Erosion consequences on beach functions along the Maresme coast (NW Mediterranean, Spain)

A methodology to analyse the influence of erosion on beach functions at a regional scale is presented. The method considers erosion hazards at different timescales and assesses consequences by evaluating impacts on recreation and protection functions. To provide useful information to decision makers for managing these functions, hazard and consequences are integrated at the municipal level within a risk matrix. This methodology is applied at the Maresme, a 45-km sandy coast situated northward of Barcelona, which supports a strong urban and infrastructure development as well as an intensive beach recreational use. Obtained results indicate differentiated erosion implications along the region, depending on the management target considered. Thus, southern municipalities are more prone to erosion affecting the protection function of the beach and leisure use by the local population, whereas erosion will have a greater effect on foreign tourism in the northern municipalities. These results highlight the necessity to employ an articulated erosion risk assessment focusing on specific targets depending on the site in question. This methodology can help coastal managers to adopt tailored measures to manage erosion impacts towards specific goals, in a more efficient and sustainable manner

Impact of sea-level rise on the tourist-carrying capacity of Catalan beaches

Tourism provides about 11% of Catalonia's GDP, with most accommodations placed being associated with the “sun-and-sand” model. Since beaches are the main resource to be exploited, it is important to assess how their future evolution can affect this economic sector. Accordingly, we present a methodology to assess the effect of shoreline evolution on beach recreational carrying capacity (BCC) at different territorial scales considering different climate change scenarios. Our results suggest that by 2050, in the absence of climate change, tourist BCC will decrease down to 83% of current values due to the dominant erosive behaviour of the Catalan coast. When sea-level rise is considered, BCC will decrease further, with expected values ranging from 74% to 53% of current capacity for the tested scenarios (RCP4.5 and High-end respectively). Hence, current erosional trends are adverse for future development of coastal tourism in Catalonia, and accelerated sea-level rise exacerbates this adverse situation. The adopted methodology permits to locate hotspots along the territory where local BCC values collapse as well as to predict when this will occur under a given climatic scenario. Moreover, the use of different spatial scales to integrate BCC permits to test management strategies to sustaining the recreational use of beaches.</p

Storm-induced damages along the Catalan coast (NW Mediterranean) during the period 1958–2008

11 pages, 12 figures, 4 tablesThe temporal and spatial patterns of storm-induced damage along the Catalan coast (NW Mediterranean) during the last 50 years have been analyzed to identify main climatic and non-climatic forcings. In the absence of systematic data, a storm-induced damage database compiled from press news has been built, which together with an intensity scale has allowed us to characterize the frequency and intensity of damage. Although no temporal trend has been detected in storm-induced hazards, coastal damage has increased at a rate of about 40% per decade during the last 50 years along the Catalan coast. The main non-climatic factors identified controlling this trend were the urban growth along the coastal fringe and the generalized erosive behavior of beaches. The first one increased values at risk and the second one increased their exposure to storm-induced hazards. In spite of the importance of non-climatic factors to modulate coastal damage, an exponential dependence of damages on storm-induced inundation and erosion was detected. In addition to this, storm-induced geomorphic changes along the Ebro delta coast have also been analyzed. During the period analyzed, “harmful” storms seem to be clustered, with most of the events being present in the late 1990s and especially from 2001 to 2004, resulting in frequent events of intense beach/barrier breaching, massive overwash and flooding. They are mainly expressed in sensitive areas which are subject to long-term erosional processes and comprise a low-lying profile and a narrow beach. This reflects the role of coastal morphology in controlling the intensity of storm-induced hazards along the deltaic coast. Shoreline evolution rates calculated during this period were significantly larger than the previously recorded ones, reflecting a pulsating erosion behavior where large pulses occur during stormy periods and are reduced during post-storm periods. Under the present scenario of maximum coastal development, storm-induced damage has been reported almost every year which could indicate that the present overall beach configuration status along the Catalan coast has reached its limit for protecting the hinterland against stormsThis work has been done in the framework of the VuCoMA research project funded by the Spanish Ministry of Science and Innovation (CTM2008-05597/MAR). We thank the Department of Territorial Policy and Public Works of the Autonomous Government of Catalonia and to Puertos del Estado (Spanish Ministry of Public Works) for supplying wave data used in this study. This work could not been done without the effort and generosity of La Vanguardia in digitizing and making available their archives to the public. The second and third authors were supported by PhD grants from the CSIC and the Spanish Ministry of Education respectivelyPeer reviewe

Storm-induced damages along the Catalan coast (NW Mediterranean) during the period 1958-2008

11 pages, 12 figures, 4 tablesThe temporal and spatial patterns of storm-induced damage along the Catalan coast (NW Mediterranean) during the last 50 years have been analyzed to identify main climatic and non-climatic forcings. In the absence of systematic data, a storm-induced damage database compiled from press news has been built, which together with an intensity scale has allowed us to characterize the frequency and intensity of damage. Although no temporal trend has been detected in storm-induced hazards, coastal damage has increased at a rate of about 40% per decade during the last 50 years along the Catalan coast. The main non-climatic factors identified controlling this trend were the urban growth along the coastal fringe and the generalized erosive behavior of beaches. The first one increased values at risk and the second one increased their exposure to storm-induced hazards. In spite of the importance of non-climatic factors to modulate coastal damage, an exponential dependence of damages on storm-induced inundation and erosion was detected. In addition to this, storm-induced geomorphic changes along the Ebro delta coast have also been analyzed. During the period analyzed, “harmful” storms seem to be clustered, with most of the events being present in the late 1990s and especially from 2001 to 2004, resulting in frequent events of intense beach/barrier breaching, massive overwash and flooding. They are mainly expressed in sensitive areas which are subject to long-term erosional processes and comprise a low-lying profile and a narrow beach. This reflects the role of coastal morphology in controlling the intensity of storm-induced hazards along the deltaic coast. Shoreline evolution rates calculated during this period were significantly larger than the previously recorded ones, reflecting a pulsating erosion behavior where large pulses occur during stormy periods and are reduced during post-storm periods. Under the present scenario of maximum coastal development, storm-induced damage has been reported almost every year which could indicate that the present overall beach configuration status along the Catalan coast has reached its limit for protecting the hinterland against stormsThis work has been done in the framework of the VuCoMA research project funded by the Spanish Ministry of Science and Innovation (CTM2008-05597/MAR). We thank the Department of Territorial Policy and Public Works of the Autonomous Government of Catalonia and to Puertos del Estado (Spanish Ministry of Public Works) for supplying wave data used in this study. This work could not been done without the effort and generosity of La Vanguardia in digitizing and making available their archives to the public. The second and third authors were supported by PhD grants from the CSIC and the Spanish Ministry of Education respectivelyPeer reviewe

Impacts of sea-level rise-induced erosion on the Catalan coast

The Catalan coast as most of the developed Mediterranean coastal zone is characterized by the coincidence of stresses and pressures on the natural system with a high exposure and low adaptive capacity. Due to this, Climate Change-induced effects will increase natural hazards and aggravate their associated impacts and, in consequence, it is necessary to assess their effects for proper long-term management. In this work, we assess the impact of sea-level rise (SLR) induced shoreline retreat on the Catalan coast for three scenarios ranging from 0.53 m to 1.75 m by the year 2100. Implications are analyzed in terms of affectation of two main functions provided by beaches, i.e. recreation and protection. Obtained results show that CC will be a serious threat to analyzed functions since the expected enhanced shoreline retreat will severely decrease the recreational carrying capacity and, the capacity of protection in the near future under tested scenarios. The actual level of development along the coastal zone reduces the natural resilient capacity of beaches to SLR in such a way that, the lack of accommodation space can be identified as a main factor for the estimated impact

Mapping cumulative compound hydrometeorological and marine-induced risks on the NW Mediterranean coast

Abstract Coastal risks in the Mediterranean are a result of the complex interplay between hydrometeorological and marine hazards. The region encompasses areas with varying degrees of vulnerability to these hazards, as well as spatial variations in exposure values, making it essential to adopt a comprehensive and nuanced approach to risk assessment and management. It is worth noting that hydrometeorological hazards, such as flash floods, can often have a greater impact than strictly coastal hazards, highlighting the need to consider the full range of potential risks. Therefore, coastal managers must adopt a multi-hazard approach to make sound risk management decisions. This study addresses this need using an index-based framework that assesses the integrated risk in time and space (hereafter referred to as cumulative compound risk) in coastal zones by aggregating the main hydrometeorological and marine hazards, the vulnerability of the territory to both types of hazards, and values at exposure. The framework is designed for use at large spatial scales (applied to a 1100 km coastline in this study), with the basic spatial unit being relevant for management (here set as the municipality in this study). Its application enables the assessment of spatial variations in integrated risk as well as individual hydrometeorological and marine contributions. The combined use of the indices and cluster analysis helps identify similarities and differences in the risk profile of spatial units, and thus, define homogeneous areas from a risk management perspective. In this study, the framework was applied to the Spanish Mediterranean coastline, an area representative of the climatic, geomorphological, and socioeconomic conditions of the Mediterranean coast

Proposal for an Integral Quality Index for Urban and Urbanized Beaches

A composite index, based on function analysis and including thirteen sub-indices, was developed to assess the overall quality of urban and urbanized beaches in the Mediterranean area. The aggregation of components and sub-indices was based on two questionnaires completed by beach users and experts. Applying the new Beach Quality Index (BQI) demonstrated that the quality of beaches could be improved. In general, the strongest aspects of the beaches assessed were those related to short-term user demand, and the weakest were those related to the consequences of human pressure on the area, in particular, erosion problems. The composite index is intended to be used together with Environmental Management Beach Systems (EMBs) as a hierarchical management scorecard and in monitoring programs. This new tool could also make planning more proactive by synthesizing the state of the most important beach processes.Peer reviewe