Klimawandel und der Einfluss auf die Frühlingsphänologie | Climate change and its influence on spring phenology

Spring season (March–May) temperature trends show an increase in most regions of the world. In Europe, the spring temperatures important to plant physiology were the warmest during the decade 1997–2006 with respect to the past 500 years. A temperature increase of 1 °C would lead to an earlier onset of spring phenological phases of 2 to 10 days depending on the species and the region. A phenological multi-species index for Switzerland which includes several plant species is shown to be a suitable tool to describe Swiss spring variability over the past four decades. The index shows a mean trend of 1.5 days/decade from 1965–2002. The 280-year long series of the flowering of the cherry tree represents the index-variability of the past 40 years and gives the unique possibility to assess climate impact on spring phenological variability during past centuries.