Vicente‐Serrano et al. (2025) High temporal variability not trend dominates Mediterranean precipitation

Identification

• Journal: Nature
• Year: 2025
• Date: 2025-03-12
• Authors: Sergio M. Vicente‐Serrano, Yves Tramblay, Fergus Reig, José Carlos González Hidalgo, Santiago Beguerı́a, Michele Brunetti, Ksenija Cindrić Kalin, Leonardo Patalen, Aleksandra Kržič, Piero Lionello, Miguel M. Lima, Ricardo M. Trigo, Ahmed El Kenawy, Ali Salem Eddenjal, Murat Türkeş, Aristeidis Koutroulis, Veronica Manara, Maurizio Maugeri, Wafae Badi, Shifa Mathbout, Renato Bertalanič, Lilia Bocheva, İsmail Dabanlı, Alexandru Dumitrescu, Brigitte Dubuisson, Salah Sahabi Abed, Fayez Abdulla, Abbas Fayad, S. Hodžić, Mirjana Ivanov, Иван Радевски, Dhais Peña‐Angulo, Jorge Lorenzo‐Lacruz, Fernando Domínguez‐Castro, Luis Gimeno‐Sotelo, Ricardo García‐Herrera, Magí Franquesa, Amar Halifa‐Marín, María Adell-Michavila, Iván Noguera, David Barriopedro, José M. Garrido‐Pérez, César Azorín-Molina, Miguel Andres-Martin, Luís Gimeno, Raquel Nieto, María Carmen Llasat, Yannis Markonis, Rabeb Selmi, Soumaya Ben Rached, Slavica Radovanović, Jean-Michel Soubeyroux, Aurélien Ribes, Mohamed Elmehdi Saidi, Siham Bataineh, El Mahdi El Khalki, S. M. Robaa, Amina Boucetta, Karam Alsafadi, Nikοs Mamassis, Safwan Mohammed, Beatriz Fernández‐Duque, Sorin Cheval, Sara Moutia, Aleksandra Stevkov, Silvana Stevkova, M. Y. Luna, Vera Potopová
• DOI: 10.1038/s41586-024-08576-6

Research Groups

• Instituto Pirenaico de Ecología, Consejo Superior de Investigaciones Científicas (IPE-CSIC), Zaragoza, Spain
• Laboratorio de Climatología y Servicios Climáticos (LCSC), CSIC– Universidad de Zaragoza, Zaragoza, Spain
• Espace Dev, Univ. de Montpellier IRD, Montpellier, France
• Departamento de Geografía, Universidad de Zaragoza, Zaragoza, Spain
• Instituto Universitario Ciencias Ambientales (IUCA), Zaragoza, Spain
• Estación Experimental de Aula Dei (EEAD-CSIC), Consejo Superior de Investigaciones Científicas, Zaragoza, Spain
• National Research Council – Institute of Atmospheric Sciences and Climate (CNR-ISAC), Bologna, Italy
• Croatian Meteorological and Hydrological Service, Zagreb, Croatia
• Republic Hydrometeorological Service of Serbia, Belgrade, Serbia
• Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
• Faculdade de Ciências, Instituto Dom Luiz (IDL), Universidade de Lisboa, Lisbon, Portugal
• And numerous other national meteorological services and research institutions across 27 Mediterranean countries.

Short Summary

This study reveals that Mediterranean precipitation has largely remained stationary from 1871 to 2020, with significant multi-decadal and interannual variability, and attributes observed trends primarily to atmospheric dynamics rather than anthropogenic forcing. This conclusion is based on the most comprehensive dataset available for the region, encompassing over 23,000 stations.

Objective

• To conduct a comprehensive assessment of long-term precipitation dynamics in the Mediterranean region, utilizing an unprecedented observational dataset, to reconcile conflicting perspectives on historical precipitation trends.
• To determine whether observed precipitation changes are primarily driven by atmospheric circulation patterns (internal variability) or anthropogenic influences.

Study Configuration

• Spatial Scale: The entire Mediterranean region, encompassing 27 countries, utilizing data from over 23,000 meteorological stations.
• Temporal Scale: 150 years, from 1871 to 2020, with analyses also conducted for sub-periods (e.g., 1901–2020, 1931–2020, 1951–2020, 1981–2020).

Methodology and Data

• Models used:
  • Statistical: Nonparametric Mann–Kendall test (for trend signal and significance), Theil–Sen (TS) regression (for magnitude of change), stepwise regression models (to disentangle atmospheric influence).
  • Climate Models: Coupled Model Intercomparison Project Phase 5 (CMIP5) and Coupled Model Intercomparison Project Phase 6 (CMIP6) historical and future scenario simulations.
• Data sources:
  • Primary: A comprehensive dataset of 10,238,736 monthly precipitation records from 23,609 stations across 27 Mediterranean countries, derived from over 300 million daily observations. Data underwent rigorous quality control, reconstruction, and homogeneity correction.
  • Public Databases: Global Historical Climatology Network (GHCN), European Climate Assessment & Dataset (ECA&D), Global Surface Summary of the Day (GSOD) for comparison and gap-filling in some areas.
  • Atmospheric Indices: North Atlantic Oscillation (NAO), Mediterranean Oscillation (MO), and regional atmospheric circulation indices (storm frequency, occurrence of blocks and ridges).

Main Results

• Mediterranean precipitation has largely remained stationary from 1871 to 2020, characterized by significant multi-decadal and interannual variability rather than a consistent long-term trend.
• While some periods and subregions show statistically significant trends, these are primarily attributed to atmospheric dynamics and internal climate variability.
• Regional average annual precipitation showed a decline of less than 3% over the entire 1871–2020 period, and a 5% decrease from 1951, but these long-term trends were not statistically significant.
• Winter precipitation exhibited declining trends of 10.2% (1931–2020) and 13.2% (1951–2020), but these were not statistically significant over longer (1871, 1901) or shorter (1981) periods.
• Characteristics of meteorological droughts (duration and magnitude) also displayed a consistent stationary pattern.
• Atmospheric circulation indices (NAO, MO, and regional drivers) explain a significant portion of annual precipitation variability (32-39.1% for NAO/MO alone, over 68% when regional mechanisms are included for short-term annual models), with the residuals of these models showing largely stationary behavior.
• Comparison with CMIP5 and CMIP6 model simulations reveals substantial agreement with observed precipitation trends, with models also indicating a prevalence of statistically non-significant historical precipitation trends. CMIP6 models show improved performance in replicating observed trends compared to CMIP5.
• The Mediterranean region is experiencing increasing climatic aridity, primarily driven by an increase in atmospheric evaporative demand due to rising temperatures, a process independent of the observed precipitation dynamics.

Contributions

• Established the most comprehensive and high-quality observational precipitation dataset for the Mediterranean region to date, spanning 150 years and over 23,000 stations, by overcoming data-sharing restrictions through an innovative code-sharing approach.
• Provided a robust, long-term assessment that challenges the prevailing perception of a widespread drying trend in Mediterranean precipitation, demonstrating long-term stationarity and attributing observed trends to internal atmospheric variability.
• Reconciled observed historical precipitation trends with CMIP5 and CMIP6 model simulations, showing consistency in the prevalence of non-significant trends, thus refining the understanding of model performance for the region.
• Highlighted the critical importance of maintaining traditional meteorological station networks and developing regional observation databases, particularly in data-scarce regions, for accurate climate change assessment.

Funding

• Spanish Ministry of Science and the FEDER (research projects TED2021-129152B-C41 and PID2022-137244OB-I00)
• i-LINK 2021 programme by CSIC (MEHYDRO, LINKB20080)
• Ministry for the Ecological Transition and the Demographic Challenge (MITECO) and the European Commission NextGenerationEU (Regulation EU 2020/2094) (project CSC2300000, through CSIC’s Interdisciplinary Thematic Platform Clima (PTI-Clima))
• ESA contract no. 4000145543/24/I-LR (GLANCE ‘AGricultural Land AbandoNment and ClimatE change impacts on the water, energy and vegetation carbon cycles in the Mediterranean region’)
• IRD IRN RHYMA (Y.T.)
• Istanbul Technical University (ITU) (MGA-2023-44196, I.D.)
• PRIMA-funded project REACT4MED (GA 2122), supported by Horizon 2020 (A. Koutroulis)
• UNESCO ICIREWARD centre (workshop in November 2022 in Montpellier)

Citation

@article{VicenteSerrano2025High,
  author = {Vicente‐Serrano, Sergio M. and Tramblay, Yves and Reig, Fergus and Hidalgo, José Carlos González and Beguerı́a, Santiago and Brunetti, Michele and Kalin, Ksenija Cindrić and Patalen, Leonardo and Kržič, Aleksandra and Lionello, Piero and Lima, Miguel M. and Trigo, Ricardo M. and Kenawy, Ahmed El and Eddenjal, Ali Salem and Türkeş, Murat and Koutroulis, Aristeidis and Manara, Veronica and Maugeri, Maurizio and Badi, Wafae and Mathbout, Shifa and Bertalanič, Renato and Bocheva, Lilia and Dabanlı, İsmail and Dumitrescu, Alexandru and Dubuisson, Brigitte and Abed, Salah Sahabi and Abdulla, Fayez and Fayad, Abbas and Hodžić, S. and Ivanov, Mirjana and Радевски, Иван and Peña‐Angulo, Dhais and Lorenzo‐Lacruz, Jorge and Domínguez‐Castro, Fernando and Gimeno‐Sotelo, Luis and García‐Herrera, Ricardo and Franquesa, Magí and Halifa‐Marín, Amar and Adell-Michavila, María and Noguera, Iván and Barriopedro, David and Garrido‐Pérez, José M. and Azorín-Molina, César and Andres-Martin, Miguel and Gimeno, Luís and Nieto, Raquel and Llasat, María Carmen and Markonis, Yannis and Selmi, Rabeb and Rached, Soumaya Ben and Radovanović, Slavica and Soubeyroux, Jean-Michel and Ribes, Aurélien and Saidi, Mohamed Elmehdi and Bataineh, Siham and Khalki, El Mahdi El and Robaa, S. M. and Boucetta, Amina and Alsafadi, Karam and Mamassis, Nikοs and Mohammed, Safwan and Fernández‐Duque, Beatriz and Cheval, Sorin and Moutia, Sara and Stevkov, Aleksandra and Stevkova, Silvana and Luna, M. Y. and Potopová, Vera},
  title = {High temporal variability not trend dominates Mediterranean precipitation},
  journal = {Nature},
  year = {2025},
  doi = {10.1038/s41586-024-08576-6},
  url = {https://doi.org/10.1038/s41586-024-08576-6}
}