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The article aims to quantify a multiyear ocean temperature change at a shallow (5 m) coastal site in the northeastern Adriatic. Measurements were taken between May 2014 and May 2021 with an hourly resolution, allowing for an extraction of temperature variations over longer-term, seasonal, synoptic, quasi-diurnal and hourly timescales. As expected for shallow waters, the seasonal influence is prevalent, while diurnal changes are quasi-persistent throughout the year. Marine heat waves and cold spells are the strongest during spring and summer months. Non-seasonal changes mostly guide longer-term (>10 days) variability, yet rapid temperature changes reach 2 °C/h during stratified seasons. Such rapid changes may impact benthic communities and the physiology of marine species, including bivalves. This is especially important in the era of global warming, in which environmental conditions are already pushed towards their thresholds, and where high-frequency variability analyses can be useful in introducing a precautionary approach for local climate change adaptation. • Multi-year hourly coastal temperature data has been analyzed in the Adriatic. • Near-surface temperature variability across timescales has been documented. • Seasonal variability is prevalent, yet the temperature may change rapidly. • The temperature changes may strongly impact the benthic organisms, like bivalve. [ABSTRACT FROM AUTHOR]

The paper documents dynamics of the middle Adriatic region, and is based on computation of relative geostrophic currents from temperature and salinity data taken along the Palagruža Sill transect between 1957 and 2010. The strongest westward current is found in the central part of the sill, corresponding to the offshore deflected Eastern Adriatic Current (EAC). The Western Adriatic Current (WAC) is, as expected, found in the southern part of the measured transect. The WAC is most significant during the summer season and exhibits stronger variability than the EAC due to the frequent growth of eddies within it. Long-term trends in both the central and southern parts of the sill oppose mean currents, indicating the weakening of the EAC and WAC and therefore of the entire Adriatic thermohaline cell. These opposing trends have not been reproduced by a climate model. [ABSTRACT FROM AUTHOR]

Abstract: The paper attempts to document long-term changes in deep Adriatic water patterns by applying the Self-Organising Maps (SOM) method to temperature, salinity, dissolved-oxygen content, orthophosphate and total inorganic nitrogen profiles sampled at a single deep station in the South Adriatic Pit (SAP) over a half century (1957–2009). Seasonality observed in upper layers has been removed by the least-squares fitting of the annual and semi-annual sinusoidal functions. The sensitivity of the SOM to various parameter combinations reveals the importance of temperature, salinity and dissolved oxygen for mapping different water patterns, while nutrients have less influence on quality and applicability of SOM solutions to the extraction of characteristic SAP water profiles. The quality of fit obtained for different combination of the measured parameters introduced to a SOM suggests that the incomplete combinations of input parameters increase an imperfection in the applicability of SOMs to the dataset. Two modes of long-term changes in the SAP obtained by the SOM analyses are discussed with respect to the processes that drive the variability in the area, e.g., the Adriatic-Ionian Bimodal Oscillation: where the first mode is characterised by rapid changes in the transition of SAP water masses, observed before 1980s (less adoptable by the SOMs), and the second mode is characterised by steady transitions (better adoptable by the SOMs), observed in the 1990s and the 2000s. The SOM method is found to have certain advantages when compared to other methods that have previously been used to distinguish the Adriatic water masses, as it does not depend on predefinition of water mass sources and allows for gaps in series. [Copyright &y& Elsevier]

Abstract: The paper documents numerical modelling exercises designed to reproduce the Proudman resonance on a shelf. Various sinusoidal air pressure disturbances were simulated to travel over the homogeneous waters on a flat or slope bathymetry, qualifying and quantifying the strength of resonance and near-resonance processes in the sea. The results were discussed in light of the worldwide documented destructive meteotsunami events, putting the attention particularly on the effects of the disturbance wavelength, on the weakening of the resonance in near-resonant conditions and on the effect of a slope to the resonance strength. [Copyright &y& Elsevier]

Abstract: The paper documents characteristics of the fundamental Adriatic seiche (period of 21.5h) by analysing hourly sea level data at Split and Rovinj in 1957–2002 interval. The seiche is extracted by digital filter from residual (detided) sea level series. Basic statistics, both on seasonal and interannual scale, as well as flood (threshold-exceeding) analysis has been performed in order to visualise the importance of the seiche. Although mean seiche variance is as small as 2–3%, seiche energy can be much larger than tidal energy during extreme events. The largest seiche amplitudes occur in February and March, being almost two times smaller in summer season. A decrease of seiche flood amplitudes in time has been documented, coinciding with a decrease in the storm surge height. This is presumably due to weakening of atmospheric activity during investigated period. However, a reversal in that trend may result in disastrous and exceptionally high floods in the future, due to coupling with the global sea level rise and its regional (Adriatic) manifestation. [Copyright &y& Elsevier]

In situ thermohaline variables measured monthly or bimonthly in the shallow northern Adriatic at prescribed stations between 1979 and 2017 were correlated with the local (river runoff, precipitation, net heat flux) and remote atmospheric (various hemispheric and regional indices) and oceanic (the Adriatic-Ionian Bimodal Oscillating System, BiOS) drivers acting on monthly to annual timescales. The highest correlation between the temperature and the local drivers was obtained in winter along the western part of the study area, while the rivers and precipitation mostly shaped the summer and December salinity values. The net heat fluxes and river discharges preceding the dense water formation (DWF) by 1–2 months and up to 3 months were found to be important for the February temperature and salinity variability, respectively. No significant correlations were found between the February thermohaline variables and the monthly BiOS index for the phase lags up to −11 months, while the correlation was the largest between the yearly averaged BiOS index and the yearly averaged salinity at phase lags of −2 to −4 years. The bottom yearly averaged salinity has also been highly correlated with the Mediterranean Oscillation index at phase lags of −1 and −3 years, while the yearly averaged surface temperature was influenced by the East Atlantic and East Atlantic/West Russia patterns. Acting independently on different timescales, both the local and remote processes were found to drive the thermohaline variability in the northern Adriatic, thus providing an option for a forecast of the DWF and the thermohaline circulation in the Adriatic-Ionian basin. • Thermohaline observations have been correlated with atmospheric and oceanic drivers. • Local drivers shape the thermohaline variability at monthly timescales. • Remote drivers were correlated with temperature and salinity at yearly timescale. • The BiOS is a key driver for the northern Adriatic decadal thermohaline variability. [ABSTRACT FROM AUTHOR]

This paper aims to document salinity and temperature regimes in the middle and south Adriatic Sea by applying the Self-Organizing Maps (SOM) method to the available long-term temperature and salinity series. The data were collected on a seasonal basis between 1963 and 2011 in two dense water collecting depressions, Jabuka Pit and Southern Adriatic Pit, and over the Palagruža Sill. Seasonality was removed prior to the analyses. Salinity regimes have been found to oscillate rapidly between low-salinity and high-salinity SOM solutions, ascribed to the advection of Western and Eastern Mediterranean waters, respectively. Transient salinity regimes normally lasted less than a season, while temperature transient regimes lasted longer. Salinity regimes prolonged their duration after the major basin-wide event, the Eastern Mediterranean Transient, in the early 1990s. A qualitative relationship between high-salinity regimes and dense water formation and dynamics has been documented. The SOM-based analyses have a large capacity for classifying the oscillating ocean regimes in a basin, which, in the case of the Adriatic Sea, beside climate forcing, is an important driver of biogeochemical changes that impacts trophic relations, appearance and abundance of alien organisms, and fisheries, etc. [ABSTRACT FROM AUTHOR]