Abstract Understanding the dynamics of sea surface variation and its direct effects on the coastal population has been a central issue of study for oceanography in conjunction with other areas of geosciences. One of the main challenges in a changing global ocean is continuously monitoring on an adequate scale that can detail locally varying phenomena. This study reviews the methods to obtain coastal topo-bathymetric data and the tools available to produce flood maps and coastal sea-level rise monitoring models. The advantages and limitations of the main tools are described, highlighting the difficulties related to implementation time and financial investment in contrast to the quality of the obtained data. A case study of the Paranaguá Estuarine Complex — of great environmental, economic, and tourism importance — is presented as its sea-level fluctuations have been poorly studied. For this reason, we describe the Paranaguá Estuarine Complex, highlighting and discussing the structural and methodological challenges and the lack of resources that limit the possibilities of a detailed study of the Paranaguá Estuarine Complex from the point of view of natural disasters, thus stimulating the debate on the necessary actions to address climate change at the local level. geosciences phenomena topobathymetric topo bathymetric sealevel level models described environmental economic studied reason disasters

ABSTRACT Sandy beaches have different shoreline change rates (i.e., erosion/accretion rates). An erosive process on beaches poses risks for human-occupied areas. One example is Matinhos Beach (state of Paraná - Brazil), which has an average annual erosion rate of around 1.5 m yr-1 This study applied a methodology that combines in situ measurements and numerical modeling to simulate the physical processes in the coastal area of Matinhos during the 2018 Austral winter. Monthly DGPS surveys were carried out in the study area from June to September. The MOHID modeling system was applied to simulate hydrodynamics and sediment transport, considering waves and tidal forcing validated with in situ data. The WAVEWATCH III and SWAN models were applied in a nesting approach to simulate the waves at Matinhos Beach. The GFS was used to assess the wind conditions. The study period showed a dynamic evolution of accretion and erosion between monthly measurements with no clear pattern in most profiles. Significant sand accumulation was observed near the headland. Morphological changes were minor due to the predominance of low energy without significant storm events. The measured morphological changes are in line with the residual littoral drift obtained from the modeling results for the period. The residual current velocities were towards the southwest, with magnitudes ranging from 0.15 m s-1 to 0.2 m s-1. A slight variation in the angle of wave incidence (10°) may change the direction (southwest or northeast) and intensity of the littoral drift. The applied methodology can reduce uncertainty and support effective coastal management. However, the seasonal scales of wave climate cannot be disregarded, nor can the need for coastal oceanographic data. i.e., ie i e (i.e. erosionaccretion rates. . rates) humanoccupied human occupied areas state Brazil, Brazil , Brazil) 15 1 5 1. yr1 yr yr- 201 winter September transport data conditions profiles headland events southwest 015 0 0.1 s1 s s- 02 2 0. s1. 10° 10 (10° northeast management However disregarded i.e. (i.e 20 01 (10 i.e (1 (

ABSTRACT Sandy shorelines show heightened susceptibility to alterations, highlighting the importance of reliable field measurements in forecasting coastal evolution. This study offers direct hydrodynamic measurements from the upper shoreface of a sandy beach in Paraná. We observed five distinct oceanographic conditions, including a high-energy event. Notably, wave height showed a positive correlation with northward longshore currents. During pre- and post-frontal periods, cross-shore flow predominates over longshore currents, particularly evident during low tides with pronounced offshore flow. These findings provide valuable insights for researchers seeking to quantify and model longshore sediment transport dynamics and morphological changes along sandy coastlines. alterations evolution Paraná conditions highenergy high energy event Notably currents pre postfrontal post frontal periods crossshore cross shore coastlines

Abstract The aim of this study is to assess the morphological evolution of the Ararapira (Brazil) barrier-inlet system, at different time scales. Based on satellite imagery, elevation data, and in-situ observations, we quantify the morphological evolution of the region. Results show that the Ararapira inlet migrated continuously southwards, moving updrift, with erosion at its southern margin and intercalated erosion and accretion at the northern margin. At approximately 5.5 km north of the old inlet, the gradual narrowing of the sandy barrier due to channel meandering and coastal erosion resulted in its breaching, in August 2018. We document the initial stages of the new inlet, which after opening, presents intense erosion at its southern margin, resulting in the channel widening to ~1 km. After the barrier breaches, the system begins to adjust to a new equilibrium condition, with the widening of the new inlet being balanced by the gradual closure of the old inlet. These drastic environmental changes control the functioning of such systems, and our results provide important background information for their use and management.

A quantificação de processos de transporte de pequena escala e a compreensão de como eles afetam o padrão espacial dos constituintes ópticos da água são peça chave no funcionamento de um ecossistema costeiro. A variação espacial e local de propriedades físicas e bio-ópticas da água foi analisada durante um ciclo de maré de sizígia do verão austral, bem como as estimativas do transporte advectivo e dispersivo de sal na secção transversal da boca dos subestuários Mederiros e Itaqui. Estes subestuários fazem parte do Sistema Estuarino de Paranaguá, sul do Brasil, e também integram a reserva da biosfera. Ambos os subestuários foram classificados com Tipo 1a, bem misturados com pouco estratificação. As variações da salinidade estão em fase com o nível da água, e a propagação da onda de maré se dá na forma de uma onda estacionária. Os perfis verticais de velocidade mostraram pouco cisalhamento vertical, e a intensidade da componente u de velocidade variou semidiurnamente. O transporte de sal estuário acima foi dominado pela difusão da maré em uma coluna de água instável. O ambiente óptico apresentou uma dominância mista dos componentes opticamente ativos, como indicado pelos coeficientes de absorção dos materiais dissolvidos e particulados. A matéria orgânica dissolvida colorida (CDOM) apresentou um comportamento conservativo com dominância da luz abaixo de 500 nm em Medeiros, enquanto que no subestuário Itaqui as partículas não algais foram dominantes na faixa azul . A contribuição do fitoplâcton é alta na faixa do vermelho e aumenta em função da intrusão salina. Contudo, devido à influência da descarga de água doce e a ressupensão de sendimentos induzida por processos físicos as concentrações dos componentes ópticos na coluna d'água geralmente não apresentam uma relação simples entre si.

Measuring small-scale physical processes and how they affect the spatial patterns of sea water's optical constituents plays a key role in understanding the functioning of complex coastal ecosystems such as estuaries. The spatial variations of physical and bio-optical water properties were investigated during one spring tidal cycle in austral summer, on two transects across the channel of the Medeiros and Itaqui sub-estuaries. These sub-estuaries are a biosphere reserve, and part of the Paranaguá Estuarine System, located on the Southern Brazilian coast. Both sub-estuaries were classified as Type 1a, wellmixed with low stratification. The salinity variations are in phase with the water level, and the tidal propagation is well represented by a standing wave. The vertical velocity profiles showed little vertical shear, and the intensity of the u-component of the velocity varied semi-diurnally. The upper estuary salt transport was dominated by tidal diffusion in an unstable water column. The optical environment presented a mixed dominance of optically active substances, as indicated by the absorption coefficients of dissolved and particulate matter. The colored dissolved organic matter (CDOM) showed overall conservative behavior and was dominant in light absorption below 550 nm in the Medeiros, while nonalgal particles play the most important role in light absorption in the Itaqui in the blue absorption band. The phytoplanktonic contribution is prominent in the red domain and increases as a function of saline intrusion. However, due to the influence of freshwater discharge and the re-suspension of bottom sediments induced by physical processes, the concentrations of the optical components in the water column do not generally have any simple relationships between them.

Baixios representam riscos a navegação no interior dos estuários. Portanto, devem ser bem delineados e tais informações devem ser freqüentemente atualizadas. Métodos hidrográficos tradicionais têm dificuldade em cobrir áreas rasas devido sua extensão e relevo. Uma alternativa é o uso de imagens de satélites para mapear essas áreas, com as vantagens de baixo custo e rápido resultado. No setor norte do Complexo Estuarino de Paranaguá o último levantamento batimétrico foi realizado na década de 50 e um novo mapeamento destas áreas, mesmo sem a acurácia das cartas náuticas, é de utilidade para o planejamento de estudos, modelagem ambiental e navegação de pequenas embarcações. Este estudo teve o objetivo de avaliar o potencial de gerar mapa batimétrico das áreas rasas da Baía das Laranjeiras, através do sensoriamento remoto. A aplicação deste método é fácil e mostrou-se bastante útil em regiões onde não existem dados batimétricos ou estes precisam ser atualizados. O mapa obtido é bastante fiel dentro dos limites batimétricos que se pretende, entre 0,36 e 4,5 m de profundidade, principalmente considerando que 75% do complexo estuarino possui profundidade inferior a 5 m.

Shallow waters represent potential risks to navigation inside estuaries. Therefore, they must be well described and data must be always updated. Traditional hydrographic methods have difficult to cover shallow areas due to them extension and low relief. An alternative is the use of satellite images for mapping the areas, with the advantage of low cost and quick results. In the north area of the Paranaguá Estuarine Complex the last bathymetric survey was in the 50's so a new bathymetric mapping of these areas, even without the nautical chart's accuracy, is useful for studies planning, environmental modeling and small boats navigation. This study had the objective of generate bathymetric map of shallow areas in the Laranjeiras bay through remote sensing. The application of this method is not difficult and could be very useful in regions were there is no bathymetric data or need to be updated. The map obtained is very realistic inside the limits of 0,36 to 4,5 m water depth and important considering that nearly 75% of the Paranaguá Estuarine Complex have depths less than 5 m.