Observed climate changes in Croatia Climate change scenario

3. Impact of climate variations and change on plants and on wildfire danger
3.1. Impact of climate variations and change on plants
Research of climate change impact on plants is based on an idea that plants are the first
that react to weather and climate change, for which purpose the phenological data are suitable
for monitoring development phases of certain plant species. Results of linear trends of long-term
phenological phases of common lilac, apple and olive trees from phenological stations Daruvar,
Zagreb, Gospić, Rab and Hvar (Fig. 3-1), mostly from the period 1961.-2008., are indicated
below. The stations were chosen in order to cover basic climate types in Croatia: continental,
mountainous and Mediterranean, as well as the city of Zagreb.
Weather conditions of the last years less and less follow known annual and seasonal cycles
and there are more and more extreme weather events not following average states. Thus, for
example, during 2007, due to extremely warm winter and spring, phenophases occurred much
earlier. Analyses of linear trends of olive tree phenophases along the Adriatic coast and islands,
as well as forest trees and fruit trees phenophases in mountainous Croatia within the last 50
years indicated significant earlier beginning of their flowering (2–4 days/10 years) as a result of
significant increase of spring air temperature values in this area.
Figure 3-1. Position of selected meteorological and phenological stations in Croatia
In the Croatian inland vegetation period for the majority of plants begins in March or April.
The beginning of common lilac leaf unfolding in Zagreb is on 26 March in average, while in
Daruvar on 1 April 1 st (Table 3-1). Naturally, the periods are changed from year to year, so the
range between the latest and the earliest date can be even month and a half.
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