Climate changes and forest ecosystems: a multivariate classification of meteorological conditions (1981–2012) in Castelporziano, central Italy

Identifying signals of climate change and increased meteorological variability requires analytical tools suited to explore large data sets based on multidimensional measures. By focusing primarily on thermometric and precipitation regimes, the present study develops a multivariate classification of 12 climate variables recorded over a period of 32 years (1981–2012) in Castelporziano forest (Rome, central Italy). A moderate reduction in annual rainfall together with a marked increase in maximum and minimum air temperature was observed in Castelporziano along the study period. Principal component analysis distinguished ‘dry’ and ‘hot’ years (concentrated in the last decade) from ‘wet’ and ‘cold’ years, more common in the 1980s and the 1990s. Our results underline the increased unpredictability of Mediterranean dry spells possibly due to the higher climate variability in the drier season. Policies for climate change adaptation and mitigation are increasingly requested to integrate short- and medium-term strategies aimed at the most effective use of natural resources and the conservation of relict natural ecosystems surrounding urban areas.