OK. But how many years of cooling will it take before we begin to question AGW?
Sufficient to indicate an actual long term trend, rather than a short term anomaly.
A single year does not the trend make.
Given that most temperature records appear to show short term cooling trends of 2-5 years (i'm eyeballing it here mind), I would
expect that it would be far enough in excess of this. How do you define far enough in excess? The easiest way that I can think of would be to analyze all of the short term cooling trends on record (remember, there have been other periods of 'cooling'), compute a 99% confidence interval and go from there (something I could do, but lack the motivation at this time).
This blog post
warmest by fair margin made in August of this year makes for some interesting reading.
Regarding the claim 'the expected warming has not occured', the following two graphs, I thought were rather informative from here
Has Global Warming Ended?
NASA GISS data for 1975-2000, with an extrapolation to 2009.
NASA GISS data for 1975-2009, including the above extrapolation.
But, as you can see by reading that blog, this isn't just limited to the GISS data set.
One of the things I find interesting is that similar dips occured in '70s, '80s, and '90s as part of - and here's the irony natural
short term variation.
So, as the link says - demonstrate again where the inexplicable cooling is?
Also worth a read
Riddle me this
The author of the above blog suggests in
How Long that 15 years is the absolute minimum required to establish a trend, and
embarrassing questions poses some interesting points.
Also, this kind of argument has been used by the global warming crowd since the very begining. Remember Dr Hanson's testimony before congress in 1988? He purposely picked what was forcast to be one of the hottest days of the year and opened all the windows before the meeting to overwhelm the air conditioning. Thus creating the effect of everyone mopping the sweat from their brows to demonstrate the urgency of the global warming problem.
I don't generally feel compelled to respond to this sort of tactic, it comes across as dishonest and, to be frank, desperate, you're tring to make this incident seem dishonest, and then tar everybody else that would argue the same point with the same brush.
However, in this instance I will respond, but allo wme to make it explicitly clear, I am neither condoning nor condeming Hanson's methodology. But tell me something. Have you ever tried to convince a
politician that something they're not interested in, and have no background knowledge of is fundamentally and critically important?
I have. It's not easy, especially when rectifying the issue is going to involve spending substantial sums of money.
