Figures 1-6 below show the normalised tree ring growth from the northern hemisphere and five individual countries. The aim was to use data from a range of longitudes. The countries and the number of sites can be viewed by clicking the three bar icon below to reveal a printable list.
Country Lead Researcher Site
Canada Parish Mt Cain
Canada Szeicz Spruce
Norway Kirchheffer Foffjorddalen
Norway Kirchheffer Stonglandseidet
Norway Kirchheffer Vikran
Russia Gervais Kola
Russia Hughes N Yakutia
Russia Jacoby Lukunska
Russia MacDonald Lower Lena
Russia Schweingruber Adycha
Sweden Axelson Bjorbo
Sweden Linderholm Nonshagen
Sweden Linderholm Scots Pine
Sweden Linderholm Skuleskogen
Sweden Linderholm Tannsjo
USA Calkin Cordova
USA Calkin Ellsworth
USA Calkin Exit
USA Calkin Miners
USA Calkin Rock Glacier
USA Calkin Tebenkof Glacier
USA Calkin Wittier Canal
USA Calkin Wolverine Glacier
USA Graybill BC Pine
USA Jacoby Sheenjek River
USA Wiles Lower Twin
The following table shows the cross correlation of the annual normalised tree width:
Canada Norway Russia Sweden USA
0.27 0.44 0.07 0.36
Norway 0.27
0.29 0.19 0.27
Russia 0.44 0.29
0.10 0.12
Sweden 0.07 0.19 0.10
USA 0.36 0.27 0.12 0.06
It is interesting to note that the data from all five countries show the increase in temperature that was observed from 1910 to 1945 and the fall from 1945 to 1975 whereas there is less consistency for earlier periods. We believe that it has not been previously reported but is it possible that with time the new outer rings compress the older inner rings thereby weakening their signal.

Figure 1: Northern Hemisphere Tree Ring Widths
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Figure 2: Tree Ring Widths - Canada
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Figure 3: Tree Ring Widths - Norway
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Figure 4: Tree Ring Widths - Sweden
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Figure 5: Tree Ring Widths - Russia
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Figure 6: Tree Ring Widths - USA
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