He probably knows this is a safe bet! The trend of warming is "rapid" in geologic terms but still well within the variability of weather at any particular spot over a decade.

He wants to bet on weather prediction, not climate. Nobody's making weather predictions for specific spots a year ahead, let alone a decade, point by point. The world isn't simple enough for that to make sense.

He wants to throw away 99.9999 percent of the data, knowing the rate of change measured can't be shown with ten thermometers over ten years. He's certainly proving his skill in marketing and advertising by the proposal.

Given a _huge_ data set (far more than ten instruments) a ten year trend isn't reliably detectable. This isn't a guess, it's from work done in the data set that's already available.

http://www.cru.uea.ac.uk/cru/data/temperature/

You can do the math yourself.

And you can see it done for you.

http://scienceblogs.com/stoat/2007/05/the_significance_of_5_year_tre.php

At least look at the picture:
http://scienceblogs.com/stoat/upload/2007/05/5-year-trends.png

"... the series is definitely going up; that 15 year trends are pretty well all sig and all about the same; that about 1/2 the 10 year trends are sig; and that very few of the 5 year trends are sig."
So I'm afraid Dr. Armstrong's bet is right up there with Lord Whatsisname's debate ----- an invitation to play on their own terms when they know they can't lose, because they want the publicity.

However, just because it's difficult to scientifically prove a future outcome doesn't mean that the outcome is any less likely to occur. The problem with the entire global warming debate is that it's actually about risk management- not about whether one party is right and another party is wrong.

Rather, policy-making must take into account the likelihood of a given outcome- and this case it's neither 100% or 0%, but somewhere in between. Those with positions on both sides of the global warming debate continue to ignore this reality.

I've long suspected that the global warming alarmists are less interested in the environment than finding a threat that enables them to exercise ever-greater control over the way people live. It is the perfect vehicle for expanding the power of government(s) to be evermore intrusive and controlling of individuals.

As HL Mencken said, "The whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins, all of them imaginary."

Just so here.

The weakness of modeling and prediction was also discussed in the book "Chaos" by James Gleick. It specifically discussed weather models but the ideas can be applied to all sorts of computer models and the unreliability of those results.