Alfredo Izquierdo

Universidad de Cádiz | UCA · Department of Applied Physics

Coastal altimetry products are available and are being extensively validated. Their accuracy has been assessed in many coastal zones around the world and they are ready for exploitation near the shore. This opens a variety of applications of the sea level data obtained from the specific reprocessing of radar altimeter signals in the coastal strip....

The impact of tides on the spreading of the Mediterranean Outflow Waters (MOW) in the Gulf of Cadiz is investigated through a series of targeted numerical experiments using an ocean general circulation model. The full ephimeridic luni-solar tidal potential is included as forcing. The model grid is global with a strong zoom around the Iberian Penins...

The modification of waves by shipwrecks and the resulting scour play important roles in shipwreck site formation , and conservation of archaeological sites. The oscillatory flow induced by waves and its interaction with the hull structure at a historic shipwreck site was analyzed using a two phase 2D model based on the Reynolds averaged Navier-Stok...

The key role of the South Atlantic Anticyclone (SAA) on the seasonal cycle of the tropical Atlantic is investigated with a regionally coupled atmosphere–ocean model for two different coupled domains. Both domains include the equatorial Atlantic and a large portion of the northern tropical Atlantic, but one extends southward, and the other northwest...

The general circulation models used to simulate global climate typically feature resolution too coarse to reproduce many smaller scale processes, which are crucial to determining the regional responses to climate change. A novel approach to downscale climate change scenarios is presented which includes the interactions between the North Atlantic Oc...

The Mauritania-Senegalese upwelling region (MSUR), the southernmost region of the Canary current upwelling system, is well-known for its coastal productivity and the key role it plays in enriching the oligotrophic open ocean through the offshore transport of the upwelled coastal waters. The great ecological and socio-economic importance makes it ne...

In this work, we retracked altimeter waveforms of ESA satellites. ERS2 RA and Envisat RA2 from descending track 0360 over the eastern side of the Strait of Gibraltar using the Adaptive Leading Edge Subwaveform ALES retracker.

Dense water formation in the eastern Mediterranean (EMed) is essential in sustaining the Mediterranean overturning circulation. Changes in the sources of dense water in the EMed point to changes in the circulation and water properties of the Mediterranean Sea. Here we examine with a regional climate system model the changes in the dense water forma...

Internal waves are commonly observed in oceans and lakes where high stratification exists. In the present study in the Strait of Gibraltar, we analyse internal soliton signals recorded in different locations in their eastward propagation from their release point (Camarinal Sill) to the continental slope of the northwestern Alboran Sea. Moreover, th...

The Antarctic Intermediate Water (AAIW), one of the most important global intermediate water masses, spreads over the world ocean. Its propagation limit at the Northeast Subtropical Atlantic is characterized by its encounter with the Mediterranean Water (MW), which presents dissimilar thermohaline properties. Previous studies of the AAIW in this re...

Dense water formation in the Eastern Mediterranean (EMed) is essential in sustaining the Mediterranean 10 overturning circulation. Changes in the sources of dense water in the EMed point to changes in the circulation and the water properties of the Mediterranean Sea. Here we examine with a regional climate system model the changes in the dense wate...

Coastal areas are characterized by high energetic conditions associated to the wave transformation process and by numerous underwater cultural heritage (UCH) sites whose preservation is crucial given their cultural and economic value. UCH management requires a decision support system to prioritize UCH interventions and actions for long-term preserv...

This work presents the quality performance and the capabilities of altimetry derived wind speed (WS) retrievals from the altimeters on-board Copernicus satellites Sentinel-3A/B (S3A/B) for the spatial assessment of WS outputs from the weather research and forecasting (WRF) model over the complex area of the Gulf of Cádiz (GoC), Spain. In order to a...

Deep water formation (DWF) in the North Western Mediterranean (NWMed) is a key feature of Mediterranean overturning circulation. DWF changes under global warming may have an impact on the Mediterranean biogeochemistry and marine ecosystem. Here we analyze the deep convection in the Gulf of Lions (GoL) in a changing climate using a regional climate...

The Tyrrhenian Sea plays an important role in the winter deep water formation in the northwestern Mediterranean through the water that enters the Ligurian Sea via the Corsica Channel. Therefore, the study of the impact of the changes on the future climate on the Tyrrhenian circulation and its consequences represents an important issue. Furthermore,...

The Canary current upwelling is one of the major eastern boundary coastal upwelling systems in the world, bearing a high productive ecosystem and commercially important fisheries. The Canary current upwelling system (CCUS) has a large latitudinal extension, usually divided into upwelling zones with different characteristics. Eddies, filaments and o...

Deep water formation (DWF) in the North Western Mediterranean (NWMed) is a key feature of Mediterranean overturning circulation. Changes in DWF under global warming may have an impact on the regional and even on the global climate. Here we analyze the deep convection in the Gulf of Lions (GoL) in a changing climate using an atmosphere-ocean regiona...

A catchment model for river basins and a hydrodynamic model were combined in order to simulate the spreading of the turbidity plume produced by sediment discharges from the Guadalquivir River basin within the Gulf of Cádiz under different meteorological conditions. The current fields provided by the hydrodynamic model and a transport-diffusion sche...

The Tyrrhenian Sea plays an important role in the winter deep water formation in the North Western Mediterranean through the water that enters the Ligurian Sea via the Corsica Channel. Therefore, the study of the impact of the changes in the future climate on the Tyrrhenian circulation and its consequences represents an important issue. Furthermore...

The Canary current upwelling is one of the major eastern boundary coastal upwelling systems in the world, bearing a high productive ecosystem and commercially important fisheries. The Canary current upwelling system (CCUS) has a large latitudinal extension, usually divided into upwelling zones with different characteristics. Eddies, filaments and o...

Purpose-The main goal of the present investigation is to estimate the level of tourists' environmental consciousness (EC), which forms their intention to behave environmentally friendly (EF) during vacation time. Design-Variables of environmental awareness, environmental perception, environmental attitude, and perceived behavioural control were emp...

Climate simulations for the North Atlantic and Europe for recent and future conditions simulated with the regionally coupled ROM model are analyzed and compared to the results from the MPI‐ESM. The ROM simulations also include a biogeochemistry and ocean tides. For recent climate conditions, ROM generally improves the simulations compared to the dr...

Spain is one of the four world leaders in coastal tourism. To keep the top position in such a highly competitive market, coastal managers in Spain need to constantly monitor the social, ecological, and economic components of ‘sun and sea’ tourism. Thus, the main goals of the present study are to analyse the most visited Spanish coastal destinations...

We analyze the climate change signal in the Mediterranean Sea using the regionally coupled model REMO–OASIS–MPIOM (ROM; abbreviated from the regional atmosphere model, the OASIS3 coupler and the Max Planck Institute Ocean Model). The ROM oceanic component is global with regionally high horizontal resolution in the Mediterranean Sea so that the wate...

The Caribbean Sea provides significant ecosystem services to the livelihood and well-being of countries in the region. Protection of the marine ecosystem requires policy on coastal water quality that considers ecologically-relevant thresholds and has a scientific foundation linking land-based discharges with seawater quality. This study demonstrate...

Coastal food services are an important segment within 'sea and sun' tourism. They have a direct impact on the environment from liquid and solid waste generation, air contamination, and excessive energy and water consumption. Mass tourism and the contemporary threat of climate change enhance the anthropogenic intrusion, especially in vulnerable coas...

The main features of the surface currents in the Strait of Gibraltar and Algeciras Bay are analyzed from the numerical results of three-dimensional hydrodynamic modeling, complemented and validated through observational data. The relative contributions of the main processes affecting the surface current patterns (i.e. mean background flows, barotro...

Coastal upwelling systems are very important from the socio-economic point of view due to their high productivity, but they are also vulnerable under changing climate. The impact of climate change on the Canary Current Upwelling System (CCUS) has been studied in recent years by different authors. However, these studies show contradictory results on...

The ecosystem function of local fisheries holds great societal importance in the coastal zone of Cartagena, Colombia, where coastal communities depend on artisanal fishing for their livelihood and health. These fishing resources have declined sharply in recent decades partly due to issues of coastal water pollution. Mitigation strategies to reduce...

Drifting Fish Aggregating Devices (dFADs) are small drifting platforms with an attached solar powered buoy that report their position with daily frequency via GPS. We use data of 9,440 drifting objects provided by a buoys manufacturing company, to test the predictions of surface current velocity provided by two of the main models: the NEMO model us...

We assess the role of ocean feedbacks in the simulation of the present climate and on the downscaled climate change signal in the Mediterranean Sea with the regionally coupled model REMO-OASIS-MPIOM (ROM). The ROM oceanic component is global with regionally high horizontal resolution in the Mediterranean Sea. In our setup the Atlantic and Black Sea...

A 3-D nonlinear, finite-difference, high-resolution, hydrodynamic model, extended with a direct implementation of the non-hydrostatic pressure, is applied to study the influence of the non-hydrostatic contribution to the generation and propagation of short-period wave fronts (less than 1 h) in the domain of the Gibraltar Strait. The generation, rup...

A bay's capacity to buffer fluvial fluxes between the land and sea is sensitive to hydrological changes that can affect its water renewal rates. In Cartagena Bay, Colombia, pollution issues have been associated with freshwater fluxes which are projected to increase in future years. This has led to plans to reduce freshwater flows by constructing up...

Accurate coastal altimetry data are important for coastal observing systems (monitoring) and to re-analyze previous datasets. In this work, we analyzed the cross-strait variability in the eastern side of the Strait of Gibraltar using one descending track from the European Space Agency (ESA) Envisat RA-2 descending track #0360. We developed an accur...

Metocean modeling resources from an operational oceanography system are applied to assess the hazard of bacterial contamination, resulting from domestic/industrial wastewater discharged into potential bivalve mollusk harvesting areas in Cadiz Bay (Andalusia). The proposed methodology is aimed to at meeting the European Union regulations and best pr...

A shipwreck site located off Sancti Petri sand spit (Cadiz, Spain) was identified as a Temeraire-class 74-gun French ship. The archaeological deposits relate it to the Fougueux, sunken after the Battle of Trafalgar. The site contains some pieces of the naval structure, 32 iron guns, and a large anchor, but two thirds of the ship is missing. Availab...

An understanding of the interactions between biological, chemical and physical dynamics is especially important for the adequate conservation of the Underwater Cultural Heritage. However, while physical and chemical processes are relatively well-investigated, the biological communities associated with these habitats are poorly studied. We compared...

The effect of subinertial sea level atmospheric pressure fluctuations on the inflow intensity of the surface Atlantic waters through the Strait of Gibraltar and its impacts on the dynamics of the Alboran Sea is studied. The results confirm that the exchange flows in the Strait is affected by atmospheric processes of much larger spatial scale than t...

Shoreline evolution studies are mostly performed by comparison of vertical images (e.g. aerial photographs and satellite imagery), being limited to the last decades. However, phenomena such as longer term climatic fluctuations may cause important secular coastal changes which are mostly unknown. The use of archaeological remains as shoreline proxie...

The identification and prioritization of pollution sources is essential to coastal zone management. This task is complicated when a variety of pollution sources are found and by limited data availability, which can result in an inconclusive assessment and differing public perceptions, ultimately hindering the progress of management actions. This is...

Cartagena Bay, one of the Caribbean's hot spots of pollution, is an estuarine system connected to the Caribbean Sea by two straits. Large freshwater discharges from the Dique Canal into the south of the bay produce estuarine conditions strongly related to the seasonal variability of runoff from the Magdalena River watershed. The bay's seasonal cond...

Two wrecks related to the Battle of Trafalgar (1805) were studied. Followingthe guidelines of the UNESCO-2001 Convention for the Protection of the Underwater Cultural Heritage, a holistic and interdisciplinary approach based on the development of four of the thirty-six Rules of this international agreement was applied. A non-destructive survey tech...

We present a study of the potential impact of climate change on the temperature, precipitation and on some extreme weather events in the Caucasus region according to the 4.5 and 8.5 RCP scenarios. We apply a dynamic downscaling technique with a high-resolution regional model forced by the Max Planck Institute Earth System Model (MPI-ESM). In contra...

We make a review on the modelling efforts devoted to better understand the complex oceanography of the Strait of Gibraltar, where Atlantic waters enter the Mediterranean Sea as a surface flow, and Mediterranean outflowing waters spread into the interior of the North Atlantic forming a prominent basin-scale termohaline anomaly at mid-depths. Besides...

The evolution of the shallow water wave-dominated Fougueux wreck site in the Gulf of Cadiz was investigated through repeat bathymetric surveys, wave- and current-velocity field measurements, and numerical modeling. This multidisciplinary approach was used to understand the relationships between scouring, morphodynamic change, and hydrodynamic forci...

Contour map elaborated by Alfredo Izquierdo of sea level pressure, vectors of wind velocity field, and significant wave height on December 2009 storm from the ERA-interim reanalysis dataset . In the article, Figure 3b represents this conditions on 24 December 2009. In: T. Fernández-Montblanc, A. Izquierdo, M. Bethencourt, Scattered shipwreck site...

Simulation elaborated over an antique nautical chart by Tomas Fernandez Montblanc (version 1): In order to establish the dispersion area of the Fougueux’s scattered remains, a Lagrangian dispersion model (LDM) was employed. In: T. Fernández-Montblanc, A. Izquierdo, M. Bethencourt, Scattered shipwreck site prospection: the combined use of numerical...

Simulation elaborated in false 3D by Tomas Fernandez Montblanc (version 2): In order to establish the dispersion area of the Fougueux’s scattered remains, a Lagrangian dispersion model (LDM) was employed. In: T. Fernández-Montblanc, A. Izquierdo, M. Bethencourt, Scattered shipwreck site prospection: the combined use of numerical modeling and docume...

The general circulation models used to simulate global climate typically feature resolution too coarse to reproduce many smaller-scale processes, which are crucial to determining the regional responses to climate change. A novel approach to downscale climate change scenarios is presented which includes the interactions between the North Atlantic Oc...

Underwater cultural heritage (UCH) risk assessment due to mean and extreme storms was conducted at Bucentaure and Fougueux shipwreck sites. Storms representative of mean and extreme conditions were simulated using numerical modeling tools. Temporal series of sea level, waves, fraction breaking and maximum bed shear stress were obtained at the studi...

The deterioration of shipwrecks varies depending on location and time due to changes in environmental conditions, and the nature of the archaeological objects. In order to assess the influence of physical, chemical and biological conditions in the damage and protection of underwater historical heritage, these variables were monitored in two shipwre...

A shipwreck site located in Camposoto beach (Cadiz, Spain) was identified as Fougueux, a French ship (Battle of Trafalgar, 1805). The site contains hull remains, 32 iron guns and a large anchor, but two-thirds of the ship are missing. Available information (including ships’ logbooks of weather observations and other historic documents) establishes...

In the present work, the relationship between Underwater Cultural Heritage (UCH) deterioration and marine environmental factors assessed in Fougueux and Bucentaure site are presented. The two war ships were sunken during the Trafalgar Battle (1805) in the Bay of Cadiz. An assessment of UCH deterioration was carried out. Firstly, an archaeomet- ric...

The M2 tidal circulation in Algeciras Bay (Strait of Gibraltar) is analyzed using a 3-D, nonlinear, baroclinic, hydrodynamic model, in conjunction with observed data series. Results show the influence of the density stratification on the vertical structure of the M2 currents in Algeciras Bay, although its tidal dynamics shows major differences with...

A three-dimensional, nonlinear, high-resolution, sigma coordinate, hydrodynamic model was applied to study the sea surface manifestation of short-period internal waves measured in Algeciras Bay and the Strait of Gibraltar. Model results reproduce the tidally induced generation of the internal bore over the Camarinal Sill and its disintegration into...

A shipwreck site located in Camposoto beach (Cadiz, Spain) and containing 31 iron guns and a large anchor was protected and included in the General Catalogue of the Andalusian Historical Heritage in 2008. The archaeological remains relate it to the Battle of Trafalgar identifying it with the “Fougueux”, a Téméraire class 74 gun French ship of the l...

The special hydrodynamic regime of the Andalusian Coast, the important meteorological influence, and the intense maritime traffic of oil tankers make the use of field measurements and appropriate hydrodynamic models to be an essential part of an operational system for the prevention and management of oil spills in these waters. An operational ocean...