TREE-RING SIGNATURES AND WEATHER ANOMALIES (OAK STAND GUTTENBERGER FOREST, WEATHER STATION WURZBURG)

We introduce a method for dendroclimatological interpretation of tree-ring chronologies from regions of optimum ecological conditiones (deciduous forests of southern German lowland). The correlation between tree-ring signature years of oak and weather anomalies have been studied in a site near Wurzburg. The results have been compared with those of multiple regression analyses. With this method we investigated the correlation of the tree-ring variations with monthly records of 45 meteorological parameter measured over the period from 1936 to 1986 in Wurzburg. According to the signature test most of the significant oak tree-ring variations can be explained by the occurence of typical patterns of weather anomalies as derived from the climatic data record. The multiple regression analyses rather indicate tendencies of the tree-growth/weather relation. They especially show the influence of seasonal variations in the meteorological data. Combining the results of the signature test and the multiple regression analysis we have evidence, that our tree-ring signature/weather anomaly model can be used for a verification of time series of past climate which we have derived from historical wine and grain yield data records of southern German regions.