Out of curiosity I created a graph of annual average temperature anomalies based on HadCRUT3 temperature data but omitting 1943-1971 .
I don’t for a moment believe that the HadCRUT3 data is accurate and reliable, however, I found the graph interesting.
I remind you that IPCC attributed the first half of the rising period to natural causes and the second half to human activity.
I think it looks more like consistent warming out of the Little Ice Age and the omitted period is a time when La Nina conditions dominated. Another hypothesis is that the rise in temperature is due to increasing night-time cloud cover due to industrialisation.
Cheers, John McLean
Click on graph image for larger view.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
A neat way of showing that the rate of temperature increase before AGW supposedly set in is the equivalent of the rate of increase after; so AGW took over at exactly the same rate as the natural factors did at exactly the same time as the natural factors ceased; damned clever!
Monckton has been belting on about this and getting abused for his troubles, see page 8 of this:
http://scienceandpublicpolicy.org/images/stories/papers/reprint/markey_and_barton_letter.pdf
Monckton calls it the end point fallacy and it can be shown many ways:
http://jonova.s3.amazonaws.com/graphs/hadley/Hadley-global-temps-1850-2010-web.jpg
Figures 15 and 16 here:
http://www.rocketscientistsjournal.com/2010/03/sgw.html
John, John, John, you’re doing it wrong! You’re supposed to subract each year’s average temperature from the next year’s average and plot the differences.
By the way, I look forward to you, Jennifer or cohenite publishing a plot with equal time intervals on the horizontal axis, instead of packing the 53 years from 1930 to 1983 into the same space as you used for 20 year intervals. The way you have plotted the graph might make people think you are trying to disguise something that happened in the years from 1970 to 1990.
The cuckoos that hysterically shreik as winter turns to summer forever tell us that it is not so much the warming as the “unprecedented rate” that is exceptional.
This graph shows just how “unprecedented” that warming rate really is.
But when you further compare the cooling of each successive warm period for the past few thousand years……
Hi John, I read somewhere recently that you were doing a PhD in climate change at James Cook University. Who are you studying under and what are you researching? Thomas