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Tidal data forms the basis for understanding and quantifying sea-level rise and tidal statistics. While quality assurance methods based upon spectral and harmonic analysis have been applied to individual tidal records, these methods have not been used to assess global tidal datasets. In this thesis, four west coast tidal records were examined using harmonic analysis methods to investigate uncertainty on a monthly averaged basis. Uncertainty was identified using a method that quantifies time lag as a linear regression of height difference between a predicted and measured tidal height and the predicted rate of change of tidal height. Errors identified through this method were validated by visual inspection of qualitative records and digitization of daily staff/gauge comparisons. Of the 1188 total months investigated using the time-lag based estimates, 41 months of high uncertainty were identified validated through comparison with staff/gauge comparisons. Six additional months of high uncertainty were identified by the time-lag based method but were not apparent in staff-gauge comparisons. An additional 55 months of possibly inadequate data were only identified by staff/gauge comparisons. These 55 cases were shown to relate to either staff measurement error or short-term gauge issues. For problems that persisted over a month, a binning approach was used to create a statistically significant relationship between estimated time lag and the uncertainty in the water level measurement. In the future, this regression could be applied to assess uncertainty in other tidal datasets.

Στην παρούσα μεταπτυχιακή διατριβή προσπαθούμε να δώσουμε μια τάξη μεγέθους της παλιρροϊκής ενέργειας που υπάρχει στα παλιρροϊκά ρεύματα του Στενού Ρίου – Αντιρρίου και προτείνουμε την εγκατάσταση υδροστροβίλων “παλίρροιας” με την οποία θα μπορούσαμε να εξάγουμε την ενέργεια αυτή για να την εκμεταλλευτούμε ως ηλεκτρική ενέργεια στα σπίτια μας. Στο Κεφάλαιο 1, γίνεται μία εισαγωγή σχετικά με το φαινόμενο της παλίρροιας εξηγώντας τον τρόπο και τα αίτια που το δημιουργούν. Στο Κεφάλαιο 2, αναπτύσσονται κάποιες βασικές σχέσης υδραυλικής οι οποίες μας βοηθούν στον υπολογισμό της ταχύτητας και της ισχύς του παλιρροϊκού ρεύματος. Επίσης, γίνεται κατηγοριοποίηση των υδροστροβίλων ‘παλίρροιας’, καθώς παρουσιάζονται συγκεκριμένα μοντέλα εταιριών με τα τεχνικά χαρακτηριστικά τους. Στο Κεφάλαιο 3, περιγράφεται ο αλγόριθμος του οργανισμού EPRI, με τον οποίο γίνεται ο υπολογισμός της συνολικής μέσης ετήσιας παλιρροϊκής ενέργειας, η οποία μπορεί να είναι διαθέσιμη και να “εξαχθεί” από έναν υδατικό πόρο. Προτείνεται μια παραλλαγή της μεθόδου αυτής προσαρμοσμένη στα δικά μας δεδομένα και πραγματοποιείται σύγκριση μεταξύ των δύο. Στο Κεφάλαιο 4, παρουσιάζονται τα αριθμητικά και γραφικά αποτελέσματα για την ισχύ των παλιρροϊκών ρευμάτων του Στενού Ρίου – Αντιρρίου. Ορίζεται η περιοχή μελέτης και επικεντρωνόμαστε σε αυτή για την ανάλυση των χρονοσειρών της ταχύτητας των ρευμάτων. Στο Κεφάλαιο 5, παρουσιάζεται η εγκατάσταση τριών μοντέλων υδροστροβίλων στην περιοχή μελέτης. Τέλος, στο Κεφάλαιο 6, παρουσιάζεται μια περιβαλλοντική μελέτη για το έργο της εγκατάστασης υδροστροβίλων ‘παλίρροιας’ στο Στενό Ρίο – Αντιρρίου και παρατίθενται τα γενικά συμπεράσματα που προέκυψαν από τα προηγούμενα κεφαλαία. Παρατηρήσαμε, ότι η ισχύς του ρεύματος που μπορούμε να εξάγουμε από την περιοχή μελέτης που ορίσαμε είναι κατά μέση τιμή περίπου το 60% του μέγιστου επιτρεπτού που μπορούμε να εξάγουμε από τη συνολική διατομή του Στενού Ρίου - Αντιρρίου. Τα συστήματα των υδροστροβίλων, που προτείνονται μετά από την θεωρητική εφαρμογή τους στην περιοχή μελέτης, φαίνεται να μπορούν να καλύψουν με ηλεκτρική ενέργεια μεγάλο μέρος της περιοχής της Πάτρας. Οι δυσκολίες που θα έχουμε να αντιμετωπίσουμε στην περίπτωση της εγκατάστασης υδροστροβίλων “παλίρροιας” θα είναι ο τρόπος με τον οποίο θα τοποθετηθούν οι βάσεις των υδροστροβίλων στον πυθμένα, λόγω της σύστασης του πυθμένα, αλλά και οι αποστάσεις που θα πρέπει να τηρηθούν από τους πυλώνες της γέφυρας Ρίου – Αντιρρίου, το οποίο θα μπορούσε να λιγοστέψει τον αριθμό τον υδροστροβίλων που θα μπορούσαμε να εγκαταστήσουμε στο σύστημα. Τέλος, ένας σημαντικός παράγοντας που θα πρέπει να εξεταστεί είναι ότι ένα τέτοιο έργο μπορεί από περιβαλλοντικής άποψης να είναι θετικό, αλλά από οικονομικής πλευράς θα αύξανε αρκετά τους λογαριασμούς της Δ.Ε.Η, για λόγους συντηρήσεις, αρχικού κόστους εγκατάστασης, περιβαλλοντικών τελών κτλ. / -

As an artist, I am interested in understanding how and why humans interact with the natural world. I examine my own individual behaviors and practices and research impacts made on nature by humans as a whole. I am drawn to nature for a multitude of reasons, including aesthetic beauty, psychological wellness, unraveling the mysteries of the universe and trying to understand the origins of life. As an artist I explore the dialectic relationship between everything we perceive outside of ourselves as the environment, and the way we think of ourselves in relation to that environment. I believe in the interconnectedness of all living things and I am interested in understanding why humans are the only species which act against their best interests in preserving the habitat that is necessary for survival. These questions bring me to address the issues of greed, consumption, and control over resources in my art practice.

One challenge for Autonomous Underwater Vehicle (AUV) multibeam surveying is the limited ability to assess internal vertical agreement rapidly and reliably. Applying an external ellipsoid reference to AUV multibeam data would allow for field comparisons. A method is established to merge ellipsoid height (EH) data collected by a surface vessel in close proximity to the AUV. The method is demonstrated over multiple collection missions in two separate areas. Virtual tide corrector values are derived using EH data collected by a boat and a measured ellipsoid to chart datum separation distance. Those values are compared to measurements by a traditional tide gauge installed nearby. Results from the method had a mean difference of 6 centimeters with respect to conventional data and had a mean total propagated uncertainty of 15 centimeters at the 95% confidence interval. Methodologies are examined to characterize their accuracies and uncertainty contribution to overall vertical correction.

A variação do Nível Médio do Mar (NMM) é um assunto de grande importância para a sociedade, pois a sua elevação, que é verificada em diversas estações de monitoramento no mundo, pode trazer diversos prejuízos para o homem. Aponta-se como razão principal deste fenômeno a elevação da temperatura média do planeta causada pelo aumento da concentração dos Gases de Efeito Estufa (GEE). Em Cananéia, litoral sul do estado de São Paulo, o nível do mar vem sendo monitorado há mais de 50 anos através de um marégrafo. A estação também conta, desde o ano de 2002, com um receptor do Global Positioning System (GPS) cuja antena está instalada em um pilar adequado, engastado na rocha. Além disso, um gravímetro geodinâmico foi instalado junto à estação para, associado ao marégrafo e ao receptor GPS, contribuir para a determinação da variação absoluta do NMM, que representa a diferença entre os movimentos do nível do mar e da crosta. Com os dados maregráficos durante o período de 1954 a 2004 foi possível determinar um aumento relativo do NMM de 4,2 mm/ano, com a determinação de um modelo global de marés oceânicas que melhor se adaptou à região. A análise das observações gravimétricas permitiram a determinação de um modelo de maré terrestre para a estação, porém a deriva instrumental impediu a detecção de alguma tendência para a crosta. Já os resultados obtidos através do processamento das observações GPS entre os anos de 2004 e 2006 através do método Precise Point Positioning (PPP) determinaram um rebaixamento da crosta de 1,59 mm/ano. No entanto, este curto período de observações processadas impede que se conclua algo de definitivo sobre o movimento da crosta. / The Mean Sea Level (MSL) variation is very important for the society because its elevation, verified in many monitoring stations around the world, causes several damages for the humanity. It\'s pointed how principal reason of this phenomena the elevation of the world mean temperature due to greenhouse gases concentration increasing. At Cananéia, south coast of São Paulo, the sea level has been monitored for more than 50 years by a tide gauge. The station has since 2002 a GPS receiver whose antenna is installed in a stable pillar fixed in the bed rock. Moreover a geodynamic gravitymeter installed at the site of the station, out of the tide gauge and the GPS receiver, contributes for the determination of absolute variation of the MSL that represents the difference between the movement of the sea level and the crust. With tide gauge observations from 1954 to 2004 it was possible to find a relative increasing of MSL of 4.2 mm/year with the determination of the ocean tide model that best fit in the region. The analysis of gravimetric observations allowed the determination of an earth tide model but the instrumental drift hindered the detection of some crust tendency. However the results obtained by processing GPS observations between 2004 and 2006 by Precise Point Positioning showed a decrease of the crust of 1.59 mm/year. However, any definite conclusion on the crust movement need a longe period of observations with GPS.

O objetivo do trabalho é analisar a relação comunidade de Matarandiba, localizada no município de Vera Cruz Ilha de Itaparica, BA, com a morte e os mortos. A tese tornou-se uma reflexão sobre a comunidade através das relações estabelecidas com a morte, os mortos e a maré. Sendo assim, trata de dois tipos de gente: gente morta e gente do mar. Tendo a morte como sujeito de pesquisa, é inevitável que as dimensões da vida também se manifestem, cito: as atividades pesqueiras, a costura das relações de parentesco, as práticas religiosas, dentre outros aspectos. Discuto a técnica e a performance da morte e ao seguir esse caminho outras técnicas também ganharam espaço, a exemplo das técnicas da pesca e da mariscagem. Do ponto de vista teórico, o trabalho é uma proposta de diálogo entre a antropologia da performance e a antropologia da técnica. Utilizarei como base de reflexão a concepção de uma ecologia do sensível (INGOLD, 2017), para compreensão da técnica nos seus diferentes aspectos (morte, ritual e atividade pesqueira). Sete palmos, camadas ou capítulos compõem essa etnografia: 1) A morte de Teresa, 2) Os técnicos da morte e o cuidado com os mortos, 3) As narrativas sobre a morte, 4)Maré morta: corpo, técnica e movimento das marisqueiras, 5) O vento que dá na vela: a performance dos pescadores, 6) As donas das águas e 7) Tamarandiba ou as folhas vermelhas do mangue. / The main purpose of this work is to analyse the relation that has the comunity of Matarandiba, a place belonging to the city of Veracruz, to death an decesed people. While i work on the field, this thesis transformed into a reflexion about the community using the study of his relation to death, deads and the sea. I distinguished two types of people: The deceased (gente morta) and the one that are alive and at the sea (gente do mar). Having the death has subject implies to studies manifestation of life such as, fishing activities, familial relationship, religious practice, et so on. In this work, I devellop and question death as much as a tecnic that as a performance; therefore, other tecnics occupy a netral place in comunnotary life, like fishing or picking up seashells(mariscagem). Theoreticly speaking, this work is an invitation to create a dialogue between tecnical anthropology and performing anthropology. To do so, I used as a background the \"sensitive ecology\" (Ingold,2017), in order to compare tecnic in its diferents variants (death, rituals, fishing activities). There is 7 chapters i this ethnography : 1 Theresa\'s death; 2 Death tecnics and caring for the deaths; 3 Narativity about death; 4 Mare morte: body, tecnics and displacement of maquiserias; 5) Wind in the sail: Fisher\'s performance; 6) Mistresses of waters 7) Taramandiba or the red leafs of the mangrove.

It is necessary to subtracting the tidal height from the observed depth to derived real depth while conduct hydrographic survey. The tidal data can be collected by conventional tide gauge or by using real time kinematics (RTK) GPS survey in the near shore region. However, when setting up tidal instruments in the offshore areas, many restricts still remained due to many factors such as topography, weather, and sea state. On contrary, the RTK GPS survey method has the limitation on the radio transmitting range. Therefore, the tidal zone method integrates the tidal station data to calculate the offshore tide data which can solve these problems. Generally, the tidal zone is constructed by using real tidal station data around the narrow channel. But the tide data is not possible to integrate on both side of the Taiwan Strait due to the vertical datum is not identical due to current political separation. To overcome this problem, this study proposed tidal zone method based on the tidal height derived from a tide numerical model. The tidal zone method is consequently applied to improve the accuracy of the offshore hydrographic survey. After processing the tide data derived from the model output and performing harmonic analysis, this study utilized the analysis result to draw a co-tidal chart to demonstrate the tidal characteristics for the purpose of establishing the tidal zone of the Taiwan Strait. This study also accomplished correspondent tidal zones for all the tide stations of Taiwan west coast within 12 miles territorial waters. This study further proposed a virtual station method for offshore hydrographic survey tide correction which applied the analysis result of each numerical model grid point as a virtual tidal station to derive the offshore tide correction values with spatial continuous characteristics. This study selected three experiment areas based on the multi-beam echo sounder survey data acquired offshore Ma-Liuo tide station. The direct tide station correction, tidal zone correction, and virtual station correction methods are applied to the hydrographic survey data to evaluate the performance of the tidal zone and virtual station correction methods. According to the experiment results, the tidal zone and virtual station correction method improve 20 and 16 cm respectively over the direct tide station correction method in the offshore area with the distance 25 km to the Ma-Liuo tide station. It indicates that the feasibility of the tidal zone method and it can improve the hydrographic survey results significant while the tide characteristics are different. Tidal zone can provide the required information to decide a proper reference tide station according to the tidal characteristics for the hydrographic survey data post-processing.

Biogeographic patterns across a landscape are developed by the interplay of environmental processes operating at different spatial and temporal scales. This research investigated dynamics of salt marsh vegetation on the Skallingen salt marsh in Denmark responding to environmental variations at large, medium, and fine scales along both spatial and temporal spectrums. At the broad scale, this research addressed the importance of wind-induced rise of the sea surface in such biogeographic changes. A new hypothetical chain was suggested: recent trends in the North Atlantic Oscillation index toward its positive phase have led to increased storminess and wind tides on the ocean surface, resulting in increased frequency, duration, and magnitude of submergence and, hence, waterlogging of marsh soils and plants, which has retarded ecological succession. At the mid-scale, spatial patterns of vegetation and environmental factors were examined across tidal creeks. Sites closer to tidal creeks, compared to marsh interiors, were characterized by the dominance of later-successional species, higher bulk density, and lower nutrient contents and electrical conductivity. This finding implies that locations near creeks have experienced a better drainage condition than the inner marshes, which eventually facilitated the establishment of later-successional plants that are intolerant to physical stress. At the micro-scale, this research examined how the extent and mode of facilitation and competition vary for different combinations of plant species along physical gradients. Both positive and negative relationships were spatially manifested to a greater degree on the low marsh than on the mid marsh. This insight extends our current knowledge of scale-dependent interactions beyond pioneer zones to higher zones. On the low marsh, different types of bivariate point pattern (i.e., clustered, random, and regular) were observed for different combinations of species even at similar spatial scales. This finding implies that it is difficult to generalize at which scales competition and facilitation occur. To conclude, this research stresses the need for a holistic approach in future investigations of salt marsh biogeography. For example, based on results of this current research, it would be meaningful to develop a comprehensive simulation model that incorporates salt marsh ecology, geomorphology, and hydrology observed across scales.

The studies of tidal current and sea level variation in the Taiwan Strait are popular topics in recent years. The sea level data, to be applied to data analysis or model forcing and validation, are mostly observed in the near shore region. It is relative not easier to obtain real tidal data in the offshore area. This study intended to obtain sea level data within Taiwan Strait, using in-situ water depth measurements collected by EK500 of research vessels OR1, OR2 and OR3 during 1989-2003. The basic assumption of this work is that the changes of sea level and topographical depth equal to observed water depth. By using a large set of field measurements, it is possible to get bottom topography such that tidal data can be extracted by harmonic analysis of long-term discrete time series of water depth data. A total of 1513 cruises of water depth data were collected, which account for nearly 6 million samples. These data were screened through a series of criteria for quality control. Firstly, data were plotted cruise by cruise ( longitude vs latitude , longitude vs depth , time vs depth), then reasonable range of time, depth and region were choosed manually. Second, outliers, defined as values greater than 3 standard deviations on 5 point moving mean along the cruise track (or time), were replaced by linear interpolation values. Finally, a 2-minute moving average was applied to the along track time series water depth data. This step was trying to remove the effect of surface waves. The original huge records were reduced to about 550,000 valuable samples for the 1513 cruises data. According to the density distribution of water depth samples in Taiwan Strait, 32 sub-region were selected for topography and harmonic analyses. In each sub-region, the bottom topography was mapped by an optimal interpolation method through a Gaussian weighting function. The radius of Gaussian weighting function applied is 3 time of the distance of grid. Water depth samples subtracted topographical depth of nearby grid to form a set of sea level data ready for harmonic analysis. The phase and amplitude of semi-diurnal tides (M2) and diurnal tides (K1¡BO1) in each sub-region were computed for the 32 regions in Taiwan Strait. The water depth measurements derived sea level variations were compatible with that of a global tidal model (OSU) and a set of moored long-term pressure records in the middle of the strait. Especially, the tidal phase among these results were quite close. However, the tidal amplitudes of water depth data derived were smaller. Sensitivity analysis showed that the errors, differences between OSU model and depth derived sea levels, were small with regions of high density of water depth measurements. Both harmonic derived sea level variations and OSU model predictions indicated a southward propagating tidal wave, which matched with the scenario of Kevin wave propagation in Taiwan Strait. Our analysis also showed that the sea level variations in the northern part of the strait were dominated by M2 and K1 components while the southern part of the strait were dominated by M2 and O1 components.