Figures 1-6 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 were:
|
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 |
|
Canada |
- |
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 |
- |
0.06 |
|
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.
