Antonella Marsico

Some results of coastal defences monitoring by ground laser scanning technology

A general coastal retreat affects almost all the beaches of the Apulia region (southern Italy). In particular, the coastal strip of the Gulf of Manfredonia shows an evident retreat due to human activity. To control coastal erosion, several defence interventions have been realised: breakwaters, shore parallel defences, and, above all, several types of groynes (rectilinear, hook-shaped, T-shaped) were built along the shoreline in accordance with local request. Nowadays, there are about 300 coastal defences built up to protect against human activities. A laser scanner survey of these defences, using a Leica Geosystems HDS3000, was carried out between April 2006 and September 2008 to collect data about the beach profiles and changes occurring in the defence framework. The survey work consists of 3D rendering of defences in order to make comparisons between scans of different periods. Overlap between the points cloud of the whole coastline showed that defences preserved their own profile when no human interventions took place. Moreover, throughout the length of the investigated area, not a single trend occurred in the beach profile: according to the defence framework, some stretches of coast display advancing trend, while others are stable or retreating. Therefore, this preliminary study indicated that the changes that occurred in the beach profiles and defence structures are mainly due to human interventions.

Climatic characteristics of middle-southern Apulia (southern Italy)

Abstract Please click here to download the map associated with this article. The purpose of this work is to make a climatic map in order to show several variables concerning climate type in a Mediterranean region. The study is focused on the middle and southern part of Apulia region, southern Italy, an area of approximately 12,170 km2 between 39°45′ and 41°30′ N and 15°40′ and 18°40′ E. The map uses mean annual temperature as a background for the number of dry and cold months, and is supplemented with secondary maps which highlight the characteristics of a dry climate. Rainfall and temperature records of 46 thermo-pluviometric stations, over a 30 year period, were interpolated by kriging: the main map takes into account the Rapetti and Vittorini pattern, while for the other graphics the Thornthwaite and Mather water balance model was followed. Both these methods focus on factors which determine drought in a land of low rainfall such as Apulia region.

Flooding scenario for four Italian coastal plains using three relative sea level rise models

ABSTRACT The coastal areas of the central Mediterranean Sea are sensitive to climate change and the consequent relative sea level rise. Both phenomena may affect densely urbanized and populated areas, causing severe damages. Our maps show the land-marine flooding projections as effects of the expected relative sea level rise for four Italian coastal plains using (i) IPCC AR5 estimations, based on the IPCC RCP 8.5 emission scenarios and (ii) the Rahmstorf 2007 model. Isostatic and tectonic data were added to the global projections to estimate the relative sea changes expected along the coastline by 2100, as well as sea-flooding. The northern Adriatic map shows the study area, extending for about 5500 km2, and is presented at a scale of 1:300,000 with two inset maps at a scale of 1:150,000. The Oristano coastal plain is about 125 km2; the map scale is at 1:60,000 with an inset map scale at 1:33,000. The Cagliari coastal study area extends for 61 km2; the map scale is at 1:60,000 with two inset maps at 1:30,000. The Taranto area extends for 4.2 km2 and is represented at a scale map of 1:30,000, while the three inset maps are at a scale of 1:10,000.

Terrestrial Laser Scanning for 3D Cave Reconstruction: Support for Geomorphological Analyses and Geoheritage Enjoyment and Use

Recent developments in laser scanning techniques and digital modelling provide powerful tools for the knowledge, management and preservation of the underground. A Terrestrial Laser Scanner (TLS) survey was performed to create a 3D virtual model of the Santa Croce cave (Apulia, Southern Italy); this is well known for its Palaeolithic and Neolithic finds (a Neanderthal thigh-bone among all) and used as a showcave both for its natural and historic heritage. The survey included chimneys, passages and also the surface over the cave to acquire a model of the entire system. Data were acquired by processing the resulting points cloud to pursue three main purposes: karst hazard management, education and geoheritage preservation. Thanks to the virtual model, the opportunity to visit the site through a virtual tour, also showing hardly accessible details, is an exciting way to discover the underground environment. Therefore, interactive virtual image can be utilised to promote the site as an important tool to disseminate knowledge and to increase interest in the Earth sciences in society at large.

Evolution of the Ofanto River delta from the ‘Little Ice Age’ to modern times: Implications of large-scale synoptic patterns

We reconstruct the evolution of the Ofanto River delta from the 17th century to the present using historical maps (1600–1850), official IGM topographic maps (1850–1980) and recent aerial photographs (2015), and we compare long-term morphological changes with the evolution of the delta of the Volturno River during the same time period. The aim of this study is to define the role of climatic (flood frequency, synoptic pressure patterns) and anthropogenic factors (deforestation, anthropogenic sediment subtraction of river sediment) in the evolution of the Ofanto delta. We analysed the importance of each factor on the evolution of the delta and compared them with the simultaneous behaviour of the Volturno delta to highlight the role of large-scale synoptic pressure patterns. We found that the main driver of different delta evolution phases is weather-climatic condition, while anthropogenic factors interacted with the delta evolution in different ways but did not control the first-order evolution. In particular, analysing the data on recent floods, we found that the most favourable situations for both rivers are omega-blocking, deep low-pressure trough and strong meridional circulation (mode Ω) which create Mediterranean low-pressure systems. Instead, a zonal circulation (mode W) can only cause floods on Volturno. Because the evolution of a delta is driven by the frequency of floods, and because we found that the frequency of floods is guided by synoptic patterns, a relationship can be established between delta evolution and synoptic patterns in the past. Consequently, past phases of the contemporary progradation of the Ofanto and Volturno deltas suggest the increasing frequency of mode Ω, while phases of simultaneous progradation of the Volturno delta and stability and/or retreat of the Ofanto delta are indicative of the increasing frequency of mode W. The only exception occurred during the last evolutionary phase (60 years), when anthropogenic sediment subtraction was prevalent.

Integrated Geological and Digital Surveys to Know, Preserve and Promote a Geoheritage: the Sea Cliff of Vignanotica Bay (Gargano Promontory, Southern Italy)

The sea cliff of Vignanotica Bay (Gargano Promontory, Southern Italy) is a site that, for its peculiar geological features, can be considered a witness of geodiversity and that, as such, should be evaluated as geosite. Since it is necessary to first know, then enhance, and finally protect a geosite, here we propose a modern method of study aimed at the understanding and dissemination of geological knowledge to a wide audience of non-experts. The cliff, located in the Gargano National Park, was investigated using both stratigraphic-sedimentological and digital methods. The former method, realised using macrofacies and microfacies analysis, allowed us to study features of a deep-marine environment, characterised by subaqueous slides (slumpings). The latter method allowed us to achieve a virtual 3D model of the entire sea cliff, highlighting many geological features, often difficult to observe since they are exposed along high vertical walls. The combined use of these methods led to a complete characterisation of the cliff, useful both to promote geological knowledge and to preserve the site.

Erosion hazard assessment along the Capitolo coast (Monopoli, southern Italy)

Erosion affects about 25% of the coast of the Apulia region, with the severest consequences being along sandy coastlines. Beach retreat is mainly due to the decrease of solid material transport, the destruction of dune deposits and the building of docks that obstruct the longshore current. A survey was conducted around Capitolo, the main sandy coastline near Bari, to examine the hazards affecting beaches and to provide guidelines for the management of human activities along the coasts. The survey was carried out along a coastal stretch of about 3 km, extending in a South Easterly direction from 17° 21′ 30″ E, 40° 54′ 20″ N to 17° 23′ E, 40° 53′ 40″ N. The map, at a scale of 1:3000, shows three levels of hazard, determined as follows: (i) the state of preservation of the dunes and watercourses, based on the geomorphological map of the Apulia region; (ii) data collected from July 1989 to April 2008 by the Monopoli buoy of the National Wave Measuring Network; (iii) the shoreline change rates computed within a geographic information system (GIS). A matrix was established taking into account of these features, weighting each parameter in order to develop a hazard-level measurement for shoreline lengths of about 25 meters. The results show that all Capitolo beaches have a high level of shore preservation hazard. The results of this study should be a factor in any decisions made on the management of the present day village, both existing commercial activities and the future development of the area.