“Rare Snowfall Stuns Johannesburg” That is the title of a Weather Channel report dated 08/07/12.
Meanwhile, on 08/14/12, Weather Channel senior meteorologist Tom Moore reported that the state of Missouri could experience record low temperatures during the next few days as a cold front pushes southward through the central USA.
In case someone wishes to use the snow in Johannesburg, South Africa or the predicted low temperatures in the USA as “proof” of man-made global warming, I want to quote from the written testimony of climatologist John Christy:
My point is that extreme events are poor metrics to use for detecting climate change. Indeed, because of their rarity (by definition) using extreme events to bolster a claim about any type of climate change (warming or cooling) runs the risk of setting up the classic “non-falsifiable hypothesis.” For example, we were told by the IPCC that “milder winter temperatures will decrease heavy snowstorms” (TAR WG2, 126.96.36.199.2.4). After the winters of 2009-10 and 2010-11, we are told the opposite by advocates of the IPCC position, “Climate Change Makes Major Snowstorms More Likely” (http://www.ucsusa.org/news/press_release/climate-change-makes-snowstormsmore-likely-0506.html).
The non-falsifiable hypotheses can be stated this way, “whatever happens is consistent with my hypothesis.” In other words, there is no event that would “falsify” the hypothesis. As such, these assertions cannot be considered science or in any way informative since the hypothesis’ fundamental prediction is “anything may happen.” In the example above if winters become milder or they become snowier, the non-falsifiable hypothesis stands. This is not science.