Ten years of morphodynamic data at a micro-tidal urban beach: Cala Millor (Western Mediterranean Sea).

Systematic and sustained high quality measurements of nearshore waves and beach morphology are crucial to understand morphodynamic processes that determine beach evolution, to unravel the effects of global warming on sandy coasts and thus improve forecasting models. In 2011 a comprehensive beach monitoring program, the first in the Mediterranean Sea, started at Cala Millor Beach on the island of Mallorca (Spain). The aim was to provide long-term datasets of near-shore morphodynamics in a carbonate sandy micro-tidal and semi-embayed beach fronted by a Posidonia oceanica seagrass meadow.

Spatial and temporal variation of methane emissions in the coastal Balearic Sea, Western Mediterranean.

Methane (CH) gas is the most important GHG after carbon dioxide, with open ocean areas acting as discreet CH sources and coastal regions as intense but variable CH sources to the atmosphere. Here, we report CH concentrations and air-sea fluxes in the coastal area of the Balearic Islands Archipelago (Western Mediterranean Basin). CH levels and related biogeochemical variables were measured in three coastal sampling sites between 2018 and 2021, with two located close to the densely populated island of Mallorca and one in a pristine area in the Cabrera Archipelago National Park.

pH trends and seasonal cycle in the coastal Balearic Sea reconstructed through machine learning.

The decreasing seawater pH trend associated with increasing atmospheric carbon dioxide levels is an issue of concern due to possible negative consequences for marine organisms, especially calcifiers. Globally, coastal areas represent important transitional land-ocean zones with complex interactions between biological, physical and chemical processes. Here, we evaluated the pH variability at two sites in the coastal area of the Balearic Sea (Western Mediterranean).

Tracking the global reduction of marine traffic during the COVID-19 pandemic.

The COVID-19 pandemic has resulted in unparalleled global impacts on human mobility. In the ocean, ship-based activities are thought to have been impacted due to severe restrictions on human movements and changes in consumption. Here, we quantify and map global change in marine traffic during the first half of 2020.

Nearshore spatio-temporal sea surface trawls of plastic debris in the Balearic Islands.

Nearshore sea-surface manta trawls were carried out monthly at seven sites along the coastline of Mallorca in the Balearic Islands in the Western Mediterranean Sea. Plastic marine debris was present in all trawls (n = 63) with an overall average abundance of 858,029 ± 4,082,964 items/km (mean ± standard deviation) and weight of 4,520 ± 22,806 g(DW)/km and the micro-plastic fraction (74%) dominating the size class. Polyethylene (LDPE and HDPE) was the most common polymer (70%) with high spatial heterogeneity, especially along the north-western coast.

Towards the integration of animal-borne instruments into global ocean observing systems.

Marine animals are increasingly instrumented with environmental sensors that provide large volumes of oceanographic data. Here, we conduct an innovative and comprehensive global analysis to determine the potential contribution of animal-borne instruments (ABI) into ocean observing systems (OOSs) and provide a foundation to establish future integrated ocean monitoring programmes. We analyse the current gaps of the long-term Argo observing system (>1.

Quarterly variability of floating plastic debris in the marine protected area of the Menorca Channel (Spain).

Plastic pollution is widespread in all the oceans and seas, representing a significant threat to most of their ecosystems even in marine protected areas (MPAs). This study determines the floating plastic distribution in four different periods between 2014 and 2015 in the recently approved Menorca Channel MPA (Balearic Islands). Plastic debris were persistent during all sampling periods on the surface of the Channel, composed mainly by the microplastic sizes.

Ageostrophic Frontal Processes Controlling Phytoplankton Production in the Catalano-Balearic Sea (Western Mediterranean).

Buoyancy-induced unstable boundary currents and the accompanying retrograde density fronts are often the sites of pronounced mesoscale activity, ageostrophic frontal processes, and associated high biological production in marginal seas. Biophysical model simulations of the Catalano-Balearic Sea (Western Mediterranean) illustrated that the unstable and nonlinear southward frontal boundary current along the Spanish coast resulted in a strain-driven frontogenesis mechanism. High upwelling velocities of up to 80 m d(-1) injected nutrients into the photic layer and promoted enhanced production on the less dense, onshore side of the front characterized by negative relative vorticity.

Fueling plankton production by a meandering frontal jet: a case study for the Alboran Sea (Western Mediterranean).

A three dimensional biophysical model was employed to illustrate the biological impacts of a meandering frontal jet, in terms of efficiency and persistency of the autotrophic frontal production, in marginal and semi-enclosed seas. We used the Alboran Sea of the Western Mediterranean as a case study. Here, a frontal jet with a width of 15-20 km, characterized by the relatively low density Atlantic water mass, flows eastward within the upper 100 m as a marked meandering current around the western and the eastern anticyclonic gyres prior to its attachment to the North African shelf/slope topography of the Algerian basin.

Spatial scale, means and gradients of hydrographic variables define pelagic seascapes of bluefin and bullet tuna spawning distribution.

Seascape ecology is an emerging discipline focused on understanding how features of the marine habitat influence the spatial distribution of marine species. However, there is still a gap in the development of concepts and techniques for its application in the marine pelagic realm, where there are no clear boundaries delimitating habitats. Here we demonstrate that pelagic seascape metrics defined as a combination of hydrographic variables and their spatial gradients calculated at an appropriate spatial scale, improve our ability to model pelagic fish distribution.