Mean and extreme precipitation regime in North and Central Italy – between stability and change

Authors

  • Simone Gabriele Parisi DIAGRAM S.p.A, Via Cavicchini 9, 44037 Jolanda di Savoia (FE), Italy
  • Gianluca Alimonti INFN, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy https://orcid.org/0000-0002-7128-9046
  • Luigi Mariani DICATAM, Università degli Studi di Brescia, Via Branze, 43, 25123 Brescia

DOI:

https://doi.org/10.36253/ijam-3315

Keywords:

extreme events, precipitation climatology, gridded precipitation dataset, frequency and intensity trends

Abstract

The work was carried out on the gridded precipitation dataset of the ARCIS consortium (hereafter ARCIS) that was produced spatializing a daily dataset of 1762 stations coming from 7 regions of Northern Italy and three regions of Central Italy for the period 1961-2023, with a pixel of 4.7 x 4.7 km. The mean yearly precipitation value from 1961 to 2023 shows a large interannual variability. On the other hand, the trend in frequency and intensity of extreme events (daily events above 50 mm) exhibit high space and time variability. Highlighting areas with significant or not significant trends is crucial for designing hydraulic infrastructures and managing the impacts of natural risks such as floods and landslides. Overall, results reveal that 83% and 86% of the areas do not show significant increases respectively in frequency and intensity while 11% and 15% show significant increases and 2% and 3% show significant decreases. Moreover, the spatial pattern of the areas affected by increasing frequency and intensity, highlights the presence of some regions characterized by increasing trend in North Italy at the beta mesoscale (20-200 km) which is the theatre of phenomena like mesocyclones or low-level jets. Finally, it should be noted that the 1991-2023 analysis of seasonal variations highlights a frequency increase of extreme phenomena in autumn (from October to December with a more marked increase in November), a weak decrease from January to April and a marked decrease in August. These variations can be interpreted as the result of the interaction of the synoptic circulation with mesoscale effects triggered by orography and sea surface temperature.

References

Alpert P., Ben-Gai T., Baharad A., Benjamini Y., Yekutieli D., Colacino M., Diodato L., Ramis C., Homar V., Romero R., Michaelides S., Manes A., 2002. The paradoxical increase of Mediterranean extreme daily rainfall in spite of decrease in total values. Geophysical Research Letters 29(11): 301-314

Antolini G., Auteri L., Pavan V., Tomei F., 2015. A daily high-resolution gridded climatic data set for Emilia-Romagna, Italy, during 1961-2010. International Journal of Climatology, August 2015, https://doi.org/10.1002/joc.4473

Barton Y., Rivoire P., Koh J., Ali M. Kopp J., Martius O., 2022. On the temporal clustering of European extreme precipitation events and its relationship to persistent and transient large-scale atmospheric drivers. Weather and Climate Extremes, Volume 38, December 2022, 100518.

Bassi M., Colombino G., Cremonini R., Masciocco L., 2011. Analisi delle piogge estreme in Piemonte. Atti del convegno Le modificazioni climatiche ed i rischi naturali, 53-58.

Bauer, V. M., & Scherrer, S. C. (2024). The observed evolution of sub-daily to multi-day heavy precipitation in Switzerland. Atmospheric Science Letters 25(9): e1240. https://doi.org/10.1002/asl.1240

Bonacci, O.; Vrsalovi´c, A., 2022. Differences in Air and Sea Surface Temperatures in the Northern and Southern Part of the Adriatic Sea. Atmosphere 2022, 13: 1158. https://doi.org/10.3390/atmos13071158

Brunetti M., Caloiero T., Coscarelli R., Gullà G., Nanni T., Simolo C., 2010. Precipitation variability and change in the Calabria region (Italy) from a high resolution daily dataset. https://doi.org/10.1002/joc.2233

Carniel C.E., Ricchi A., Ferretti R., Curci G., Miglietta M.M., Reale M., Serafini P., Wellmeyer E.D., Davolio S., Zardi D., Kantha L., 2024. A high-resolution climatological study of explosive cyclones in the Mediterranean region: Frequency, intensity and synoptic drivers. Q J R Meteorol Soc. 150: 5561–5582.

Cati L., 1981. Idrografia e idrologia del Po, Roma, Istituto Poligrafico e Zecca dello Stato, 310 pp.

De Martin F., Davolio S., Miglietta M.M., Levizzani V., 2024. A Conceptual Model for the Development of Tornadoes in the Complex Orography of the Po Valley. Monthly Weather Review 152(6): 1357-1377.

Doswell III C.A., Brooks H.E., Maddox R.A., 1996. Flash Flood Forecasting: An Ingredients-Based Methodology. Weather and forecasting 11(4): 560-581.

Fatichi S., Caporali E., 2009. A comprehensive analysis of changes in precipitation regime in Tuscany. International Journal of Climatology 29(13): 1883-1893.

Franzke C.L.E., Barbosa S., Blender R., Fredriksen H.-B., Laepple T., Lambert F., 2020. The structure of climate variability across scales. Reviews of Geophysics 58: e2019RG000657. https://doi.org/10.1029/2019RG000657

Frei C., Schär C., 1998. A precipitation climatology of the Alps from high-resolution rain-gauge observations. Int. J. Clim. 18(8): 873-900.

Gilbert R.O, 1987. Statistical methods for environmental pollution monitoring. Van Nostrand Reinhold, New York, 321 pp.

Giustini F., Brilli M. and Patera A., 2016. Mapping oxygen stable. isotopes of precipitation in Italy. Journal of Hydrology: Regional Studies 8(2016): 162-181.

Grazzini F., Craig G.C., Keil C.,Antolini G., Pavan V., 2019. Extreme precipitation events over northern Italy. Part I: A systematic classification with machine-learning techniques. Q J R Meteorol Soc. 146: 69-85. https://doi.org/10.1002/qj.3635

Heimo A. , Konzelmann T., 2003. SwissMetNet: Renewal of the Swiss Meteorological Networks. Proceedings of the International Conference on the Experiences with Automatic Weather Stations, Torremolinos, Spain, 19-21 February, 2003.

IPCC, 2023. Sections. In: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, pp. 35-115, https://doi.org/10.59327/IPCC/AR6-9789291691647

Isotta F.A., Frei C., Weilguni V., Percec Tadic M., Lassegues P., Rudolf B., Pavan V., Cacciamani C., Antolini G., Ratto S.M., Munari M., Micheletti S., Bonati V., Lussana C., Ronchi C., Panettieri E., Marigo G., Vertacnik G., 2013. The climate of daily precipitation in the Alps: development and analysis of a high-resolution grid dataset from pan-Alpine rain-gauge data. Int J Climatol. 34(5): 1657-1675.

Katz J., 2023. Concepts across the Sciences: Stability and Change, USA Library of congress, https://blogs.loc.gov/teachers/2023/03/concepts-across-the-sciences-stability-and-change/

Khodayar S., Kalthoff N. , Kottmeier C. ,2018. Atmospheric conditions associated with heavy precipitation events in comparison to seasonal means in the western Mediterranean region. Climate Dynamics 51(3): 951-967.

Lavers D.A. , Villarini G., 2013. The nexus between atmospheric rivers and extreme precipitation across Europe. Geophysical Research Letters 40: 3259-3264. https://doi.org/10.1002/grl.50636.

Lavers D.A. , Villarini G., 2015. The relationship between daily European precipitation and measures of atmospheric water vapour transport. International Journal of Climatology 35: 2187-2192. https://doi.org/10.1002/joc.4119

Lebon E., Dumas V., Pieri P., Schultz H.R. , 2003. Modelling the seasonal dynamics of the soil water balance of vineyards. Funct. Plant Biol. 30: 699-710.

Libertino A., Macchia S., Claps P., 2016. Nubifragi eccezionali in Italia: analisi preliminare di rilevanza sugli eventi 1920-2000, Atti del XXXV Convegno Nazionale di Idraulica e Costruzioni Idrauliche, Bologna, 14-16 Settembre 2016, 4 pp. (in Italian)

Libertino A., Ganora D., Claps P., 2018 Technical note: Space–time analysis of rainfall extremes in Italy - clues from a reconciled dataset. Hydrol. Earth Syst. Sci. 22: 2705-2715. https://doi.org/10.5194/hess-22-2705-2018

Libertino A., Ganora D., Claps P., 2019. Evidence for increasing rainfall extremes remains elusive at large spatial scales: the case of Italy. Geophysical Research Letters https://doi.org/10.1029/2019GL083371

Lukasova V., Varsova S., Onderka M., Bilcik D., Buchholcerov A., Nejedl P., 2024. Continuity of long-term climate data series after the transition from manual to automatic weather station. Contributions to Geophysics and Geodesy 54(3): 251-266.

Mallakpour I., Sadeghi M., Mosaffa H., Akbari Asanjan A., Sadegh M., Nguyen P., Sorooshian S., and AghaKouchak A., 2022. Discrepancies in changes in precipitation characteristics over the contiguous United States based on six daily gridded precipitation datasets. Weather Clim. Extrem. 36: 100433. https://doi.org/10.1016/j.wace.2022.100433

Mariani L., Parisi S., 2013. Extreme rainfalls in the Mediterranean area, in Storminess and environmental changes: climate forcing and responses in Mediterranean region. Diodato and Bellocchi (Eds.), Springer.

Mariani L. , Parisi S. , Cola G. , Failla O., 2012. Climate change in Europe and effects on thermal resources for crops. International Journal of Biometeorology 56: 1123-1134. https://doi.org/10.1007/s00484-012-0528-8

Mori A., 1964. Carta delle precipitazioni medie annue in Italia (trentennio 1921-1950), CNR, Istituto di geografia dell’Università di Pisa, Roma, Cartografia Riccardi (in Italian).

Nygard T., Papritz L., Naakka T., Vihma T., 2023. Cold wintertime air masses over Europe: where do they come from and how do they form? Weather Clim. Dynam. 4: 943-961. https://doi.org/10.5194/wcd-4-943-2023

Parisi S.G., Mariani L., Cola G., 2014. Extreme rainfall in the Lombardy region. Italian Journal of Agrometeorology 1: 19-28.

Pavan V., G.Antolini, G.Agrillo, L. Auteri, R. Barbiero, V. Bonati, F. Brunier, C.Cacciamani, O. Cazzuli, A. Cicogna, C. De Luigi, L. Maraldo, G. Marigo, R. Millini, E. Panettieri, S. Ratto, C. Ronchi, S. Saibanti, A. Sulis, F. Tomei, R. Tomozeiu, I. Torlai, G. Villani, 2013. The ARCIS Project. Italian Journal of Agrometeorology 2: 51-55.

Pavan V., Antolini G., Barbiero R., Berni N., Brunier F. Cacciamani C. Cagnati A., Cazzuli O., Cicogna A., De Luigi C., Di Carlo E., Francioni M., Maraldo L., Marigo G., Micheletti S. Onorato L., Panettieri E., Pellegrini U., Pelosini R., Piccinini D., 2018. High resolution climate precipitation analysis for north-central Italy, 1961–2015’. Climate Dynamics 52: 1-19.

Pinna S., 2014. La falsa teoria del clima impazzito, 158 pp. (in italian)

Pinto J.G., Ulbrich S., Parodi A., Rudari R., Boni G., Ulbrich U., 2013. Identification and ranking of extraordinary rainfall events over northwest Italy: the role of Atlantic moisture. Journal of Geophysical Research: Atmospheres 118: 2085-2097. https://doi.org/10.1002/jgrd.50179

Piotrowicz K., Ciaranek D., 2020. A selection of weather type classification systems and examples of their application. Theoretical and Applied Climatology 140: 719-730. https://doi.org/10.1007/s00704-020-03118-2

Pucik T., 2024. Meteorological analysis of extreme flash flood situation in the Valencia region, https://www.essl.org/cms/meteorological-analysis-of-extreme-flash-flood-situation-in-the-valencia-region/ (site visited at 27 June 2025)

Raveh-Rubin S., Wernli H., 2015. Large-scale wind and precipitation extremes in the Mediterranean – a climatological analysis for 1979-2012. Quarterly Journal of the Royal Meteorological Society 141: 2404-2417. https://doi.org/10.1002/qj.2531

Reid P.C., Hari R.E., Beaugrand G., Livingstone D.M., Marty C., Straile D., Barichivich J., Goberville E., Adrian R., Aono Y., Brown R., Foster J., Groisman P., Hélaouët P., Hsu H.H., Kirby R., Knight J., Kraberg A., Li J., Lo T.T., Myneni R.B., North R.P., Pounds J.A., Sparks T., Stübi R., Tian Y., Wiltshire K.H., Xiao D., Zhu Z., 2015. Global impacts of the 1980s regime shift. Glob Chang Biol. 22(2): 682-703. https://doi.org/10.1111/gcb.13106

Rotunno R., Houze R.A., 2007. Lessons on orographic precipitation from the Mesoscale Alpine Programme. Q. J. R. Meteorol. Soc. 133: 811-830.

Silvestri L., Saraceni M., Bongioannini Cerlini P., 2022. Quality management system and design of an integrated mesoscale meteorological network in Central Italy. Meteorological Applications 29: e2060. https://doi.org/10.1002/met.2060

Skipper S., Perktold J., 2010. Statsmodels: Econometric and statistical modeling with python. Proceedings of the 9th Python in Science Conference.

Sun Q., Miao C., Duan Q., Ashouri H.,Sorooshian S., Hsu K.-L., 2017. A review of global precipitation data sets: Data sources, estimation, and inter-comparisons. Reviews of Geophysics 56: 79-107. https://doi.org/10.1002/2017RG000574

Sun Q., Zhang X., Zwiers F., Westra S., Alexander L.V., 2021. A Global, Continental, and Regional Analysis of Changes in Extreme Precipitation. Journal of Climate 1 Jan 2021: 243-258. https://doi.org/10.1175/JCLI-D-19-0892.1

Winschall A., Sodemann H., Pfahl S. , Wernli H., 2014. How important is intensified evaporation for Mediterranean precipitation extremes? Journal of Geophysical Research: Atmospheres 119: 5240-5256. https://doi.org/10.1002/2013JD021175

World Meteorological Organization, 2021a. Updated 30-year reference period reflects changing climate, https://wmo.int/media/news/updated-30-year-reference-period-reflects-changing-climate (site visited the 3 January 2025)

World Meteorological Organization, 2021b. Guide to meteorological instruments and methods of observation (WMO guide n. 8), Geneva, CH, https://community.wmo.int/en/activity-areas/imop/wmo-no_8

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Published

2025-09-29

How to Cite

Parisi, S. G., Alimonti, G., & Mariani, L. (2025). Mean and extreme precipitation regime in North and Central Italy – between stability and change . Italian Journal of Agrometeorology, (2), 3–22. https://doi.org/10.36253/ijam-3315

Issue

No. 2 (2025)

Section

RESEARCH ARTICLES

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