Global-warming pusher Michael Mann: Someone's lying

Michael Mann is a PhD at Penn State who is one of the most aggressive U.S. pushers of the theory of "catastrophic anthropogenic global warming" (CAGW). 

Summary of the CAGW theory:
    a) the planet is warming at an alarming, dangerously-higher-than-normal rate;
    b) if true, this warming is primarily or mainly caused by carbon dioxide;
    c) the source of this supposedly unprecedented, dangerous CO2 is human activity, mainly burning oil, gas and coal;

Mann's major contribution was a study that purported to show that after being essentially flat for centuries, in the last half of the 1900's the planet's average temp had suddenly, alarmingly swung sharply upward, like the blade of a hockey stick laying flat.

His study did this by using the width of tree rings, of trees less than 150 years old, as an indicator of global temperature, and splicing this data onto older proxy data from other sources.  And there are several problems with this:  First, the width of tree rings is hugely affected by rainfall as well as temperature, and it's impossible to determine the relative contribution of each factor.

Second, his team had samples from something like 238 trees.  But they only used something like 12 for their paper.  Probably doesn't strike you as a concern, but since measuring and including all the samples wouldn't have involved a big effort or cost, why just use 12?  Unless the samples were selected completely randomly (something not mentioned in the paper) one reasonably suspects he may have used just the trees that supported his desired result.  This is called "cherrypicking your data" and is evidence of either incompetence or fraud.

Third, he didn't convincingly match his tree ring data to his other proxy data.  Essentially he simply joined the early end of his tree ring data to the end of different proxy data collected by others.  Sketchy stuff.

Oh, did we mention that Mann has the full backing of Penn State?  And that when someone copied and released 50 megabytes of emails between Mann and his co-conspirators at the UK's University of East Anglia "Climate Research Unit," showing them discussing ways to use personal friendships with journal editors to prevent papers debunking CAGW from being published--literally, in that language--both universities clammed up.
 
From: Phil Jones
To: “Michael E. Mann”
Subject: HIGHLY CONFIDENTIAL
Date: Thu Jul 8 16:30:16 2004
I can’t see either of these papers being in the next IPCC report. Kevin and I will keep them out somehow – even if we have to redefine what the peer-review literature is!
Cheers
Phil

450 Peer-Reviewed Papers Supporting Skepticism of “Man-Made” Global Warming That they Tried to Keep out of the IPCC Report.

No one at either university was disciplined in any way for engaging in what seems to be obvious fraud, let alone conspiring to prevent contradictory papers from being published.

Oh, but there's more!  The hacked emails reveal Mann and his main co-conspirator Phil Jones discussing how to "hide the decline" and how to make the well-known "medieval warm period"--the one that enabled the Vikings to grow grapes in Greenland for a century or so--vanish, so as to make it appear that earth's climate had never been warmer in the past, and was usually very constant.  Neither of these things was true.



Oh, if you want a quick primer on Climategate, don't bother reading Wiki.  I've personally read about 3000 of the hacked emails, and the Wiki piece is a total whitewash--its only resemblance to the truth is the statement that everyone was exonerated by their respective employers.

Of course, cupcake.

Source.