Slide 9 in this series.
The uptick in the recent period was both the result of errors made and the adding on of a current temp trend. It was just tacked on for good measure. This was used extensively in a IPCC AR report and as a center piece of the Inconvenient Truth, the movie by Al Gore.
The Hockeystick was only possible with 3 errors make intentionally. When confronted with the proof Michael Mann and several previously respected technical journals defended his methods and faught the disclosure. This is the most blatant confiscation of science for political reasons that perhaps has occurred in modern times.
Putting in random noise into this broken statistical method and a Hockeystick results. The coverup and the malicious intent was blatant anti-science.
NEXT: The IPCC on science and their methods.
The breakdown of the IPCC, its motives and methods are found in these pages.