I’m sure you agree–the Mann/Jones GRL paper was truly pathetic and should never have been published. I don’t want to be associated with that 2000 year “reconstruction”.
And here it is: “Global surface temperatures over the past two millennia” aka “Mann, M. E., and P. D. Jones, Global surface temperatures over the past two millennia, Geophys. Res. Lett., 30(15), 1820, doi:10.1029/2003GL017814, 2003.”
We present reconstructions of Northern and Southern Hemisphere mean surface temperature over the past two millennia based on high-resolution ‘proxy’ temperature data which retain millennial-scale variability. These reconstructions indicate that late 20th century warmth is unprecedented for at least roughly the past two millennia for the Northern Hemisphere. Conclusions for the Southern Hemisphere and global mean temperature are limited by the sparseness of available proxy data in the Southern Hemisphere at present.
Reconstructions of hemispheric mean temperatures over roughly the past two millennia employing proxy surface temperature data networks with sufficient spatial and seasonal sampling, temporal resolution, and retention of millennial-scale variance, support previous conclusions with regard to the anomalous nature of late 20th century temperature at least about two millennia back in time for the Northern Hemisphere. To the extent that a ‘Medieval’ interval of moderately warmer conditions can be defined from about AD 800– 1400, any hemispheric warmth during that interval is dwarfed in magnitude by late 20th century warmth. The sparseness of the available proxy data in the Southern Hemisphere lead to less definitive conclusions for the SH or global mean temperature at present.