This week: Global warming stopped 15 years ago.
The idea:
Sure, if you look at temperature records, the world was warming from around 1980 to 1997. What they don't tell you though, is that it stopped warming then, and it's been about the same ever since. No really, we've got graphs and everything. The Earth has in fact slightly cooled since then. No need to worry, global warming is happening much slower than the Alarmists are saying. It's just a con to raise taxes.
I'm paraphrasing here, but I think those are the major points. Since I've been picking mostly on the Telegraph recently, here's the Daily Mail's version, just to mix it up a bit.
Why it's Bollocks:
The first point to make is that the only reason the "warming plateau" started 15 years ago is because 1998 is the third warmest year on record, behind 2005 and 2010. If you want to make a temperature series that shows a downward trend, it always makes sense to pick out a warm year, so that it's almost inevitable the next few years will be colder. That's manipulating data for a political agenda 101. This is an easy trick to pull so, in the name of science, here's a non-climate dataset to prove it.
I've put together the average attendances for each game from the English Premier League season between it's start in 1992 and 2012, taken from worldfootballnet. I could have chosen any dataset really, but I like football, and this one works quite well. Here's the figure we get out of it:
I've added a trend line in black, which just shows the average change over the whole time period. It's looking like happy times for football clubs, I'd hope you agree. The FA can crack out the champagne buffet, if they ever bothered to tidy the last one away. Hang on though..what if I just look at the period 2007-2012.
Oh dear, oh dear Barry. It's an economic crisis, and nobody can afford to go to the match anymore. The economy is sunk, the premier league is buggered and Gary Lineker will have to slink back off to his mountainous pile of crisps, which he sleeps atop like a dragon guarding his treasure hoard. Probably.*
The thing is though, this is the same data, so how come we got two totally different results? Well, because in the first case I used all the data I had, and in the second case I specifically chose when to start and finish to make it look like real world economics were having any effect whatsoever on the juggernaut that is the premier league.
This is exactly what's going on in the Daily Mail article, and lots of others like it. The truth is, although there hasn't been any drastic warming in the last 10 years, it's still true that the warmest 10 years on record are all between 1998-2012. As Phil Jones, head of the Climate Research Unit, discussed in this BBC Q+A, you can pick certain years and come up with certain trends, but they aren't statistically significant unless you look at the long term. Equally, if this year happens to be particularly warm, we won't suddenly be in a new warming trend; you just need to use as much data as you can to get a real picture of what is going on, because the bigger the dataset the more likely your trends are significant.
It's never a particularly good idea to trust sources that run these kind of articles, where somehow they think that the Met Office in the UK has just missed a trick that the clever journalist has spotted. Scientists aren't reporting a cooling trend because they understand the data, and they understand it isn't there. Not because it's a conspiracy.
*If you're American, and none of these jokes make any sense, then I apologize. I'm feeling a little spiteful after watching 4 days of basketball, in which I literally never have any idea what any commentator is on about ever.
