with other scenarios that can reasonably be termed "catastrophic".

"Lukewarmists" like Peter Lilley may be proved right and future generations may find that the fears of people such as myself are unfounded. That doesn't stop me leveling this accusation against some of the denialists I have come across - that by turning a blind eye to the possibility that they may be wrong and that James Hansen may be right, they are showing a reckless disregard for the welfare of future generations.

I remember it was once common for young men to claim that they drove better when they were drunk. I tend to regard climate denialists in a similar light.