Changes in European spring phenology

The European phyto-phenological database of the EU 5th Framework project `POSITIVE' facilitated an examination of the rate and spatial pattern of changes in spring phenology across Europe. This database was collected, evaluated and composed from different national databases of Eastern and Western Europe covering the time period 1951-1998. Results show that spring phases have advanced four weeks in Western and Central Europe, and have been delayed up to two weeks in Eastern Europe. Western European spring starts earlier because of the intensive flow of warmer Atlantic air masses; the Eastern part of Europe has a different phenological rhythm and trends, that can be explained by the influence of the Siberian high. The highest rate of significant (p < 0.05) phenological change (-0.3 to -0.4 days per year) occurs in the Western Europe and Baltic Sea regions for early spring phases of hazel and colts-foot. Spring phases of birch, apple and lilac, and summer phases, such as the flowering,of linden, tend to occur earlier with an average rate of -0.1 to 0.3 days per year. Copyright (C) 2002 Royal Meteorological Society.