HyMeX: A 10-Year Multidisciplinary Program on the Mediterranean Water Cycle

TLDR

The Mediterranean faces severe water‑cycle challenges—shortages, floods, extreme winds, and ice/snow storms—yet gaps remain in understanding its water budget, air–sea interactions, and precipitation impacts on aquifers, rivers, soils, and vegetation. HyMeX is a 10‑year international program designed to advance knowledge of the Mediterranean water cycle across land, sea, and atmosphere, improve process‑based hydrometeorological and regional climate models, and evaluate social and economic vulnerability to support policy adaptation to climate change. The program implements coordinated observations and experiments over a decade, integrating multi‑compartment measurements and model development to capture variability at multiple time and spatial scales and link scientific results to policy needs.

Abstract

The Mediterranean countries are experiencing important challenges related to the water cycle, including water shortages and floods, extreme winds, and ice/snow storms, that impact critically the socioeconomic vitality in the area (causing damage to property, threatening lives, affecting the energy and transportation sectors, etc.). There are gaps in our understanding of the Mediterranean water cycle and its dynamics that include the variability of the Mediterranean Sea water budget and its feedback on the variability of the continental precipitation through air–sea interactions, the impact of precipitation variability on aquifer recharge, river discharge, and soil water content and vegetation characteristics specific to the Mediterranean basin and the mechanisms that control the location and intensity of heavy precipitating systems that often produce floods. The Hydrological Cycle in Mediterranean Experiment (HyMeX) program is a 10-yr concerted experimental effort at the international level that aims to advance the scientific knowledge of the water cycle variability in all compartments (land, sea, and atmosphere) and at various time and spatial scales. It also aims to improve the processes-based models needed for forecasting hydrometeorological extremes and the models of the regional climate system for predicting regional climate variability and evolution. Finally, it aims to assess the social and economic vulnerability to hydrometeorological natural hazards in the Mediterranean and the adaptation capacity of the territories and populations therein to provide support to policy makers to cope with water-related problems under the influence of climate change, by linking scientific outcomes with related policy requirements.