Introduction

Abstract

In a usual climate atlas, the reader finds average charts of the various climate elements (temperature, precipitation, etc.) or charts of any climate classification which again represent average aspects. Thus, the impression arises that climate, in contrast to weather, is more or less constant. Even the reference period (time interval which is covered by the climatic data) is often not specified. In reality, climate varies on all scales of time and space (Mitchell et al., 1966; Schönwiese, 1994). To realize this fact in detail, however, and to survey it clearly, are not easy. This is why all measurements imply errors or uncertainly ranges, respectively, and even without errors the variation behaviour of climate is so complicated that proper statistical methods are needed to take into account the various aspects of climate variability and to separate the various components of climate variations.