In 1990 the IPCC AR1 paper showed the lamb graph which clearly shows a Medieval Warm Period (MWP) & a little Ice Age (LIA).
In 2001 they took out the lamb graph and replaced it with Mann's famous hockey stick.
Mann was challenged many times by sceptic climate scientists to provide his working out of how he came about the hockey stick, some went on to work it out for themselves and then published the results which showed Manns hockey stick was fraudulent.
Another scientists Tim Ball called him (Mann) out on this, Mann got furious and sued Tim Ball.
They went to court after 8 years because Mann kept delaying it.
In court Mann would not show his working out and how he came to the conclusion of the hockey stick, a classic case of the science is settled sit down and shut up.
Well the court got fed up with him and awarded Tim Ball the win, Mann had to pay costs.
Why wouldn't Mann show his working out, if it is true (the hockey stick) and he can prove it why didn't he show the working out.
But wait there's more.
In the IPCC AR5 paper Manns Hockey stick got thrown under a bus and the IPCC have now returned to something like the lamb graph that has a bump and a dip that represent the MWP and LIA.
Now I ask you what sort of peer review have the IPCC got going over there, they publish rubbish until proven false, where are their own checks...???
I bet no one at the IPCC checked the hockey stick there was no peer review until Tim Ball called it out along with many other climate scientist that are sceptical about the AGW religion, oops I mean science......
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And we are making plans to spend billions of tax payers monies on the stock market buying carbon derivatives because the IPCC says so.
F@rk me is it really that easy to make billions of dollars from billions of suckers.