by Greg Krehbiel on 9 September 2013
There’s a proverb that goes “the first to plead his case seems just, until another comes and examines him.”
You may have seen that arctic ice increased this year, despite some projections that the arctic would be ice free.
Part of the problem here is the “report the craziest story you can find” ethic at newspapers.
“Polar bears will be dying next year for lack of ice” sells more ads than a sober story on what may be happening in the arctic.
Last year was a low year for arctic sea ice. This year there’s a lot more ice. “Look! Global cooling!”
No, it doesn’t work that way. The part in this article about regression toward the mean helps clear it up a little.
There’s a principle in statistics known as “regression toward the mean,” which is the phenomenon that if an extreme value of a variable is observed, the next measurement will generally be less extreme. In other words, we should not often expect to observe records in consecutive years. 2012 shattered the previous record low sea ice extent; hence ‘regression towards the mean’ told us that 2013 would likely have a higher minimum extent.
That article doesn’t tell the whole story either, but at least it puts it in some perspective.
I am still very skeptical about AGW. There is reason to believe that CO2 is a lagging indicator of changes in climate, not a cause. There are also reasons to believe that CO2 is a minor factor in climate. IMO there are a lot of good reasons to doubt the alarmist story, most particularly because they don’t seem to want to deal honestly with longer time periods.
The absolute biggest reason I doubt the AGW case is the shrill, nutty, dishonest rhetoric the advocates employ.
Still … you have to be honest about these things. This year’s increase in arctic ice no more disproves AGW than last year’s dearth of ice proves it. In another ten years we might have a decent chance of knowing if the AGW theory is correct — but only if scientists allow an honest dialog. In the current environment, there is very little hope of getting an honest answer.
-- 2013-09-09 » Greg Krehbiel