Reference
Shi, X.-H., Qin, N.-S., Zhu, H.-F., Shao, X.-M., Wang, Q.-C. and Zhu, X.-D. 2010. May-June mean maximum temperature change during 1360-2005 as reconstructed by tree rings of Sabina Tibetica in Zaduo, Qinghai Province. Chinese Science Bulletin 55: 3023-3029.
Description
Working in an old-growth forest in Nangcai, Zaduo County, at a site (32°39'36"N, 95°43'14"E) undisturbed by human activities, Shi et al. extracted 67 cores from 29 healthy trees with long ages, after which they measured the widths of their annual rings and created a ring-width history covering the period AD 1360-2005, based on what they considered to be the best 46 cores from 23 trees. Then, for the period AD 1961-2005, they derived a relationship between annual tree-ring width and directly-measured May-June mean maximum air temperature, which they used to reconstruct a similar temperature history for the entire 645-year period. Based on an eleven-year moving-average of these results, they finally identified a 17-year warm period (AD 1438-1455), which occurred in the latter stages of the global MWP, which as best we can determine from the graphs of their results was about 1.2°C warmer than the last decade of their temperature history (AD 1995-2005).