Wednesday, September 26, 2012

Foxy photo

I've been wanting to photograph a fox for a long time. Last Sunday I got my chance when two foxes appeared on our lawn. They seem to have taken a liking to our bullaces (wild plums) or perhaps, as the all too copious evidence suggests, taken to using them as a laxative.

It was a very gloomy and wet afternoon so the image isn't as bright and sharp as I would like - long lens (300mm on a DSLR), slow shutter speed (1/80 sec), photo taken through the glass of the window. One day I hope to get one with its whiskers glistening in the sun.

Political Prejudice

An interesting Analysis programme recently on BBC Radio4, available on iPlayer, entitled Political Prejudice - "Why do right-wingers tend to be sceptical about global warming, and why do left-wingers often doubt the value of IQ tests? Michael Blastland investigates our cognitive biases."

Highly relevant to my last three posts. Thanks to my friend who drew my attention to this.

Wednesday, September 19, 2012

Yet more on Lord Lawson's speech (wonkish)

Oh dear, I can't let go of this Lawson thing. I find when I start exploring numbers like the HADCRUT3 dataset, it's difficult to stop.

In yesterday's post I confirmed what Lord Lawson said in his recent speech, that the temperature record for the past fifteen years shows no warming trend. I then suggested that this was not a very meaningful measure because movement within a period of ten or fifteen years tends to be dominated by noise in the system.

The trend I calculated was a global warming rate of 0.004 degC per year, or 0.4 degC over a century which I thought low enough to be deemed insignificant. Curiosity then led me to try the same - a calculation of the 15-year warming trend - for the periods ending in each of the previous 30 years. This is what I got:-
Past 15-year warming trends for periods ending between 1982 and 2011 Source: HADCRUT3 dataset

Tuesday, September 18, 2012

Has global warming ground to a halt?

Last week I did a long posting about a recent speech by Lord (Nigel) Lawson. There was one bit I didn't comment on. He said:

"The fact that there has been no recorded global warming trend for the past 15 years or so, during which CO2 emissions have grown very rapidly indeed, thanks in large part to remarkable economic growth in China, suggests that the climate sensitivity of carbon is in fact less than is incorporated in the models on which, for example, the IPCC relies."

The opening phrase of that quote surprised me. I was under the impression that global warming had continued, albeit with a brief downward trend in the mid noughties. Figure 1 is a graph of the raw figures, from the HADCRUT3 dataset, for the past 15 years with the trend line shown in orange. As you can see, the trend line has only a very shallow slope, probably insignificantly different from zero.

Figure 1 - Source: HADCRUT3 dataset

Thursday, September 13, 2012

Why I disagree with Lord Lawson

In August 2012, Nigel Lawson presented a paper to the Erice conference entitled Rational climate economics.

Early in the paper he goes in for some political knockabout at the expense of climate scientists:-

"There is now a new religion – the AGW [anthropogenic global warming] religion, of which scientists are the new priesthood, preaching their dogma with precisely the same claim to authority as the mediaeval catholic church."

He goes on: "The truth is, as the best scientists recognise, that the greenhouse effect is a highly complex phenomenon, and the scale of the climate sensitivity of carbon is hugely uncertain."

In spite of what he says about the uncertainties, towards the end of the paper he displays his confidence that we need take no action to reduce the risks of seriously harmful climate change. He says we can rely exclusively on adaptation to global warming as the most cost-effective response. There appears some inconsistency here between the alleged hugeness of the uncertainty and his confidence that global warming will be mild enough for us to cope with through adaptation.