Theoretical and Applied Climatology

, Volume 114, Issue 1–2, pp 39–54 | Cite as

Functional clustering for Italian climate zones identification

  • E. Di GiuseppeEmail author
  • G. Jona Lasinio
  • S. Esposito
  • M. Pasqui
Original Paper


This work presents a functional clustering procedure applied to meteorological time series. Our proposal combines time series interpolation with smoothing penalized B-spline and the partitioning around medoids clustering algorithm. Our final goal is to obtain homogeneous climate zones of Italy. We compare this approach to standard methods based on a combination of principal component analysis and Cluster Analysis (CA) and we discuss it in relation to other functional clustering approaches based on Fourier analysis and CA. We show that a functional approach is simpler than the standard methods from a methodological and interpretability point of view. Indeed, it becomes natural to find a clear connection between mathematical results and physical variability mechanisms. We discuss how the choice of the basis expansion (splines, Fourier) affects the analysis and propose some comments on their use. The basis for classification is formed by monthly values of temperature and precipitation recorded during the period 1971–2000 over 95 and 94 Italian monitoring stations, respectively. An assessment based on climatic patterns is presented to prove the consistency of the clustering and a comparison of results obtained with different methods is used to judge the functional data approach.


Climate zones Functional clustering Physical connection 



This work has been developed within the context of Agroscenari project “Adaptation of Agricultural Management to climate change” funded by the Italian Ministry of Agriculture. The authors would like to thank two anonymous referees for the useful comments that helped in considerably improving the paper and Prof. M. MAugeri for his suggestions.


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Copyright information

© Springer-Verlag Wien 2012

Authors and Affiliations

  • E. Di Giuseppe
    • 1
    • 2
    Email author
  • G. Jona Lasinio
    • 2
  • S. Esposito
    • 1
  • M. Pasqui
    • 3
  1. 1.Research Unit for Climatology and Meteorology Applied to Agriculture (CRA-CMA)Consiglio per la ricerca e la sperimentazione in agricolturaRomeItaly
  2. 2.Department of Statistics (Uniroma1-Dss)University of Rome La SapienzaRomeItaly
  3. 3.Institute of Biometeorology (CNR-Ibimet)National Research CouncilRomeItaly

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