Morphodynamics Evolution of the Urban Beaches of Rio de Janeiro, Brazil city.

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Agenor Cunha Silva, Camille Brito Pinto, Ruan Vargas, Fábio Ferreira Dias This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4713442/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This article deals with morphodynamics and sedimentation on urban sandy beaches. It focuses on the relationship between depositional dynamics on the beaches of Arpoador, Ipanema and Leblon, in the south zone of the city of Rio de Janeiro, Brazil. The coast morphological evolution described here is a function of sedimentation processes and the width variation on the beaches sand strip. Sediments are evaluated from eighteen beach samples collected from six transect beach profiles to verify the predominant sediment types. Coastal morphodynamics is described based on depositional processes on the morphological beach’s evolution. The morphology evolution is depicted from historical satellite images. Meteorological and oceanographic data reflect the depositional dynamics of beaches under different climatic conditions. Granulometric analysis is used here to determine the grain size, standard deviation, skewness values, and kurtosis. The areas of erosion and deposition of the beaches are shown by maps with the points most susceptible to the negative effects of storms and climate change. The depositional dynamics that occur at the same time alternately between the studied beaches is also analysed to improve the understanding of the depositional processes. On some occasions, the reduction of sand on Arpoador beach occurs at the same time as the accumulation of sand in the area in front of Jardim de Alah beach. On some occasions, the channel connecting the Rodrigo de Freitas Lagoon with the sea is closed. It is hoped that a better understanding of the depositional processes discussed here can be used to facilitate the management and preservation of urban beaches. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 1. INTRODUCTION The urban beaches are studied here in relation to their morphology and the dynamics of sedimentation processes, which in general reflect characteristics and aspects of the internal continental shelf ocean (Silva, 2009). The currently the morphology of beaches has been changed more rapidly perhaps due to climate changes. This research aims to expand the knowledge of the depositional dynamics of the main urban beaches of the south zone of the city of Rio de Janeiro. It is hoped that the recording of morphological variations and a better knowledge of the granulometry of sediments will facilitate the delimitation of critical areas of depositional processes on the beaches. Several studies on beach evolution have already addressed relationships between morphological changes and sedimentological processes in coastal environments. (Fox & Davis. 1974, Short. 1979, Rosman & Valentini. 1989 e Sunamara. 1988). The mechanisms involved in the dynamic beaches balance are not yet fully known; let alone of the beaches in urban environments (Calliari & Klein. 1993). It is urgent to know whether, on beaches where sediments are in constant mobilization, adopting the coastline as a reference is valid to assess the intensity of depositional processes. Recent studies of coastal depositional processes confirm that knowledge of oceanographic factors should not dispensed (Souza et al. 2005). We know that the types and textures of sediments are controlled by waves. On beaches, the upper limit of grain mobility is the area of wave expansion, and at sea, the level of the wave base limits sediment transport. These boundaries define areas of intense sediment transport along the beaches (Suguio. 2010). Some beaches may have undefined features due to different depositional behaviour; A shoreline with a single beach arch can have stretches with erosion, accretion, and stability at the same time. (Toldo et al. 1999, Esteves et al. 2002). At a glance on morphodynamics coastal processes the beach evolution are affect by wave climate and their approach shoreline angle. When the waves approach to the beaches the waves type can accumulate or remove sediments from different sectors of a beach arc in short times. (Lima et al. 2001). Historical satellite images and field surveys is to describe the depositional dynamics and most sensitive sedimentation beach processes. Lately, research on beach depositional processes has been used in coastal area protection projects. When erosion events result in the reduction of the width of the beaches, it poses risks to the buildings and the population of these areas. (Muehe, D. & Döbereiner,1957). 1.1 C oastal waves The knowing about wave height and period as well as where the waves come from of the open ocean to reach the beach is very important to determine the climate of waves. To know about the wave energy distributed on a beach helps know the deposicional processes and the beaches dynamic evolution. The direction, height, and period of the dominant waves on a beach exerts great influence on its plant and profile. When the wave conditions vary, corresponding adjustments occur in beach morphology. (Bird, 1996). Shoreline position have been used like a key parameter of a beach state, often used as a descriptor of the response of the system to changes in external forcing, such as sea-level rise (Luque et all, 2023). Beaches are highly variable natural systems present along world coasts, formed by the accumulation of unconsolidated sediments shaped by the simultaneous action of waves, water levels, and currents (Short, 1999). In the study region, atmospheric and marine processes mobilize the sediment in a special way, continuously reshaping the features of the beach. Although the concept of dynamic equilibrium is not the main the protagonist of this study, the action of depositional processes is considered as an equilibrium factor where the distribution of sediments changes in a short period of time. However, for each instantaneous forcing conditions, an instantaneous theoretical equilibrium state can be defined, as the one that would be reached in the hypothetical case of those conditions remaining unchanged. 2. STUDY AREA The beaches located in the southern zone of the city of Rio de Janeiro, Brazil make up the study area. The beaches of this region have the after-beach occupied by buildings and avenues parallel to the coastline with a sidewalk that limits this urban area with the strip of sand of the beaches. A sidewalk connects the two neighbourhoods of Ipanema and Leblon. The sediment collect limits are given by this sidewalk that connects important neighbourhoods of the study area the Ipanema and Leblon. The mean sea level is the survey limit for the sea. These boundaries form a continuous strip of sand from the beaches of Ipanema to Leblon, being interrupted only by a narrow flow channel that connects the ocean to the only coastal lagoon in the region, the Rodrigo de Freitas Lagoon. The characteristic of the beach arch adjusts to the orientation of the coast (east-west). The Arpoador and Leblon beaches occupy the same beach arch as a single large beach almost rectilinear coast where the coastal drift occurs according to the approach of the ocean waves. The sandy strips of the study area are evaluated here based on the variations in the size of the beaches in the short period of time. These are the beaches where the research were development. Beach profiles were used to samples collect carried out in the beach arch. The between profiles space is 600meters approximately and 4.5 metres between the samples on the beach profile. 2.1 Weather in the study area. Local weather observation shows that oceanographic and meteorological conditions affect the beaches in particular ways. The west east direction of the coastline is a straight with the winds patterns of northeasterly (NE) where winds of the South Atlantic semipermanent anticyclone predominate. On some occasions this situation is interrupted by frontal weather systems when the prevailing wind changes this direction to SW. The dominance of the SW winds is immediate, and the waves climate are affecting the distribution of sediments too. - During the fieldwork, it was observed that the sediment mobilization was due to oceanographic and meteorological conditions prevailing in the region. This situation is showed when the cold fronts change the weather the oceanographic conditions affecting the beach morphology. The morphologic variation on the sand strip width dimension reflects the variation in the wave direction. The variations occur as the wave approach (Parente, 1969). The wave climate and the wind regime information comes from the Forecast Service of the Brazilian Navy's Hydrography Center (CHM). Satellite images allow check how the waves of the sea approach to the coast. Under different conditions of good and bad weather the sediments can be mobilized from the Arpoador to the Leblon when the sea waves on good whether condition come from the southeast or on bad weather comes from the Leblon to the Arpoador when the waves come from the southwest direction. These different climatic situations are described below for the south zone of the city of Rio de Janeiro. A) good weather conditions - are present when sea waves come from the Southeast and a system of low atmospheric pressure predominates in the area. Weather Conditions associated with the East (E) waves with the dominant South Atlantic Anticyclone high pressure system are shown in Figure 02. B) bad weather conditions - when sea waves come from the Southwest and a system of low atmospheric pressure predominates in the area. This is the situation when the waves of Southwest (SW) and South (S), occur with cold fronts, followed by extratropical cyclones, from Southeast (SE), the bad weather becomes predominant in the study area. The waves come to the beach from a different directions. Comes to the beaches from Southwest (SW) and the South (S) directions (Figure3). 3. MATERIAL AND METHOD The material and method used here includes bibliographic surveys, environmental data, satellite historical images and sediment granulometric laboratory data. The fieldwork involves sampling collects, laboratory analyses and Sediment processing data. 3.1 Fieldwork sample collect. The collects of the surface sediment samples were made in special way. On the beach the sand samples were obtained in six transect profiles (A-F). Three (3) samples were collected in each profile distributed between the waterfront sidewalk and the sea waterline. The eighteen (18) surface sediment samples make up the total data distributed along the Leblon-Arpoador beach arch as follows: Sample 1 – closer to the sidewalk. Sample 2 – between the sidewalk and the sea, Sample 3 – closest to the waterline. The location of the sediment samples collect points (Fig. 4 ) was made by GPS (E-TREX GARMIN) in the WGS-84 data, obtaining the coordinates at the reduction level (NR) of the area, with spatial variation between 1 and 10m, of precision. The weight of each sample was 250g of material packed in plastic bags with GPS georeferenced tags. 3.2 Laboratory sediment analysis. The analysis of the sediment samples was done by granulometry with the washing, drying, and sieving of the collected material to determine the parameters of granulometry of the sediments. These data were considered in conjunction with environmental information on. 3.3 Sediment processing data. The laboratory work has been to determine the characteristics of sediments in coastal environments (Silva, 1985). Sediment classification and granulometry were by sieving (Wentworth, 1922). The determination of the granulometric parameters was obtained from the calculation of the values of mean diameter, standard deviation (selection), skewness, and kurtosis (Folk & Ward, 1957). 3.4 Oceanographic data. Wave and coastal currents information were obtained on the Mereological Service of Brazilian Navy. The oceanography in the area shows two specific patterns to the beach waves approach according with the weather conditions in this coastal region. Coastal currents or coastal drift are the mobilization of sediments along the coast by the action of waves when they approach the beach at a specific angle. In this sense, the sediment transport in the area occurs parallel to the shoreline by bidirectional flows. 3.5 Weather data. The predominant transport of sediments is available under good weather conditions when drift currents act on sediments from Arpoador beach to Leblon beach or from East (E) to West (W). However, when the weather changes and cold fronts reach this region, the coastal drift is altered. The sediment transport is now from West (W) to East (E); from Leblon beach to Arpoador beach. 4 RESULTS The results of the sediment analysis are show by the particle size values obtain to the eighteen (18) georeferenced samples. Three (3) surface samples were collected in each of the 6 (six) transect beach profiles. 4.1 Sedimentology. The results of the sediment analysis are show on Table 1 . The particle size values obtain to the eighteen (18) georeferenced samples. Three (3) surface samples were collected in each of the 6 (six) transect beach profiles. Table 1 Granulometric results to the beach sediments Arpoador – Leblon 06/17/2013) Indicators Coordinates Granulometric parameters. Profile Samples N E mean grain size standart deviation skewness Kurtosis 1 A1 681872 7456599 1,25 0,73 0,07 0,82 A2 681872 7456571 0,75 0,68 0,14 0,84 A3 681872 7456535 0,25 0,63 -0,05 0,76 2 B1 682088 7456689 1,25 0,5 -0,16 1,2 B2 682088 7456666 1,25 0,72 -0,37 1,01 B3 682088 7456650 1,05 0,78 -0,01 0,6 3 C1 682712 7456846 0,75 0,43 -0,22 1,23 C2 682719 7456817 1,75 0,82 -0,41 0,59 C3 682725 7456795 0,25 0,55 0,23 0,9 4 D1 683440 7456853 1,25 0,45 -0,17 1,13 D2 683437 7456826 1,25 0,48 -0,15 1,15 D3 683434 7456799 0,75 0,62 -0,37 0,85 5 E1 684691 7456785 1,25 0,47 -0,12 1,28 E2 684689 7456749 0,75 0,52 -0,13 1,18 E3 684687 7456768 0,25 0,49 0,17 0,99 6 F1 685358 7456566 1,75 0,42 0,18 0,93 F2 685354 7456535 1,25 0,42 -0,19 1,13 F3 685350 7456505 1,05 0,46 -0,31 1,43 4.2. G ranulometric parameters The sedimentary dynamics is the distribution of the granulometric parameters (Fig. 05). Mean values calculated for each of six collection profile (A-F) in PHI-fi units are presented. Variations of the depositional conditions are relative to the granulometric distribution of the sands in the sediments of the beaches from Arpoador to Leblon. Grain size diameter. The results of the particle size analysis revealed that in this stretch of the coast there is a predominance of fine sands with medium sands. The grain size sands variation is shown by a graph that seeks to show the relationship between the grain sizes and the sandy strip dimension of the beaches. This granulometric chart shows the grain mean size values to the sediment collection profiles. The dynamics of the depositional processes verified by graphic of the mean size of grains showed that the sediment’s variation of the sandy range in the collection profiles. It is concluded that the samples are classified as medium to fine sand, reflecting the moderate action of the waves along the coastline. Sorting (standard deviation). This measure basically revealed the intensity of the depositional processes. A graph of the standard deviation (selection) allows to verify the sorting grain distribution. The highest standard deviation values indicate less selected sediments occurs in the Leblon beach area. The selection of grains increases towards Arpoador beach. The predominance of well-selected sediments in the area of Arpoador beach occurs due to the oceanic circulation of the high seas that reaches this area with higher wave energy. Skewness. T his is a particle size parameter that can also be associated with the size of the grain of sand. The results show variations in the skewness values distribution with a predominance of negative skewness grains. Sediments with positive skewness predominate only around Leblon beach. The granulometry results show that the Leblon beach skewness is a parameter clearly affected by the physical environmental conditions of the morphology of this area. The predominance of higher energy waves and longshore current are associated with the morphological factor. In this area the greater beach gradient favours the presence of larger and more angular grains. In this area the smallest grains of sand are mobilized and removed by the greater intensity of the depositional processes. Kurtosis. T he results of this parameter show as a property the variations of the grain size distribution curves associated with the "degree of peak. Curves which are more peaked than the normal distribution curve are termed “leptokurtic”; Those that are flatter than normal are said to be "platykurtic".This measurement can be related to energy levels and expresses conditions of depositional dynamics associated with particle scattering and size. kurtosis is a measure that depicts the degree of sharpness of the peaks in the distribution curves in relation to the normal distribution. In the case studied here, the platicurtic and leptocurtic distributions occur respectively on the beaches of Leblon and Arpoador. In the Ipanema beach, the mesocurtic condition predominate, tending towards normal distribution. 4.3 Beach morphology Morphodynamics studies shown the evolution of beach morphology under different degrees of vulnerability to erosion according to different beach typologies. (Souza, 2007). Although sandy sediments predominate on the beaches studied, the evolution of depositional processes in the study area presents an unusual dynamic sedimentation condition. On the beaches of Arpoador and Leblon the sedimentation processes occur alternately. The wave energy acts on the depositional events of reduction (erosion) or enlargement (deposition) of the beaches. At same time and alternately the depositional events change the width of the strip of sand on the beach of Arpoador and the beach of Leblon. The depositional dynamics with sediment remobilization observed in the study área reinforces the depositional processes in the adjustment of the coastline to the beach forms (Hoefel, 1998). Beach morphodynamics studies have been used in the management and solution of environmental problems related to the morphology of sandy beaches (Muehe, 1979). From the granulometric parameters and beach measurements was possible obtain indicators that reflect the local morphodynamics (WRIGHT & SHORT, 1984). In this sense, from the granulometric parameters and beach measurements the results showed that the variations in the size of the sand strip of the beaches occur due to the inconstant depositional processes of the sea state. From the granulometric parameters and beach measurements the results showed that the variations in the size of the sand strip of the beaches occur due to the inconstant depositional processes of the sea state. (Table 02 ). The beach arch morphology Arpoador to Leblon shows that the circulation cells to the coastal drift meet the prevailing weather conditions. In this region the coastal currents change their origins from barlamar to sotamar when the angles of action of the waves on the coast are alternated. The coastal dynamics are affected by the depositional events of accumulation and removal of the sands that proportionally alter the size of the beaches. (Taggart & Schwartz 1988). 4.4 Arpoador and Leblon the beaches evolution. The beach measurements in historical satellite images (Google Earth) allowed to evaluate the dynamics of the beaches under different sedimentation conditions. The granulometric parameters distribution and the average values of the width of the beaches are fundamental items to determine the evolution of the depositional processes. From these items it becomes possible to define how these processes act on the morphology reducing or expanding the strip of sand and the size of the beaches. In a specific table presented below shows the data of the beach dimension values in centimetres that allow to evaluate the evolution of the depositional processes by the variation of the width in the Arpoador and Jardim de Alah beaches since the year 2000. The variation in the width of the beaches of Arpoador and Leblon (Jardim de Alah) is shown in Table 02 . Table 02 – The depositional events and width of the beaches since the year 2000. Year observation Arpoador beach Leblon beach Dimension Beach width Variation (38.99) Deposition (D) Erosion (E) Dimension Beach width Variation (108.07) Deposition (D) Erosion (E) 2000 21,04 17,65 D 125,72 -17,95 E 2002 54,46 -3,6 E 104,47 15,47 D 2003 59,97 -10,02 E 98,05 20,98 D 2004 29,05 0,82 D 108,89 -9,94 E 2005 31,39 -4,74 E 103,33 -7,6 E 2006 48,34 0,66 D 108,73 9,35 D 2007 52,66 -5,7 E 102,37 13,67 D 2008 25,03 0,94 D 109,01 -13,96 E 2009 22,52 -1,72 E 106,35 -16,47 E 2010 33,13 -1,19 E 106,88 -5,86 E 2011 18,01 15,74 D 123,81 -20,98 E 2012 29,93 2,86 D 110,93 -9,06 E 2013 56,72 0,06 D 108,13 17,73 D 2014 63,54 -11,76 E 96,31 24,55 D Mean-> 38,99 ------- 108,07 -------- The Fig. 06 shows the values recorded for the variation in the size of the beaches. It reflects tthe depositional dynamics events on the Arpoador and Jardim de Alah beaches since the year 2000 until 2014. It is possible to verify and relate sedimentation events (erosion or deposition) to the accumulation or removal of sediments on these beaches. 4.5 Monthly width variation of the beaches. Monthly satellite beach width measurements were made during hangover times are listed in Table 03 . This result defines how depositional processes act in periods of greater marine agitation in the reduction or expansion of beaches (Christopher and Andrew,2020). Surf events accumulate sand and widen the area in front of the Jardim de Alah channel while reducing the strip of sand on Arpoador beach by erosion (Anex 1). The storm events accumulate sand at the entrance of the channel that connects the Rodrigo de Freitas lagoon to the sea, resulting in the widening of the sand strip in the front area of the beach of the Jardim de Alah channel. This is a situation that requires constant work by dredgers to free the channel for drainage and renewal of the lagoon waters. Table 03 Hangover season beach width variation (Arpoador 1 / Leblon 2) Year month Arpoador value 1 Alah value 2 2004 5 40,01 -5,79727 95,01 -3,66727 2005 5 42,95 -2,85727 105,21 6,53273 2005 9 40,07 -5,73727 106,58 7,90273 2005 12 54,27 8,46273 97,63 -1,04727 2006 5 49,63 3,82273 110,96 12,28273 2007 9 41,34 -4,46727 105,21 6,53273 2008 8 40,31 -5,49727 95,54 -3,13727 2009 5 46,66 0,85273 83,57 -15,1073 2009 6 38,55 -7,25727 104,85 6,17273 2009 9 58,58 12,77273 104,88 6,20273 2010 1 51,51 5,70273 76,01 -22,6673 Mean 45,80727 98,67727 The results of the measurements are shown in Fig. 08. These are values of the mean values variations of the beaches size of Arpoador and Jardim de Allah. They reflect the depositional processes. It is possible to verify the times of greater intensity of the hangovers when the morphology of the beaches is more altered. May is the month in which the depositional processes are most evident. Erosive processes occur with greater frequency and intensity in two periods: May to June and August to September are periods of the greatest change in the beach’s morphology. In Fig. 07 it is possible to verify which months were of greater occurrence of hangovers and from the average values for each of the two researched beaches verify the months in which the width of the sand strips on the beaches of Arpoador and Jardim de Alah was affected between 2004 and 2010. It is interesting to note that in some years hangovers have occurred more than once. 5. CONCLUSIONS / RECOMMENDATIONS The results of this work have demonstrated evident relationships between sedimentation processes and coastal morphology (Bertalanffy, 1968; Bennett and Chorley, 1978; Phillips, 1992). Morphological knowledge of coastal environments should include continuous monitoring of depositional processes, considering that these processes can be rapidly altered by natural and anthropogenic causes. Records of variations in beach width and grain size confirm the erosive events and the morphological changes of the beaches. Especially when large oceanic waves occur in periods of sea hangover. In the area of study, morphological dynamics show that depositional processes always act continuously (Taggart & Schwartz,1988). The depositional processes act at the same time to remove or accumulate sands at different points of the same beach arch. In times of hangovers the sands accumulate, and the strip sand of the beach widens in the front of the channel of the Garden of Alah. At critical hangover moments the sea-lagoon channel connection is closed preventing the renewal of the waters of the Rodrigo de Freitas Lagoon with the sea. The bigger hangovers are the periods of big changes in the morphology of the beaches. The hangover times recorded in the Figure 8 showed that the month of May, in the autumn season is when the marine agitation acts on the beaches with greater intensity. The results obtained demonstrate that the evolution of beach morphology presents unique aspects in relation to depositional processes with beach segments that respond differently to storm waves in hangover seasons. The annex 1 shows the figures of simultaneous images of the beaches of Arpoador and Jardim de Alah in times of hangover. They depict how the size of these beaches has their sandy strips altered by depositional processes with the different sedimentation conditions that occur at the same time. The sedimentary dynamics present distinct depositional patterns for the two main beaches along the Arpoador – Leblon beach arch. • - In the area of Arpoador beach the strip of sand is reduced and almost disappears putting constructions of the waterfront in danger. • - In the area of Jardim de Alah, the accumulation of sediments expands the sandy strip and begins to obstruct the channel connecting the sea with the Rodrigo de Freitas Lagoon, requiring dredging and removal of sand. Considering that the indicators of morphodynamics processes had been demonstrate significant variations in beach forms, it is recommended that urban beaches be monitored more frequently. Especially in hangovers times, when the depositional processes are more intense (Annex 2). Meteorological and Oceanographic factors along with anthropic actions affect the depositional processes on the coast. It is recommended that projects focus on maintenance and preservation of beaches including as a priority an approach that balances an engineering perspective with the purely geological perspective (komar, 1976). In the study área the knowledge of coastal morphodynamics evolution is fundamental to protect beaches from extreme depositional events mainly in relation to the: know the physical factors make more easily the knowledge of the depositional processes that act on the stability of the littoral contours.. beach features that should be carried out more often mainly by the climatic rigors that affect with greater intensity engineering works and coastal depositional processes. extreme events such as those of 2008 on Arpoador beach. In addition to reducing the strip of sand by intense waves, this event hit the sidewalk and caused material damage to the residents and frequenters of that beach, depositional processes are part of the coastal dynamics to restore the morphology of the beaches to the new features after hangover events, works or anthropic actions of fattening (Leblon beach), In view of the above, it is recommended that the coastal forms defined by the positioning of the coastline, whenever possible, should be characterized in the light of oceanographic conditions at different times of the year and in function: - sedimentation processes, - physical factors, and - of anthropic actions In this way, a new concept of ban coastline is admitted, integrating sustainable methods of coastal protection and development of cities, New challenges and opportunities arise to create ways of protecting coastal spaces in urban environments, Maintaining public spaces and leisure areas implies a more qualitative and integrated relationship with the waters and with the changing coastal dynamics, The success of water resources management depends on the continuous monitoring of physical factors. The uncertainty of climate change and the disorderly occupation trends of urban coastal areas require us to seek more efficient methods of control and prevention to mitigate the adversities that are increasingly intense in coastal urban environments. The application and use of the concepts developed through the study of beach morphodynamics can be efficient in solving problems related to sandy beaches. It is concluded that in the study beaches the sediment samples fall mainly in the field of medium sand to fine sand, which indicates a moderate wave action along the shoreline of these areas. RECOMMENDS From the results obtained in this work it is possible to recommend guidelines to mitigate issues of the management of urban beaches. The study of beach morphology should consider variations in beach size by monitoring based on the following items: Physical factors affecting the sedimentary balance and stability of coastal contours, Oceanographic factors by variations in wave energy over time that affects seasonally eroding and silting the shoreline, Environmental factors such as the anthropic presence that in tourist areas that can alter the coastal depositional processes, Declarations Author Contribution Agenor was the main authorFábio Ferreira Dias, reviewer of the article and contributor of changesCamille and Ruan were responsible for mapping the area on the GIS References Christopher, J. Hein, Andrew, D. Ashton. 2020. 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Muehe, D. 1979, Sedimentology and topography of ahigh energy coastal environment between Rio de Janeiro and Cabo Frio, Brazil. An. Acad. Bras.Cienc. ,51(3):473-481. Muehe, D. 2001, Critérios Morfodinâmicos para o Estabelecimento de Limites da Orla Costeira para fins de Gerenciamento. Revista Brasileira de Geomorfologia,Volume 2, Nº 1. Parente, C. E. 1999, Uma nova técnica espectral para análise direcional de ondas . Março 1999. Tese (Doutorado em Física) - Universidade Federal do Rio de Janeiro, Rio de Janeiro Phillips, J.D. 1992, Nonlinear dynamical systems in geomorphology: revolution or Evolution, Geomorphology, 5, 219-29,01 Shepard, F. P. 1950, Beach cycles in Southern California. Beach Erosion board. Technical Memorandum, n. 20, 1950, 26p. Short, 1979. Three dimensional beach stage model. Journal of Geology. Short, A. D., 1999. Beaches. in Handbook of Beach and Shoreface Morphodynamics (ed Short, A. D.), 3–20 (John Wiley & Sons, Great Britain, 1999) Silva, A.C. 1985, Sedimentação e morfologia do fundo da plataforma continental interna nas proximidades da Ilha do Cabo Frio, RJ. Dissertação (Mestrado em Geografia) – IGEO, UFRJ, Rio de Janeiro. 189 p. Silva, A.C. 2009, Dinâmica Batimétrica e Sedimentológica da Região do Cabo Frio – Estado do Rio de Janeiro. Tese: Dotourado em Geologia : UFRJ / IGEO, 2009 21, 154 p.: il.; 30cm Souza, C.R.G. 2007, Determination of net shore-drift cells based on textural and morfological gradations along foeshore sandy beaches. Journal of Coastal Research. SUGUIO, Kenitiro. 2010, Geologia sedimentar do Quaternário e mudanças ambientais. São Paulo: Ofi cina de Textos. Sunamara, T. 1988, Beach morphologies and their changr. In: Horikawa, K. (ed). Nearshore dynamics and Coastal Processes. [S.J.]: University of Tokoyo. Taggaart, B.E. Schwartz, M. L 1988, Net shore drift direction determination: a systematic approach. Journal of shoreline management, 3(4), 285-309. Toldo, E. E.; Dillenburg, S. R.; Almeida, L. E. S. B.; Tabajara, L. L.; Martins, R. & Cunha, L. O. B. P. 1993,. Parâmetros morfométricos da Praia de Imbé, RS. Pesquisas, 20(1):27-32. Toldo Jr. EE, Almeida LES, Barros C e MartinsLR. 1999. Retiro do Litoral do Rio Grande do SulZona, Brasil. Em: Martins LR e Santana CI(Ed.), Recursos Não Vivos do Sul do Brasil-Zona Costeira e Margem Continental. Porto Alegre, Brasil: Editora da UFRGS, p.62-68. Torres JR, A. R. 1995, Resposta da Ressurgência Costeira de Cabo Frio a Forçantes Locais. Dissertação de Mestrado apresentada à COPPE/UFRJ. Wentworth, C.K. 1922, A Scale of Grade and Class terms for clastic sediments, Journal of Geology, 30:377-392 p. Wright, L D. & Short, A.D. 1984, Morphodynamic variability of surf zones and beaches: a synthesis. Marine Geology, 56, 93-11 Additional Declarations No competing interests reported. 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The red arrow is the direction of the drift currents to the sediment mobilization.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/b7e025381b94e1cb74c1e4d0.png"},{"id":62189279,"identity":"8fd968e2-5d37-48e5-8889-c451ad8a8791","added_by":"auto","created_at":"2024-08-10 12:20:58","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":372319,"visible":true,"origin":"","legend":"\u003cp\u003eBad Weather Situation – the yellow arrow is the direction of the waves coming from\u003c/p\u003e\n\u003cp\u003ethe SW. The red arrow is the direction of the drift currents to the sediment mobilization.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/192bd8ec5ba86296564c8857.png"},{"id":62186225,"identity":"10434254-da0d-4852-ae1e-41e79b97ce14","added_by":"auto","created_at":"2024-08-10 12:04:58","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":378448,"visible":true,"origin":"","legend":"\u003cp\u003eThe six (6) profile location of the sediment samples collect.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/e106013753bcc3a34a997910.png"},{"id":62186222,"identity":"9d7c69dc-2d10-4685-a2b9-a0a28c797f1f","added_by":"auto","created_at":"2024-08-10 12:04:58","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":139068,"visible":true,"origin":"","legend":"\u003cp\u003eGranulometric parameters. Beach Profiles (A-F) Arpoador-Leblon:\u003c/p\u003e\n\u003cp\u003eA. Grain size diameter; B. Sorting ; C. Skewness; D. Kurtosis.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/79c873753f26ac5d353dd8a2.png"},{"id":62187895,"identity":"4da1a90f-8bfa-45af-a3d8-63915a325009","added_by":"auto","created_at":"2024-08-10 12:12:58","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":115874,"visible":true,"origin":"","legend":"\u003cp\u003eMorphodynamics beaches variation Arpoador and Jardim de Alah.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/c0b707d687893debb05bec2a.png"},{"id":62186227,"identity":"c3156781-c456-4a66-aee0-f5819e38bf4b","added_by":"auto","created_at":"2024-08-10 12:04:58","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":60916,"visible":true,"origin":"","legend":"\u003cp\u003eBeaches monthly variation of the depositional processes.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/2c391d44a9308b43326a98bf.png"},{"id":62712236,"identity":"078b285a-6a16-4914-942f-7d02027a27fa","added_by":"auto","created_at":"2024-08-18 11:18:56","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2477231,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/cb8f3043-b9f4-4e81-a1c3-b95f46f134ce.pdf"},{"id":62186221,"identity":"43e3accf-840d-44ef-b94d-3dd821b020ea","added_by":"auto","created_at":"2024-08-10 12:04:58","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":1344992,"visible":true,"origin":"","legend":"","description":"","filename":"ANNEXI.docx","url":"https://assets-eu.researchsquare.com/files/rs-4713442/v1/371eb71b4c12f425d7279806.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Morphodynamics Evolution of the Urban Beaches of Rio de Janeiro, Brazil city.","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cp\u003eThe urban beaches are studied here in relation to their morphology and the dynamics of sedimentation processes, which in general reflect characteristics and aspects of the internal continental shelf ocean (Silva, 2009). The currently the morphology of beaches has been changed more rapidly perhaps due to climate changes. This research aims to expand the knowledge of the depositional dynamics of the main urban beaches of the south zone of the city of Rio de Janeiro. It is hoped that the recording of morphological variations and a better knowledge of the granulometry of sediments will facilitate the delimitation of critical areas of depositional processes on the beaches. Several studies on beach evolution have already addressed relationships between morphological changes and sedimentological processes in coastal environments. (Fox \u0026amp; Davis. 1974, Short. 1979, Rosman \u0026amp; Valentini. 1989 e Sunamara. 1988). The mechanisms involved in the dynamic beaches balance are not yet fully known; let alone of the beaches in urban environments (Calliari \u0026amp; Klein. 1993). It is urgent to know whether, on beaches where sediments are in constant mobilization, adopting the coastline as a reference is valid to assess the intensity of depositional processes. Recent studies of coastal depositional processes confirm that knowledge of oceanographic factors should not dispensed (Souza et al. 2005). We know that the types and textures of sediments are controlled by waves. On beaches, the upper limit of grain mobility is the area of wave expansion, and at sea, the level of the wave base limits sediment transport. These boundaries define areas of intense sediment transport along the beaches (Suguio. 2010). Some beaches may have undefined features due to different depositional behaviour; A shoreline with a single beach arch can have stretches with erosion, accretion, and stability at the same time. (Toldo et al. 1999, Esteves et al. 2002). At a glance on morphodynamics coastal processes the beach evolution are affect by wave climate and their approach shoreline angle. When the waves approach to the beaches the waves type can accumulate or remove sediments from different sectors of a beach arc in short times. (Lima et al. 2001). Historical satellite images and field surveys is to describe the depositional dynamics and most sensitive sedimentation beach processes. Lately, research on beach depositional processes has been used in coastal area protection projects. When erosion events result in the reduction of the width of the beaches, it poses risks to the buildings and the population of these areas. (Muehe, D. \u0026amp; D\u0026ouml;bereiner,1957).\u003c/p\u003e \u003cdiv id=\"Sec2\" class=\"Section2\"\u003e \u003ch2\u003e\u003cb\u003e1.1\u003c/b\u003e C\u003cb\u003eoastal waves\u003c/b\u003e\u003c/h2\u003e \u003cp\u003eThe knowing about wave height and period as well as where the waves come from of the open ocean to reach the beach is very important to determine the climate of waves. To know about the wave energy distributed on a beach helps know the deposicional processes and the beaches dynamic evolution. The direction, height, and period of the dominant waves on a beach exerts great influence on its plant and profile. When the wave conditions vary, corresponding adjustments occur in beach morphology. (Bird, 1996).\u003c/p\u003e \u003cp\u003eShoreline position have been used like a key parameter of a beach state, often used as a descriptor of the response of the system to changes in external forcing, such as sea-level rise (Luque et all, 2023).\u003c/p\u003e \u003cp\u003eBeaches are highly variable natural systems present along world coasts, formed by the accumulation of unconsolidated sediments shaped by the simultaneous action of waves, water levels, and currents (Short, 1999). In the study region, atmospheric and marine processes mobilize the sediment in a special way, continuously reshaping the features of the beach. Although the concept of dynamic equilibrium is not the main the protagonist of this study, the action of depositional processes is considered as an equilibrium factor where the distribution of sediments changes in a short period of time. However, for each instantaneous forcing conditions, an instantaneous theoretical equilibrium state can be defined, as the one that would be reached in the hypothetical case of those conditions remaining unchanged.\u003c/p\u003e \u003c/div\u003e"},{"header":"2. STUDY AREA","content":"\u003cp\u003eThe beaches located in the southern zone of the city of Rio de Janeiro, Brazil make up the study area. The beaches of this region have the after-beach occupied by buildings and avenues parallel to the coastline with a sidewalk that limits this urban area with the strip of sand of the beaches. A sidewalk connects the two neighbourhoods of Ipanema and Leblon. The sediment collect limits are given by this sidewalk that connects important neighbourhoods of the study area the Ipanema and Leblon. The mean sea level is the survey limit for the sea. These boundaries form a continuous strip of sand from the beaches of Ipanema to Leblon, being interrupted only by a narrow flow channel that connects the ocean to the only coastal lagoon in the region, the Rodrigo de Freitas Lagoon. The characteristic of the beach arch adjusts to the orientation of the coast (east-west). The Arpoador and Leblon beaches occupy the same beach arch as a single large beach almost rectilinear coast where the coastal drift occurs according to the approach of the ocean waves. The sandy strips of the study area are evaluated here based on the variations in the size of the beaches in the short period of time. These are the beaches where the research were development. Beach profiles were used to samples collect carried out in the beach arch. The between profiles space is 600meters approximately and 4.5 metres between the samples on the beach profile.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.1 Weather in the study area.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Local weather observation shows that oceanographic and meteorological conditions affect the beaches in particular ways. The west east direction of the coastline is a straight with the winds patterns of northeasterly (NE) where winds of the South Atlantic semipermanent anticyclone predominate. On some occasions this situation is interrupted by frontal weather systems when the prevailing wind changes this direction to SW. The dominance of the SW winds is immediate, and the waves climate are affecting the distribution of sediments too.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e- During the fieldwork, it was observed that the sediment mobilization was due to oceanographic and meteorological conditions prevailing in the region. This situation is showed when the cold fronts change the weather the oceanographic conditions affecting the beach morphology. The morphologic variation on the sand strip width dimension reflects the variation in the wave direction. The variations occur as the wave approach (Parente, 1969). The wave climate and the wind regime information comes from the Forecast Service of the Brazilian Navy\u0026apos;s Hydrography Center (CHM). Satellite images allow check how the waves of the sea approach to the coast. Under different conditions of good and bad weather the sediments can be mobilized from the Arpoador to the Leblon when the sea waves on good whether condition come from the southeast or on bad weather comes from the Leblon to the Arpoador when the waves come from the southwest direction. These different climatic situations are described below for the south zone of the city of Rio de Janeiro.\u003c/p\u003e\n\u003cp\u003eA) \u003cstrong\u003e\u003cu\u003egood weather conditions\u003c/u\u003e\u003c/strong\u003e - are present when sea waves come from the Southeast and a system of low atmospheric pressure predominates in the area. Weather Conditions associated with the East (E) waves with the dominant South Atlantic Anticyclone high pressure system are shown in Figure 02.\u003c/p\u003e\n\u003cp\u003eB) \u003cstrong\u003e\u003cu\u003ebad weather conditions\u003c/u\u003e\u003c/strong\u003e - when sea waves come from the Southwest and a system of low atmospheric pressure predominates in the area. This is the situation when the waves of Southwest (SW) and South (S), occur with cold fronts, followed by extratropical cyclones, from Southeast (SE), the bad weather becomes predominant in the study area. The waves come to the beach from a different directions. Comes to the beaches from Southwest (SW) and the South (S) directions (Figure3).\u003c/p\u003e"},{"header":"3. MATERIAL AND METHOD","content":"\u003cp\u003eThe material and method used here includes bibliographic surveys, environmental data, satellite historical images and sediment granulometric laboratory data. The fieldwork involves sampling collects, laboratory analyses and Sediment processing data.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Fieldwork sample collect.\u003c/h2\u003e \u003cp\u003eThe collects of the surface sediment samples were made in special way. On the beach the sand samples were obtained in six transect profiles (A-F). Three (3) samples were collected in each profile distributed between the waterfront sidewalk and the sea waterline. The eighteen (18) surface sediment samples make up the total data distributed along the Leblon-Arpoador beach arch as follows:\u003c/p\u003e \u003cp\u003eSample 1 \u0026ndash; closer to the sidewalk.\u003c/p\u003e \u003cp\u003eSample 2 \u0026ndash; between the sidewalk and the sea,\u003c/p\u003e \u003cp\u003eSample 3 \u0026ndash; closest to the waterline.\u003c/p\u003e \u003cp\u003eThe location of the sediment samples collect points (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e4\u003c/span\u003e) was made by GPS (E-TREX GARMIN) in the WGS-84 data, obtaining the coordinates at the reduction level (NR) of the area, with spatial variation between 1 and 10m, of precision. The weight of each sample was 250g of material packed in plastic bags with GPS georeferenced tags.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Laboratory sediment analysis.\u003c/h2\u003e \u003cp\u003eThe analysis of the sediment samples was done by granulometry with the washing, drying, and sieving of the collected material to determine the parameters of granulometry of the sediments. These data were considered in conjunction with environmental information on.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Sediment processing data.\u003c/h2\u003e \u003cp\u003eThe laboratory work has been to determine the characteristics of sediments in coastal environments (Silva, 1985). Sediment classification and granulometry were by sieving (Wentworth, 1922). The determination of the granulometric parameters was obtained from the calculation of the values of mean diameter, standard deviation (selection), skewness, and kurtosis (Folk \u0026amp; Ward, 1957).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.4 Oceanographic data.\u003c/h2\u003e \u003cp\u003eWave and coastal currents information were obtained on the Mereological Service of Brazilian Navy. The oceanography in the area shows two specific patterns to the beach waves approach according with the weather conditions in this coastal region. Coastal currents or coastal drift are the mobilization of sediments along the coast by the action of waves when they approach the beach at a specific angle. In this sense, the sediment transport in the area occurs parallel to the shoreline by bidirectional flows.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.5 Weather data.\u003c/h2\u003e \u003cp\u003eThe predominant transport of sediments is available under good weather conditions when drift currents act on sediments from Arpoador beach to Leblon beach or from East (E) to West (W). However, when the weather changes and cold fronts reach this region, the coastal drift is altered. The sediment transport is now from West (W) to East (E); from Leblon beach to Arpoador beach.\u003c/p\u003e \u003c/div\u003e"},{"header":"4 RESULTS","content":"\u003cp\u003eThe results of the sediment analysis are show by the particle size values obtain to the eighteen (18) georeferenced samples. Three (3) surface samples were collected in each of the 6 (six) transect beach profiles.\u003c/p\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003e4.1 Sedimentology.\u003c/h2\u003e\n \u003cp\u003eThe results of the sediment analysis are show on Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. The particle size values obtain to the eighteen (18) georeferenced samples. Three (3) surface samples were collected in each of the 6 (six) transect beach profiles.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eGranulometric results to the beach sediments Arpoador \u0026ndash; Leblon 06/17/2013)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"8\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eIndicators\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eCoordinates\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003eGranulometric parameters.\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eProfile\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSamples\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emean grain size\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003estandart deviation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eskewness\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eKurtosis\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eA1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e681872\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456599\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eA2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e681872\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456571\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,84\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eA3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e681872\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456535\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,76\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eB1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e682088\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456689\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eB2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e682088\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456666\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eB3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e682088\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456650\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e682712\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456846\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,23\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e682719\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456817\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e682725\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456795\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e683440\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456853\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e683437\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456826\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e683434\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456799\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,85\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e684691\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456785\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,28\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e684689\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456749\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e684687\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456768\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,99\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e685358\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456566\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,93\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e685354\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456535\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e685350\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7456505\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0,31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,43\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003e\u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003e4.2. G\u003c/span\u003eranulometric parameters\u003c/h2\u003e\n \u003cp\u003eThe sedimentary dynamics is the distribution of the granulometric parameters (Fig. 05). Mean values calculated for each of six collection profile (A-F) in PHI-fi units are presented. Variations of the depositional conditions are relative to the granulometric distribution of the sands in the sediments of the beaches from Arpoador to Leblon.\u003c/p\u003e\n \u003cul\u003e\n \u003cli\u003e\n \u003cp\u003e\u003cstrong\u003eGrain size diameter.\u003c/strong\u003e\u003c/p\u003e\n \u003c/li\u003e\n \u003c/ul\u003e\n \u003cp\u003eThe results of the particle size analysis revealed that in this stretch of the coast there is a predominance of fine sands with medium sands. The grain size sands variation is shown by a graph that seeks to show the relationship between the grain sizes and the sandy strip dimension of the beaches. This granulometric chart shows the grain mean size values to the sediment collection profiles. The dynamics of the depositional processes verified by graphic of the mean size of grains showed that the sediment\u0026rsquo;s variation of the sandy range in the collection profiles. It is concluded that the samples are classified as medium to fine sand, reflecting the moderate action of the waves along the coastline.\u003c/p\u003e\n \u003cul\u003e\n \u003cli\u003e\n \u003cp\u003e\u003cstrong\u003eSorting\u003c/strong\u003e (standard deviation).\u003c/p\u003e\n \u003c/li\u003e\n \u003c/ul\u003e\n \u003cp\u003eThis measure basically revealed the intensity of the depositional processes. A graph of the standard deviation (selection) allows to verify the sorting grain distribution. The highest standard deviation values indicate less selected sediments occurs in the Leblon beach area. The selection of grains increases towards Arpoador beach. The predominance of well-selected sediments in the area of Arpoador beach occurs due to the oceanic circulation of the high seas that reaches this area with higher wave energy.\u003c/p\u003e\n \u003cul\u003e\n \u003cli\u003e\n \u003cp\u003e\u003cstrong\u003eSkewness.\u003c/strong\u003e\u003c/p\u003e\n \u003c/li\u003e\n \u003c/ul\u003e\n \u003cp\u003e\u003cstrong\u003eT\u003c/strong\u003ehis is a particle size parameter that can also be associated with the size of the grain of sand. The results show variations in the skewness values distribution with a predominance of negative skewness grains. Sediments with positive skewness predominate only around Leblon beach. The granulometry results show that the Leblon beach skewness is a parameter clearly affected by the physical environmental conditions of the morphology of this area. The predominance of higher energy waves and longshore current are associated with the morphological factor. In this area the greater beach gradient favours the presence of larger and more angular grains. In this area the smallest grains of sand are mobilized and removed by the greater intensity of the depositional processes.\u003c/p\u003e\n \u003cul\u003e\n \u003cli\u003e\n \u003cp\u003e\u003cstrong\u003eKurtosis.\u003c/strong\u003e\u003c/p\u003e\n \u003c/li\u003e\n \u003c/ul\u003e\n \u003cp\u003e\u003cstrong\u003eT\u003c/strong\u003ehe results of this parameter show as a property the variations of the grain size distribution curves associated with the \u0026quot;degree of peak. Curves which are more peaked than the normal distribution curve are termed \u0026ldquo;leptokurtic\u0026rdquo;; Those that are flatter than normal are said to be \u0026quot;platykurtic\u0026quot;.This measurement can be related to energy levels and expresses conditions of depositional dynamics associated with particle scattering and size. kurtosis is a measure that depicts the degree of sharpness of the peaks in the distribution curves in relation to the normal distribution. In the case studied here, the platicurtic and leptocurtic distributions occur respectively on the beaches of Leblon and Arpoador. In the Ipanema beach, the mesocurtic condition predominate, tending towards normal distribution.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003e\u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003e4.3\u003c/span\u003e Beach morphology\u003c/h2\u003e\n \u003cp\u003eMorphodynamics studies shown the evolution of beach morphology under different degrees of vulnerability to erosion according to different beach typologies. (Souza, 2007). Although sandy sediments predominate on the beaches studied, the evolution of depositional processes in the study area presents an unusual dynamic sedimentation condition.\u003c/p\u003e\n \u003cp\u003eOn the beaches of Arpoador and Leblon the sedimentation processes occur alternately. The wave energy acts on the depositional events of reduction (erosion) or enlargement (deposition) of the beaches. At same time and alternately the depositional events change the width of the strip of sand on the beach of Arpoador and the beach of Leblon.\u003c/p\u003e\n \u003cp\u003eThe depositional dynamics with sediment remobilization observed in the study \u0026aacute;rea reinforces the depositional processes in the adjustment of the coastline to the beach forms (Hoefel, 1998). Beach morphodynamics studies have been used in the management and solution of environmental problems related to the morphology of sandy beaches (Muehe, 1979). From the granulometric parameters and beach measurements was possible obtain indicators that reflect the local morphodynamics (WRIGHT \u0026amp; SHORT, 1984). In this sense, from the granulometric parameters and beach measurements the results showed that the variations in the size of the sand strip of the beaches occur due to the inconstant depositional processes of the sea state. From the granulometric parameters and beach measurements the results showed that the variations in the size of the sand strip of the beaches occur due to the inconstant depositional processes of the sea state. (Table \u003cspan class=\"InternalRef\"\u003e02\u003c/span\u003e).\u003c/p\u003e\n \u003cp\u003eThe beach arch morphology Arpoador to Leblon shows that the circulation cells to the coastal drift meet the prevailing weather conditions. In this region the coastal currents change their origins from barlamar to sotamar when the angles of action of the waves on the coast are alternated. The coastal dynamics are affected by the depositional events of accumulation and removal of the sands that proportionally alter the size of the beaches. (Taggart \u0026amp; Schwartz 1988).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\n \u003ch2\u003e4.4 Arpoador and Leblon the beaches evolution.\u003c/h2\u003e\n \u003cp\u003eThe beach measurements in historical satellite images (Google Earth) allowed to evaluate the dynamics of the beaches under different sedimentation conditions.\u003c/p\u003e\n \u003cp\u003eThe granulometric parameters distribution and the average values of the width of the beaches are fundamental items to determine the evolution of the depositional processes. From these items it becomes possible to define how these processes act on the morphology reducing or expanding the strip of sand and the size of the beaches. In a specific table presented below shows the data of the beach dimension values in centimetres that allow to evaluate the evolution of the depositional processes by the variation of the width in the Arpoador and Jardim de Alah beaches since the year 2000. The variation in the width of the beaches of Arpoador and Leblon (Jardim de Alah) is shown in Table \u003cspan class=\"InternalRef\"\u003e02\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 02\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003e\u0026ndash; The depositional events and width of the beaches since the year 2000.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"7\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eYear observation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eArpoador beach\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eLeblon beach\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDimension\u003c/p\u003e\n \u003cp\u003eBeach width\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eVariation\u003c/p\u003e\n \u003cp\u003e(38.99)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDeposition (D)\u003c/p\u003e\n \u003cp\u003eErosion (E)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDimension\u003c/p\u003e\n \u003cp\u003eBeach width\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eVariation\u003c/p\u003e\n \u003cp\u003e(108.07)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDeposition (D)\u003c/p\u003e\n \u003cp\u003eErosion (E)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e21,04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17,65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e125,72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-17,95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e54,46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-3,6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e104,47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15,47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2003\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e59,97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-10,02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e98,05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20,98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e29,05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e108,89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-9,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e31,39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-4,74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e103,33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-7,6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e48,34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e108,73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9,35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52,66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5,7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e102,37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13,67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2008\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e25,03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e109,01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-13,96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2009\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e22,52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1,72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e106,35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-16,47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2010\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e33,13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1,19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e106,88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5,86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2011\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e18,01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15,74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e123,81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-20,98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2012\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e29,93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e110,93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-9,06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2013\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e56,72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e108,13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17,73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e63,54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-11,76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e96,31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24,55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMean-\u0026gt;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e38,99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-------\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e108,07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--------\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eThe Fig. \u003cspan class=\"InternalRef\"\u003e06\u003c/span\u003e shows the values recorded for the variation in the size of the beaches. It reflects tthe depositional dynamics events on the Arpoador and Jardim de Alah beaches since the year 2000 until 2014. It is possible to verify and relate sedimentation events (erosion or deposition) to the accumulation or removal of sediments on these beaches.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n \u003ch2\u003e4.5 Monthly width variation of the beaches.\u003c/h2\u003e\n \u003cp\u003eMonthly satellite beach width measurements were made during hangover times are listed in Table \u003cspan class=\"InternalRef\"\u003e03\u003c/span\u003e. This result defines how depositional processes act in periods of greater marine agitation in the reduction or expansion of beaches (Christopher and Andrew,2020). Surf events accumulate sand and widen the area in front of the Jardim de Alah channel while reducing the strip of sand on Arpoador beach by erosion (Anex 1).\u003c/p\u003e\n \u003cp\u003eThe storm events accumulate sand at the entrance of the channel that connects the Rodrigo de Freitas lagoon to the sea, resulting in the widening of the sand strip in the front area of the beach of the Jardim de Alah channel. This is a situation that requires constant work by dredgers to free the channel for drainage and renewal of the lagoon waters.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 03\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eHangover season beach width variation (Arpoador 1 / Leblon 2)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eYear\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003emonth\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eArpoador\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003evalue 1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAlah\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003evalue 2\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e40,01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5,79727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e95,01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-3,66727\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e42,95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-2,85727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e105,21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6,53273\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e40,07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5,73727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e106,58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7,90273\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e54,27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8,46273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e97,63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1,04727\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e49,63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3,82273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e110,96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12,28273\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e41,34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-4,46727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e105,21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6,53273\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2008\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e40,31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5,49727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e95,54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-3,13727\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2009\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e46,66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0,85273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e83,57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-15,1073\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2009\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e38,55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-7,25727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e104,85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6,17273\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2009\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e58,58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12,77273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e104,88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6,20273\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2010\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e51,51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5,70273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e76,01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-22,6673\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e45,80727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e98,67727\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eThe results of the measurements are shown in Fig.\u0026nbsp;08. These are values of the mean values variations of the beaches size of Arpoador and Jardim de Allah. They reflect the depositional processes. It is possible to verify the times of greater intensity of the hangovers when the morphology of the beaches is more altered. May is the month in which the depositional processes are most evident. Erosive processes occur with greater frequency and intensity in two periods: May to June and August to September are periods of the greatest change in the beach\u0026rsquo;s morphology.\u003c/p\u003e\n \u003cp\u003eIn Fig. \u003cspan class=\"InternalRef\"\u003e07\u003c/span\u003e it is possible to verify which months were of greater occurrence of hangovers and from the average values for each of the two researched beaches verify the months in which the width of the sand strips on the beaches of Arpoador and Jardim de Alah was affected between 2004 and 2010. It is interesting to note that in some years hangovers have occurred more than once.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"5. CONCLUSIONS / RECOMMENDATIONS","content":"\u003cp\u003eThe results of this work have demonstrated evident relationships between sedimentation processes and coastal morphology (Bertalanffy, 1968; Bennett and Chorley, 1978; Phillips, 1992). Morphological knowledge of coastal environments should include continuous monitoring of depositional processes, considering that these processes can be rapidly altered by natural and anthropogenic causes.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Records of variations in beach width and grain size confirm the erosive events and the morphological changes of the beaches. Especially when large oceanic waves occur in periods of sea hangover. In the area of study, morphological dynamics show that depositional processes always act continuously (Taggart \u0026amp; Schwartz,1988). The depositional processes act at the same time to remove or accumulate sands at different points of the same beach arch. In times of hangovers the sands accumulate, and the strip sand of the beach widens in the front of the channel of the Garden of Alah. At critical hangover moments the sea-lagoon channel connection is closed preventing the renewal of the waters of the Rodrigo de Freitas Lagoon with the sea. The bigger hangovers are the periods of big changes in the morphology of the beaches. The hangover times recorded in the Figure 8 showed that the month of May, in the autumn season is when the marine agitation acts on the beaches with greater intensity.\u003c/p\u003e\n\u003cp\u003eThe results obtained demonstrate that the evolution of beach morphology presents unique aspects in relation to depositional processes with beach segments that respond differently to storm waves in hangover seasons.\u003c/p\u003e\n\u003cp\u003eThe annex 1 shows the figures of simultaneous images of the beaches of Arpoador and Jardim de Alah in times of hangover. They depict how the size of these beaches has their sandy strips altered by depositional processes with the different sedimentation conditions that occur at the same time. The sedimentary dynamics present distinct depositional patterns for the two main beaches along the Arpoador – Leblon beach arch.\u003c/p\u003e\n\u003cp\u003e• - In the area of Arpoador beach the strip of sand is reduced and almost disappears putting constructions of the waterfront in danger.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e• - In the area of Jardim de Alah, the accumulation of sediments expands the sandy strip and begins to obstruct the channel connecting the sea with the Rodrigo de Freitas Lagoon, requiring dredging and removal of sand.\u003c/p\u003e\n\u003cp\u003eConsidering that the indicators of morphodynamics processes had been demonstrate significant variations in beach forms, it is recommended that urban beaches be monitored more frequently. Especially in hangovers times, when the depositional processes are more intense (Annex 2). Meteorological and Oceanographic factors along with anthropic actions affect the depositional processes on the coast. It is recommended that projects focus on maintenance and preservation of beaches including as a priority an approach that balances an engineering perspective with the purely geological perspective (komar, 1976).\u003c/p\u003e\n\u003cp\u003eIn the study área the knowledge of coastal morphodynamics evolution is fundamental to protect beaches from extreme depositional events mainly in relation to the:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eknow the physical factors make more easily the knowledge of the depositional processes that act on the stability of the littoral contours..\u0026nbsp;\u003c/li\u003e\n \u003cli\u003ebeach features that should be carried out more often mainly by the climatic rigors that affect with greater intensity engineering works and coastal depositional processes.\u003c/li\u003e\n \u003cli\u003eextreme events such as those of 2008 on Arpoador beach. In addition to reducing the strip of sand by intense waves, this event hit the sidewalk and caused material damage to the residents and frequenters of that beach,\u003c/li\u003e\n \u003cli\u003edepositional processes are part of the coastal dynamics to restore the morphology of the beaches to the new features after hangover events, works or anthropic actions of fattening (Leblon beach),\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eIn view of the above, it is recommended that the coastal forms defined by the positioning of the coastline, whenever possible, should be characterized in the light of oceanographic conditions at different times of the year and in function:\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;- sedimentation processes,\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;- physical factors, and\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;- of anthropic actions\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn this way, a new concept of ban coastline is admitted, integrating sustainable methods of coastal protection and development of cities,\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNew challenges and opportunities arise to create ways of protecting coastal spaces in urban environments,\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMaintaining public spaces and leisure areas implies a more qualitative and integrated relationship with the waters and with the changing coastal dynamics,\u003c/p\u003e\n\u003cp\u003eThe success of water resources management depends on the continuous monitoring of physical factors. The uncertainty of climate change and the disorderly occupation trends of urban coastal areas require us to seek more efficient methods of control and prevention to mitigate the adversities that are increasingly intense in coastal urban environments.\u003c/p\u003e\n\u003cp\u003eThe application and use of the concepts developed through the study of beach morphodynamics can be efficient in solving problems related to sandy beaches. \u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eIt is concluded that in the study beaches the sediment samples fall mainly in the field of medium sand to fine sand, which indicates a moderate wave action along the shoreline of these areas.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eRECOMMENDS\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFrom the results obtained in this work it is possible to recommend guidelines to mitigate issues of the management of urban beaches. The study of beach morphology should consider variations in beach size by monitoring based on the following items:\u003c/p\u003e\n\u003col start=\"1\" type=\"1\"\u003e\n \u003cli\u003ePhysical factors affecting the sedimentary balance and stability of coastal contours,\u003c/li\u003e\n \u003cli\u003eOceanographic factors by variations in wave energy over time that affects seasonally eroding and silting the shoreline,\u003c/li\u003e\n \u003cli\u003eEnvironmental factors such as the anthropic presence that in tourist areas that can alter the coastal depositional processes,\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAgenor was the main authorF\u0026aacute;bio Ferreira Dias, reviewer of the article and contributor of changesCamille and Ruan were responsible for mapping the area on the GIS\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eChristopher, J. Hein, Andrew, D. Ashton. 2020. Morfodin\u0026acirc;mica da Praia de Areia,\u003c/li\u003e\n \u003cli\u003eBennett \u0026amp; Chorley. \u0026nbsp;1978, Environmental systems: philosophy, analysis and control, London: Methuen, 624pp.\u003c/li\u003e\n \u003cli\u003eBertalanffy, L 1968, General systems theory: foudations developments applications, London: Allen Lane Peguin Press, 311 pp,\u003c/li\u003e\n \u003cli\u003eBird., E.C.F. \u0026nbsp;1996, Beach Management. New York: John Wiley \u0026amp; Sons.\u003c/li\u003e\n \u003cli\u003eCalliari, L. .1. \u0026amp; Klein. A. F. H. 1993, Caracter\u0026iacute;sticas morfodin\u0026acirc;micas e sedimentol\u0026oacute;gicas das praias oce\u0026acirc;nicas entre Rio Grande e Chu\u0026iacute;, RS. Pesquisas. 20 \u0026nbsp;1):48-56\u003c/li\u003e\n \u003cli\u003eEsteves LS, Toldo Jr. EE, Dillenburg SR and Toma-zelli LJ. 2002. Long- and Short-Term Coastal Ero-sion in Southern Brazil. J Coast Res SI 36: 273-282\u003c/li\u003e\n \u003cli\u003eFolk, R.L. \u0026amp; Ward. 1957, Brazos River Bar, A study in the significance of grain size parameters. Journal of sediment petrology.\u003c/li\u003e\n \u003cli\u003eFox, W.T. \u0026amp; Davis, R.A. 1974, Simulation model for storm cycles and beach erosi of America Bulletin.on on Lake Michigan. Geological Society\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eHoefel, F. G. 1998, Morfodin\u0026acirc;mica de Praias Arenosas: uma Revis\u0026atilde;o Bibliogr\u0026aacute;fica. Itaja\u0026iacute;: Univali.\u003c/li\u003e\n \u003cli\u003eKomar, P. D. 1976, Beach processes and sedimentation. Prentice-Hall Inc. New Jersey \u0026ndash; EUA. 428 p.\u003c/li\u003e\n \u003cli\u003eLeinz Viktor. 1969, Geologia Geral. Cia Editora Nacional. SP.\u003c/li\u003e\n \u003cli\u003eLima SF, Almeida LESB and Toldo Jr. EE. 2001.Estimativa da capacidade do transporte longitudinal de sedimentos a partir de dados de ondas para a costado Rio Grande do Sul. Pesquisas em Geoci\u0026ecirc;ncias 28:99-107\u003c/li\u003e\n \u003cli\u003eLins-de-Barros, F.M. 2010, Contribui\u0026ccedil;\u0026atilde;o metodol\u0026oacute;gica para an\u0026aacute;lise local da vulnerabilidade costeira e riscos associados: estudo de caso da Regi\u0026atilde;o dos Lagos, Rio de Janeiro. Tese doutorado, UFRJ, p297.\u003c/li\u003e\n \u003cli\u003eLuque, P., G\u0026oacute;mez-Pujol, L., Ribas, F. \u003cem\u003eet al.\u003c/em\u003e\u0026nbsp; 2023, Shoreline response to sea-level rise according to equilibrium beach profiles. \u003cem\u003eSci Rep\u003c/em\u003e\u003cstrong\u003e13\u003c/strong\u003e, 15789 (2023). https://doi.org/10.1038/s41598-023-42672-3\u003c/li\u003e\n \u003cli\u003eMuehe, D. \u0026amp; D\u0026ouml;bereiner, C. 1977, Din\u0026acirc;mica do fundo marinho ao longo do pier de Ipanema, Rio de Janeiro. An. Acad. Bras. Ci\u0026ecirc;nc, 49(2):281-286.\u003c/li\u003e\n \u003cli\u003eMuehe, D. 1979, Sedimentology and topography of ahigh energy coastal environment between Rio de Janeiro and Cabo Frio, Brazil. An. Acad. Bras.Cienc. ,51(3):473-481.\u003c/li\u003e\n \u003cli\u003eMuehe, D. 2001, Crit\u0026eacute;rios Morfodin\u0026acirc;micos para o Estabelecimento de Limites da Orla Costeira para fins de Gerenciamento. Revista Brasileira de Geomorfologia,Volume 2, N\u0026ordm; 1.\u003c/li\u003e\n \u003cli\u003eParente, C. E. 1999, \u003cem\u003eUma nova t\u0026eacute;cnica espectral para an\u0026aacute;lise direcional de ondas\u003c/em\u003e. Mar\u0026ccedil;o 1999. Tese (Doutorado em F\u0026iacute;sica) - Universidade Federal do Rio de Janeiro, Rio de Janeiro\u003c/li\u003e\n \u003cli\u003ePhillips, J.D. 1992, Nonlinear dynamical systems in geomorphology: revolution or Evolution, Geomorphology, 5, 219-29,01\u003c/li\u003e\n \u003cli\u003eShepard, F. P. 1950, Beach cycles in Southern California. Beach Erosion board. Technical Memorandum, n. 20, 1950, 26p.\u003c/li\u003e\n \u003cli\u003eShort, 1979. Three dimensional beach stage model. Journal of Geology.\u003c/li\u003e\n \u003cli\u003eShort, A. D., 1999. \u0026nbsp;Beaches. in \u003cem\u003eHandbook of Beach and Shoreface Morphodynamics\u003c/em\u003e (ed Short, A. D.), 3\u0026ndash;20 (John Wiley \u0026amp; Sons, Great Britain, 1999)\u003c/li\u003e\n \u003cli\u003eSilva, A.C. 1985, Sedimenta\u0026ccedil;\u0026atilde;o e morfologia do fundo da plataforma continental interna nas proximidades da Ilha do Cabo Frio, RJ. Disserta\u0026ccedil;\u0026atilde;o (Mestrado em Geografia) \u0026ndash; IGEO, UFRJ, Rio de Janeiro. 189 p.\u003c/li\u003e\n \u003cli\u003eSilva, A.C. 2009,\u0026nbsp;Din\u0026acirc;mica Batim\u0026eacute;trica e Sedimentol\u0026oacute;gica da Regi\u0026atilde;o do Cabo Frio \u0026ndash; Estado do Rio de Janeiro. Tese: Dotourado em Geologia : UFRJ / IGEO, 2009 21, 154 p.: il.; 30cm\u003c/li\u003e\n \u003cli\u003eSouza, C.R.G. 2007, Determination of net shore-drift cells based on textural and morfological gradations along foeshore sandy beaches. Journal of Coastal Research.\u003c/li\u003e\n \u003cli\u003eSUGUIO, Kenitiro. 2010, Geologia sedimentar do Quatern\u0026aacute;rio e mudan\u0026ccedil;as ambientais. S\u0026atilde;o Paulo: Ofi cina de Textos.\u003c/li\u003e\n \u003cli\u003eSunamara, T. 1988, Beach morphologies and their changr. In: Horikawa, K. (ed). Nearshore dynamics and Coastal Processes. [S.J.]: University of Tokoyo.\u003c/li\u003e\n \u003cli\u003eTaggaart, B.E. Schwartz, M. L 1988, Net shore drift direction determination: a systematic approach. Journal of shoreline management, 3(4), 285-309.\u003c/li\u003e\n \u003cli\u003eToldo, E. E.; Dillenburg, S. R.; Almeida, L. E. S. B.; Tabajara, L. L.; Martins, R. \u0026amp; Cunha, L. O. B. P. 1993,. Par\u0026acirc;metros morfom\u0026eacute;tricos da Praia de Imb\u0026eacute;, RS. Pesquisas, 20(1):27-32.\u003c/li\u003e\n \u003cli\u003eToldo Jr. EE, Almeida LES, Barros C e MartinsLR. 1999. Retiro do Litoral do Rio Grande do SulZona, Brasil. Em: Martins LR e Santana CI(Ed.), Recursos N\u0026atilde;o Vivos do Sul do Brasil-Zona Costeira e Margem Continental. Porto Alegre, Brasil: Editora da UFRGS, p.62-68.\u003c/li\u003e\n \u003cli\u003eTorres JR, A. R. 1995, Resposta da Ressurg\u0026ecirc;ncia Costeira de Cabo Frio a For\u0026ccedil;antes Locais. Disserta\u0026ccedil;\u0026atilde;o de Mestrado apresentada \u0026agrave; COPPE/UFRJ.\u003c/li\u003e\n \u003cli\u003eWentworth, C.K. 1922, A Scale of Grade and Class terms for clastic sediments, Journal of Geology, 30:377-392 p.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eWright, L D. \u0026amp; Short, A.D. 1984, Morphodynamic variability of surf zones and beaches: a synthesis. Marine Geology, 56, 93-11\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-4713442/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4713442/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis article deals with morphodynamics and sedimentation on urban sandy beaches. It focuses on the relationship between depositional dynamics on the beaches of Arpoador, Ipanema and Leblon, in the south zone of the city of Rio de Janeiro, Brazil. The coast morphological evolution described here is a function of sedimentation processes and the width variation on the beaches sand strip. Sediments are evaluated from eighteen beach samples collected from six transect beach profiles to verify the predominant sediment types. Coastal morphodynamics is described based on depositional processes on the morphological beach’s evolution. The morphology evolution is depicted from historical satellite images. Meteorological and oceanographic data reflect the depositional dynamics of beaches under different climatic conditions. Granulometric analysis is used here to determine the grain size, standard deviation, skewness values, and kurtosis. The areas of erosion and deposition of the beaches are shown by maps with the points most susceptible to the negative effects of storms and climate change. The depositional dynamics that occur at the same time alternately between the studied beaches is also analysed to improve the understanding of the depositional processes. On some occasions, the reduction of sand on Arpoador beach occurs at the same time as the accumulation of sand in the area in front of Jardim de Alah beach. On some occasions, the channel connecting the Rodrigo de Freitas Lagoon with the sea is closed. It is hoped that a better understanding of the depositional processes discussed here can be used to facilitate the management and preservation of urban beaches.\u003c/p\u003e","manuscriptTitle":"Morphodynamics Evolution of the Urban Beaches of Rio de Janeiro, Brazil city.","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-10 12:04:53","doi":"10.21203/rs.3.rs-4713442/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2b0bbfae-f4b9-4145-a639-a286b670c954","owner":[],"postedDate":"August 10th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-08-18T11:10:48+00:00","versionOfRecord":[],"versionCreatedAt":"2024-08-10 12:04:53","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4713442","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4713442","identity":"rs-4713442","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}