scholarly journals Coastal Modification in Relation to Sea Storm Effects: Application of 3D Remote Sensing Survey in Sanremo Marina (Liguria, NW Italy)

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1040
Author(s):  
Ilaria Ferrando ◽  
Pierluigi Brandolini ◽  
Bianca Federici ◽  
Antonio Lucarelli ◽  
Domenico Sguerso ◽  
...  

Integrated remote sensing techniques, such as photogrammetry from unmanned aerial vehicles (UAV), mobile laser scanners (MLS) and multibeam echosounders (MBES), are particularly effective in detecting and measuring coastal and seabed features and their modifications over time (4D analysis) induced by sea storms. In fact, these techniques allow the production of very high-resolution 3D models, with a continuum between above and below sea level. The present research is focused on the area of Portosole Marina (Sanremo, Western Liguria), affected by a severe sea storm in October 2018 and the following restoration. Two integrated 3D surveys were performed in February 2019 and in November 2019, obtaining accurate and reliable high-definition digital surface models (DSMs) in both emerged and submerged areas. The comparison between the two surveys highlighted volumetric changes in the seabed induced by the sea storm and the effects of a temporary worksite on the emerged and submerged breakwater. In particular, a total deficit of sediments of about 5000 m3 caused an average lowering of about 4 cm over the entire area, concurring with the breakwater instability. This study aims to contribute to the understanding of coastal system resilience within ongoing global climate changes, that is, increasing the intensity of extreme events in the Mediterranean area.

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2349 ◽  
Author(s):  
Carosi ◽  
Padula ◽  
Ghetti ◽  
Lorenzoni

Climate changes will lead to a worsening of the ecological conditions, in terms of hydrological instability and rising water temperatures, of the Mediterranean rivers. Freshwater fishes inhabiting this area can be threatened in the near future by accelerating drought and decreased ecological connectivity. The main aim of the research was to analyze changes in the distribution of the endemic freshwater fishes Padogobius nigricans, Squalius lucumonis and Telestes muticellus in the Tiber River basin (Italy), within a proven period of climate warming, in terms of increasing water temperature and droughts. A multivariate analysis was conducted using fish and environmental data collected in 117 sites over the years 1990–2017. For the three species, population abundance, age structure and body condition were analyzed. Detectability, occupancy, local extinction and colonization processes were also examined. We showed that S. lucumonis and T. muticellus have shifted their distributions upstream, likely in order to reach their thermal optimum. Padogobius nigricans did not move upstream significantly, since the species is characterized by limited vagility and thus a low dispersal capability in a context of high river fragmentation. In the study area, elevation and river barriers seem to play a key role in extirpation and colonization processes; for S. lucumonis and T. muticellus the extinction probability decreased with increasing altitude, while for P. nigricans the colonization probability decreased with an increasing degree of river fragmentation. These results highlight how species-specific dispersal ability can lead to varying adaptability to climate change.


2021 ◽  
Vol 8 (2) ◽  
pp. 27-35
Author(s):  
Vitalii Martyniuk ◽  
Olha Tomchenko

The problem of transformation of lakes of Polissya region under the influence of global climate changes, and also anthropogenic factors in basin systems (drainage reclamation, agrarian nature use and chemicalization of watershed soils, growth of residential lands, uncontrolled extraction of water from underground horizons, unauthorized extraction of amber, etc.), which lead to the reduction of water bodies, acceleration of sedimentation, eutrophication and, as a consequence, transformation into lake-swamp complexes are substantiated. The main stages of field researches, features of decryption of lakes by space images, the essence of the concept of «paleo-lake» and natural aquatic complex (NAC) have been revealed. An algorithm scheme of research of natural-anthropogenic transformations of the lake with the use of remote sensing and GIS technologies has been proposed. With the help of the Google Earth resource the estimation of changes of parameters of the areas of model lakes of Volyn Polissya is carried out, and on an example of Bilske lake the changes in the area of the reservoir from the «paleo-lake» to the modern boundaries of the shoreline and water area have been analyzed. The hydrological and limnological parameters of Bilske lake have been analyzed. Based on the analysis of high-resolution space images (Sentinel-1, Sentinel-2, Landsat) in different spectral channels, the ecological condition of the lake has been assessed by the vegetation index (NDVI), the dynamics of the thermal regime of the lake surface has been analyzed and the reservoir temperature changed during 2017-2021. A digital landscape map of Bilske lake, with the separation of aqua facies has been presented and landscape-assessment of NAC has been done. In the course of the research, the tendency to increase of temperatures of a reservoir has been established. The proposed approach using remote sensing tools to assess the ecological status of lakes is effective in methodological and practical terms. Along with instrumental and laboratory methods, it is expedient to use it for the creation of ecological passports of reservoirs, monitoring of lakes of reserved and recreational territories, long-term forecasting of development of aquatic complexes in the conditions of natural and anthropogenic transformations.


1999 ◽  
Vol 51 (3) ◽  
pp. 280-294 ◽  
Author(s):  
Dorit Sivan ◽  
Gedaliahu Gvirtzman ◽  
Eytan Sass

AbstractThe Quaternary deposits in the Galilee coastal plain comprise alternating calcareous sandstone, red loam, dark clay, and uncemented sand. The calcareous sandstone in the lower part of the sequence represents a Pliocene to early Pleistocene marine transgression, and is covered unconformably by the late Quaternary sequence. The base of this sequence has an estimated age of ∼500,000 yr. It is covered unconformably by marine calcareous sandstone in the west, which represents the global high sea-level stand of isotope stage 7.1, and is known as one of the “Tyrrhenian” events in the Mediterranean area. The overlying members represent the low sea-level stand of stage 6, the first a red paleosol indicating a relatively wet phase and the second an eolianite unit representing a drier phase. The eolianite forms longitudinal, subparallel ridges that formed contemporaneously. The overlying marine sandstone, which contains one of the diagnostic fossils of the “Tyrrhenian” events, the gastropodStrombus buboniusLMK, accumulated during the global high stand of stage 5.5. The last glacial period left no sedimentary record. The Holocene is represented by a marine clay unit that is covered by sand. The present study establishes a complete and detailed chronostratigraphic sequence for an eastern Mediterranean beach, which contains the gastropodS. buboniusLMK.S. buboniuson the Galilee coast is attributed to stage 5.5 and therefore, establishes an east–west Mediterranean correlation, which can be used for linking Mediterranean events to paleo-sea levels and global climate changes.


2020 ◽  
Vol 3 (1) ◽  
pp. 11-23 ◽  
Author(s):  
Abdulla Al Kafy ◽  
Abdullah Al-Faisal ◽  
Mohammad Mahmudul Hasan ◽  
Md. Soumik Sikdar ◽  
Mohammad Hasib Hasan Khan ◽  
...  

Urbanization has been contributing more in global climate warming, with more than 50% of the population living in cities. Rapid population growth and change in land use / land cover (LULC) are closely linked. The transformation of LULC due to rapid urban expansion significantly affects the functions of biodiversity and ecosystems, as well as local and regional climates. Improper planning and uncontrolled management of LULC changes profoundly contribute to the rise of urban land surface temperature (LST). This study evaluates the impact of LULC changes on LST for 1997, 2007 and 2017 in the Rajshahi district (Bangladesh) using multi-temporal and multi-spectral Landsat 8 OLI and Landsat 5 TM satellite data sets. The analysis of LULC changes exposed a remarkable increase in the built-up areas and a significant decrease in the vegetation and agricultural land. The built-up area was increased almost double in last 20 years in the study area. The distribution of changes in LST shows that built-up areas recorded the highest temperature followed by bare land, vegetation and agricultural land and water bodies. The LULC-LST profiles also revealed the highest temperature in built-up areas and the lowest temperature in water bodies. In the last 20 years, LST was increased about 13ºC. The study demonstrates decrease in vegetation cover and increase in non-evaporating surfaces with significantly increases the surface temperature in the study area. Remote-sensing techniques were found one of the suitable techniques for rapid analysis of urban expansions and to identify the impact of urbanization on LST.


Author(s):  
Pontus Lurcock ◽  
Fabio Florindo

Antarctic climate changes have been reconstructed from ice and sediment cores and numerical models (which also predict future changes). Major ice sheets first appeared 34 million years ago (Ma) and fluctuated throughout the Oligocene, with an overall cooling trend. Ice volume more than doubled at the Oligocene-Miocene boundary. Fluctuating Miocene temperatures peaked at 17–14 Ma, followed by dramatic cooling. Cooling continued through the Pliocene and Pleistocene, with another major glacial expansion at 3–2 Ma. Several interacting drivers control Antarctic climate. On timescales of 10,000–100,000 years, insolation varies with orbital cycles, causing periodic climate variations. Opening of Southern Ocean gateways produced a circumpolar current that thermally isolated Antarctica. Declining atmospheric CO2 triggered Cenozoic glaciation. Antarctic glaciations affect global climate by lowering sea level, intensifying atmospheric circulation, and increasing planetary albedo. Ice sheets interact with ocean water, forming water masses that play a key role in global ocean circulation.


The Condor ◽  
2021 ◽  
Author(s):  
Natália Stefanini Da Silveira ◽  
Maurício Humberto Vancine ◽  
Alex E Jahn ◽  
Marco Aurélio Pizo ◽  
Thadeu Sobral-Souza

Abstract Bird migration patterns are changing worldwide due to current global climate changes. Addressing the effects of such changes on the migration of birds in South America is particularly challenging because the details about how birds migrate within the Neotropics are generally not well understood. Here, we aim to infer the potential effects of future climate change on breeding and wintering areas of birds that migrate within South America by estimating the size and elevations of their future breeding and wintering areas. We used occurrence data from species distribution databases (VertNet and GBIF), published studies, and eBird for 3 thrush species (Turdidae; Turdus nigriceps, T. subalaris, and T. flavipes) that breed and winter in different regions of South America and built ecological niche models using ensemble forecasting approaches to infer current and future potential distributions throughout the breeding and wintering periods of each species. Our findings point to future shifts in wintering and breeding areas, mainly through elevational and longitudinal changes. Future breeding areas for T. nigriceps, which migrates along the Andes Mountains, will be displaced to the west, while breeding displacements to the east are expected for the other 2 species. An overall loss in the size of future wintering areas was also supported for 2 of the species, especially for T. subalaris, but an increase is anticipated for T. flavipes. Our results suggest that future climate change in South America will require that species shift their breeding and wintering areas to higher elevations in addition to changes in their latitudes and longitude. Our findings are the first to show how future climate change may affect migratory birds in South America throughout the year and suggest that even closely related migratory birds in South America will be affected in different ways, depending on the regions where they breed and overwinter.


2021 ◽  
Vol 10 (8) ◽  
pp. 500
Author(s):  
Lianwei Li ◽  
Yangfeng Xu ◽  
Cunjin Xue ◽  
Yuxuan Fu ◽  
Yuanyu Zhang

It is important to consider where, when, and how the evolution of sea surface temperature anomalies (SSTA) plays significant roles in regional or global climate changes. In the comparison of where and when, there is a great challenge in clearly describing how SSTA evolves in space and time. In light of the evolution from generation, through development, and to the dissipation of SSTA, this paper proposes a novel approach to identifying an evolution of SSTA in space and time from a time-series of a raster dataset. This method, called PoAIES, includes three key steps. Firstly, a cluster-based method is enhanced to explore spatiotemporal clusters of SSTA, and each cluster of SSTA at a time snapshot is taken as a snapshot object of SSTA. Secondly, the spatiotemporal topologies of snapshot objects of SSTA at successive time snapshots are used to link snapshot objects of SSTA into an evolution object of SSTA, which is called a process object. Here, a linking threshold is automatically determined according to the overlapped areas of the snapshot objects, and only those snapshot objects that meet the specified linking threshold are linked together into a process object. Thirdly, we use a graph-based model to represent a process object of SSTA. A node represents a snapshot object of SSTA, and an edge represents an evolution between two snapshot objects. Using a number of child nodes from an edge’s parent node and a number of parent nodes from the edge’s child node, a type of edge (an evolution relationship) is identified, which shows its development, splitting, merging, or splitting/merging. Finally, an experiment on a simulated dataset is used to demonstrate the effectiveness and the advantages of PoAIES, and a real dataset of satellite-SSTA is used to verify the rationality of PoAIES with the help of ENSO’s relevant knowledge, which may provide new references for global change research.


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