Many studies subsequent to the original Mann et al study have confirmed the reality that the recent warming is likely unprecedented in the last thousand years.
Its message is starkly clear, so climate deniers have desperately attempted to invalidate it.
In 2006 the US Congress held a hearing on the validity of Mann's work.
Here is his testimony to the committee:
Recently Mann has produced a book on the science and the personal attacks that have been launched at him. the book is: The Hockey Stick and the Climate Wars.
In the video below, Peter Sinclair, interviews Michael Mann.
I have been reading a book which is effectively a history of the last 14,000 years called Why the West Rules - For Now. The author Ian Morris has constructed an index of social development.
While reading the book I came across another hockey stick - Morris's index:
(Click on the images for a larger version.)
For more details on the index that Morris developed click on this link.