The Origin of Sand and Its Colour on the South-Eastern Coast of Spain: Implications for Erosion Management

Sand colour can give important information about mineral composition and, consequently, sediment source areas and input systems. Beach appearance, which is mostly linked to sand colour, has a relevant economic function in tourist areas. In this paper, the colour of 66 sand samples, collected along both natural and nourished beaches in the western Mediterranean coast of Spain, were assessed in CIEL*a*b* 1976 colour space. The obtained results showed relevant differences between natural and artificially nourished beaches. The colour of many nourished beaches generally differs from the native one because the origin of the injected sand is different. The native sand colour coordinates’ range is: L* (40.16–63.71); a* (−1.47–6.40); b* (7.48–18.06). On the contrary, for nourished beaches’ the colour range is: L* (47.66–70.75); a*(0.72‒5.16); b* (5.82–18.82). Impacts of beach nourishment on the native sand colour were studied at San Juan beach, the most popular one along the study area. Nourishment works were performed after severe erosion, usually linked to anthropic activities/structures and storm events, but also to increase beach width and hence benefit tourism.

Download Full-text

Extreme sea events during the last millennium in the northeast of Morocco

Natural Hazards and Earth System Science ◽

10.5194/nhess-15-203-2015 ◽

2015 ◽

Vol 15 (2) ◽

pp. 203-211 ◽

Cited By ~ 23

Author(s):

O. Raji ◽

L. Dezileau ◽

U. Von Grafenstein ◽

S. Niazi ◽

M. Snoussi ◽

...

Keyword(s):

High Frequency ◽

Western Mediterranean ◽

Mediterranean Coast ◽

Extreme Weather Events ◽

Geochemical Data ◽

Last Millennium ◽

Storm Events ◽

Recent Event ◽

Weather Events ◽

Event Record

Abstract. The Moroccan Mediterranean coast is located in one of the area's most vulnerable to extreme weather events or tsunami hazards. The objective of this research is to reconstruct the historical extreme submersion-event record using sea-induced deposits preserved in coastal lagoon. The Nador lagoon is the largest Moroccan lagoon (115 km2). It is located along the western Mediterranean, which has a high cyclogenetic character and is exposed to tsunamis from the Alboran Sea. The sandy barrier which separates the lagoon from the Mediterranean Sea is marked by much overwash, which indicate how intensely it has been exposed to the adverse sea events through history. Using the UWITEC© gravity coring platform, an undisturbed MC4.5 core (1.15 m long) was successfully sampled in the studied lagoon. To identify extreme sea events, a multi-proxy approach was applied combining sedimentological and geochemical data. Three paleoevents were identified; all of them are concentrated over the last 500 years, and the most recent event corresponds to the 1889 storm. For the others deposits, it is difficult to determine exactly their origin; however, the high frequency of storm events over the relevant period and the absence of historical tsunamis evidence is more in favor of the meteorological origin.

Download Full-text

Tsunami hazard at the Western Mediterranean Spanish coast from seismic sources

Natural Hazards and Earth System Science ◽

10.5194/nhess-11-227-2011 ◽

2011 ◽

Vol 11 (1) ◽

pp. 227-240 ◽

Cited By ~ 15

Author(s):

J. A. Álvarez-Gómez ◽

ĺ. Aniel-Quiroga ◽

M. González ◽

L. Otero

Keyword(s):

Iberian Peninsula ◽

Western Mediterranean ◽

Mediterranean Coast ◽

Balearic Islands ◽

Mitigation Measures ◽

Eastern Coast ◽

The North ◽

Spanish Coast ◽

Tsunami Risk ◽

The Mediterranean

Abstract. Spain represents an important part of the tourism sector in the Western Mediterranean, which has been affected in the past by tsunamis. Although the tsunami risk at the Spanish coasts is not the highest of the Mediterranean, the necessity of tsunami risk mitigation measures should not be neglected. In the Mediterranean area, Spain is exposed to two different tectonic environments with contrasting characteristics. On one hand, the Alboran Basin characterised by transcurrent and transpressive tectonics and, on the other hand, the North Algerian fold and thrust belt, characterised by compressive tectonics. A set of 22 seismic tsunamigenic sources has been used to estimate the tsunami threat over the Spanish Mediterranean coast of the Iberian peninsula and the Balearic Islands. Maximum wave elevation maps and tsunami travel times have been computed by means of numerical modelling and we have obtained estimations of threat levels for each source over the Spanish coast. The sources on the Western edge of North Algeria are the most dangerous, due to their threat to the South-Eastern coast of the Iberian Peninsula and to the Western Balearic Islands. In general, the Northern Algerian sources pose a greater risk to the Spanish coast than the Alboran Sea sources, which only threaten the peninsular coast. In the Iberian Peninsula, the Spanish provinces of Almeria and Murcia are the most exposed, while all the Balearic Islands can be affected by the North Algerian sources with probable severe damage, specially the islands of Ibiza and Minorca. The results obtained in this work are useful to plan future regional and local warning systems, as well as to set the priority areas to conduct research on detailed tsunami risk.

Download Full-text

Storm Energy Flux Characterization along the Mediterranean Coast of Andalusia (Spain)

Water ◽

10.3390/w11030509 ◽

2019 ◽

Vol 11 (3) ◽

pp. 509 ◽

Cited By ~ 11

Author(s):

Rosa Molina ◽

Giorgio Manno ◽

Carlo Lo Re ◽

Giorgio Anfuso ◽

Giuseppe Ciraolo

Keyword(s):

Energy Flux ◽

Wave Climate ◽

Mediterranean Coast ◽

Storm Events ◽

Cumulative Energy ◽

Weather Forecasts ◽

Wave Energy Flux ◽

The Mediterranean ◽

Definition Of ◽

Storm Characteristics

This paper investigates wave climate and storm characteristics along the Mediterranean coast of Andalusia, for the period 1979–2014, by means of the analysis of wave data on four prediction points obtained from the European Centre for Medium-Range Weather Forecasts (ECMWF). Normally, to characterize storms, researchers use the so-called “power index”. In this paper, a different approach was adopted based on the assessment of the wave energy flux of each storm, using a robust definition of sea storm. During the investigated period, a total of 2961 storm events were recorded. They were classified by means of their associated energy flux into five classes, from low- (Class I) to high-energetic (Class V). Each point showed a different behavior in terms of energy, number, and duration of storms. Nine stormy years, i.e., years with a high cumulative energy, were recorded in 1980, 1983, 1990, 1992, 1995, 2001, 2008, 2010, and 2013.

Download Full-text

Bayesian trend analysis of extreme wind using observed and hindcast series off the Catalan coast, NW Mediterranean Sea

Natural Hazards and Earth System Science ◽

10.5194/nhess-14-2387-2014 ◽

2014 ◽

Vol 14 (9) ◽

pp. 2387-2397 ◽

Cited By ~ 3

Author(s):

M. I. Ortego ◽

J. J. Egozcue ◽

R. Tolosana-Delgado

Keyword(s):

Generalized Pareto Distribution ◽

Western Mediterranean ◽

Quality Data ◽

Occurrence Rate ◽

Data Series ◽

Model Parameters ◽

Storm Events ◽

Average Wind Speed ◽

Magnitude Distribution ◽

Catalan Coast

Abstract. It has been suggested that climate change might modify the occurrence rate and magnitude of large ocean-wave and wind storms. The hypothesised reason is the increase of available energy in the atmosphere–ocean system. Forecasting models are commonly used to assess these effects, given that good-quality data series are often too short. However, forecasting systems are often tuned to reproduce the average behaviour, and there are concerns on their relevance for extremal regimes. We present a methodology of simultaneous analysis of observed and hindcast data with the aim of extracting potential time drifts as well as systematic regime discrepancies between the two data sources. The method is based on the peak-over-threshold (POT) approach and the generalized Pareto distribution (GPD) within a Bayesian estimation framework. In this context, storm events are considered points in time, and modelled as a Poisson process. Storm magnitude over a reference threshold is modelled with a GPD, a flexible model that captures the tail behaviour of the magnitude distribution. All model parameters, i.e. shape and location of the magnitude GPD and the Poisson occurrence rate, are affected by a trend in time. Moreover, a systematic difference between parameters of hindcast and observed series is considered. Finally, the posterior joint distribution of all these trend parameters is studied using a conventional Gibbs sampler. This method is applied to compare hindcast and observed series of average wind speed at a deep buoy location off the Catalan coast (NE Spain, western Mediterranean; buoy data from 2001; REMO wind hindcasting from 1958 on). Appropriate scale and domain of attraction are discussed, and the reliability of trends in time is addressed.

Download Full-text

Scientific collaboration for early detection of invaders results in a significant update on estimated range: lessons from Stenothoe georgiana Bynum & Fox 1977

Mediterranean Marine Science ◽

10.12681/mms.22583 ◽

2020 ◽

Author(s):

GEMMA MARTÍNEZ-LAIZ ◽

MACARENA ROS ◽

JOSÉ MANUEL GUERRA-GARCÍA ◽

AGNESE MARCHINI ◽

VICTORIA FERNÁNDEZ-GONZÁLEZ ◽

...

Keyword(s):

Early Detection ◽

First Record ◽

Western Mediterranean ◽

Mediterranean Coast ◽

Amphipod Species ◽

Indigenous Species ◽

Scientific Cooperation ◽

Vectors Of Introduction ◽

Non Indigenous Species ◽

Effective Spread

Detection of new non-indigenous species is often delayed when taxonomically challenging taxa are involved, such as small-sized marine organisms. The present study highlights the relevance of scientific cooperation in the early detection of the invader amphipod Stenothoe georgiana. Originally described from North Carolina (USA), the species was recently found in Chile and the Western Mediterranean. Here, we provide the first record of the species in Macaronesia, Atlantic coasts of continental Europe, North Africa and Australia, and extend its known distribution along the Mediterranean coast. Just like other small crustaceans, shipping (including recreational boating) and aquaculture are probably the main vectors of introduction and secondary spread for this amphipod species. This case of S. georgiana sheds light on the importance of promoting taxonomical knowledge, and building multidisciplinary expertise networks that ensure an effective spread of alien species information. We also encourage the implementation of standardized monitoring methodologies to facilitate early detection of small mobile invaders.

Download Full-text

Diet of Yellow-legged Gull (Larus michahellis) chicks along the Spanish Western Mediterranean coast: the relevance of refuse dumps

Journal of Ornithology ◽

10.1007/s10336-008-0346-2 ◽

2008 ◽

Vol 150 (1) ◽

pp. 265-272 ◽

Cited By ~ 76

Author(s):

Raül Ramos ◽

Francisco Ramírez ◽

Carolina Sanpera ◽

Lluís Jover ◽

Xavier Ruiz

Keyword(s):

Western Mediterranean ◽

Mediterranean Coast ◽

Larus Michahellis ◽

Refuse Dumps

Download Full-text

First record of the Levantine species Scoloplos haasi (Orbiniidae: Scolecida: Annelida) from the Mediterranean coast of Spain

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315409991305 ◽

2009 ◽

Vol 90 (5) ◽

pp. 1051-1054 ◽

Cited By ~ 1

Author(s):

Eduardo López

Keyword(s):

Natural History ◽

Iberian Peninsula ◽

British Museum ◽

First Record ◽

Western Mediterranean ◽

Mediterranean Coast ◽

Geographical Range ◽

Polychaete Species ◽

The Mediterranean

During an investigation devoted to characterize all the Orbiniidae polychaete species present in the Iberian Peninsula, several individuals previously identified as Scoloplos armiger showed to actually belong to Scoloplos haasi, a species to date considered endemic from Israel. The comparison with the holotype deposited in the British Museum of Natural History confirmed the identification. This record of S. haasi is not only a new one for the western Mediterranean but also the first one out of its original locality, extending largely westwards the geographical range of the species.

Download Full-text