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Medicanes, for Mediterranean hurricanes, are mesoscale cyclones with morphological and physical characteristics similar to tropical cyclones. Although less intense, smaller, and rarer than their Atlantic counterparts, medicanes are very hazardous events threatening islands and continental coasts within the Mediterranean Sea. The latest strong episode, Medicane Ianos (September 2020), resulted in severe damages in Greece and several casualties. This work investigates the oceanic response to these extreme events along the Mediterranean coasts under present‐day and future (late 21st century) climate conditions. To this end, a coupled hydrodynamic‐wave model is used to simulate both storm surges and wind‐waves generation and propagation in the Mediterranean Sea at high resolution (∼2 km) along the coastlines. A data set of thousands of medicanes synthetically generated from 20 global climate models and two atmospheric reanalyses is used to derive the atmospheric forcing fields. Regional coastal hazards assessment is performed for the present and future climates. For the first period, highest medicane‐induced waves are found in the central and the southwest part of the western Mediterranean, while greatest storm surges are found in the Adriatic Sea and regions characterized by wide and gently sloping continental shelves. Results obtained for future changes show amplitudes generally smaller than the associated uncertainty due to limited agreement among models (especially for coastal elevation). Though, model consensus is reached (60–75%) and relative intensity change is significant (10–20%) at some locations (e.g., 1 m increase of medicane‐induced significant wave height on average for south coasts of Sicilia). Plain Language Summary: Mediterranean hurricanes, medicanes, are tropical‐like cyclones generated in the Mediterranean basin that differ from their counterpart in the Atlantic in their smaller size and intensity. They rarely exceed 400 km of diameter and last generally 24–48 hr, unusually reaching intensities of category 1 hurricanes. A medicane is characterized by a warm core accompanied by thunderstorms, heavy rain, but also strong cyclonic winds (counter‐clockwise rotation) that are responsible for costly damages and often result in casualties. Furthermore, medicanes pose serious threats to coastal populations due to the storm surges, that is, the raising of the sea surface due to low atmospheric pressure, and to the combined effects of waves and winds along the coasts. This study investigates the coastal hazards induced by medicanes over the entire basin. To do so, we used a hydrodynamic and wave coupled model to simulate the generation and propagation of storm surges and wind‐waves over the Mediterranean Sea under the forcing of a set of thousands of synthetic medicanes that statistically describe the medicane climate for the present and future period (end of 21st century). Our results identify the most exposed coastal areas and quantify the current and projected return levels for waves and storm surges. Key Points: Mediterranean hurricanes (medicanes) generate largest wind‐waves (exceeding 10 m) in the central and the southwest part of the western basinWide and gently sloping continental shelves favor the generation of storm surges under medicane forcing with 100‐year return levels over 1 mProjected changes medicane‐induced coastal hazards are uncertain due to limited multimodel consensus, with some local exceptions [ABSTRACT FROM AUTHOR]

Most of the nature‐related economic costs and human losses in many regions of Europe are due to extreme weather events such as heat waves, cold spells, persistent droughts, heavy precipitation and intense cyclonic wind‐storms. Extreme precipitation events are projected by climatic models to become more intense over the continent while droughts might last longer by the end of the century. In dry regions as Southern Europe, soils are predicted to dry out as temperatures and evapotranspiration rise and rain‐bearing atmospheric circulations become less frequent. Prospects on the future of climate indices linked to extreme phenomena are herein derived by using observed and model projected daily meteorological data. Specifically, E‐OBS high resolution gridded datasets of observed precipitation and surface minimum and maximum temperatures have been used as the regional observed baseline. For projections, the same meteorological variables have been obtained from a set of regional climate models integrated in the European EURO‐CORDEX project, considering the RCP8.5 future emissions scenario. A quantile–quantile adjustment has been applied to the simulated regional scenarios to reduce biases in modelled extreme regimes. Results suggest that warm days will substantially increase across Europe, consistently with a decrease of cold nights. An increase in heat wave amplitude is expected across the continent, with South Eastern Europe and the Mediterranean as the most affected regions. In contrast, Northern Europe will undergo the largest decrease in cold spell magnitude. An overall rise in the frequency and volume of heavy precipitations is projected in all seasons, even if the number of dry days is also expected to increase, except in the Baltic countries. Regarding abnormally long dry periods (extreme droughts), we find that the occurrence of episodes would reduce over Europe as consequence of projected increases in length. [ABSTRACT FROM AUTHOR]

Changes in the dynamics of sediment transport in a Mediterranean lake (sediment fluidization events) are linked to atmospheric circulations patterns (trough monthly precipitation). In the basins of Lake Banyoles, located in the northeast of Spain, water enters mainly through subterranean springs, and associated fluctuations in the vertical migration of sediment distribution (fluidization events) present episodic behavior as a result of episodic rainfall in the area. The initiation of the fluidization events takes place when the monthly rainfall is ∼2.7 times greater than the mean monthly rainfall of the rainiest months in the area, especially in spring (April and May), October, and December. The duration of these events is found to be well correlated with the accumulated rainfall of the preceding 10 months before the process initiation. The rainfall, in turn, is mainly associated with six atmospheric circulation patterns among the 19 fundamental circulations that emerged in an earlier study focused on significant rainfall days in Mediterranean Spain. Among them, accentuated surface lows over the northeast of Spain, general northeasterly winds by low pressure centered to the east of Balearic Islands and short baroclinic waves over the Iberian Peninsula, with easterly flows over the northeastern coast of Spain, are found the most relevant atmospheric circulations that drive heavy rainfall events. [ABSTRACT FROM AUTHOR]