The recent paper by McIntyre and McKitrick (Energy and Environment, 14, 751-771, 2003) claims to be an "audit" of the analysis of Mann, Bradley and Hughes (Nature, 392, 779-787, 1998) or "MBH98". An audit involves a careful examination, using the same data and following the exact procedures used in the report or study being audited. McIntyre and McKitrick ("MM") have done no such thing, having used neither the data nor the procedures of MBH98. Thus, it is entirely understandable that they do not obtain the same result. Their effort has no bearing on the work of MBH98, and is no way a "correction" of that study as they claim. On the contrary, their analysis appears seriously flawed and amounts to a gross misrepresentation of the work of MBH98. The standard protocol for scientific journals receiving critical comments on a published paper is to provide the authors being criticized with an opportunity to review the criticism prior to publication, and offer them the chance to respond. Mann and colleagues were given no such opportunity.
It seems clear that MM have made critical errors in their analysis that have the effect of grossly distorting the reconstruction of MBH98. Key indicators of the original MBH98 network appear to have been omitted for the early period 1400-1600, with major consequences for the character of the MM reconstruction of Northern Hemisphere temperatures over that interval.