ON SEA LEVEL ALONG THE BRAZILIAN COAST

ABSTRACT. This is Part II of a contribution on Brazilian sea levels – Part I dealt with the seasonal variability. It examines the sea level changes along the Brazilian coast from series with less than 40 years of measurement, against the background of changes in series of all continents and islands around the world, considering data distributed by the Permanent Service for Mean Sea Level (PSMSL). The method of analysis follows the display of the data in a: 1) ﬁrst plot of relative sea level trends (C), against the length of the series (L) expressed in years and a: 2) second plot showing the relative sea level regression coefﬁcients (C), versus the corresponding correlation values (m). The ﬁrst plot of all PSMSL data exhibited a cusped like shape of the distribution of (C), having maxima values about 10-20 cm/cty for the longest series (120-137 years), indicating the overall positive value of the global relative sea level trend. Similar ﬁrst plot, a regional plot of African and South American data adjusted to the same global relative mean level, showed that the Brazilian trends (C), are mostly concentrated in the positive side of the cusped: (ports of Bel´em, Fortaleza. Recife, Canavieiras, Salvador, Ilha Fiscal, Rio de Janeiro, Ubatuba, Cananeia, and Imbituba) which have a mean value within 30 to 40 cm/cty. The second plot, with all set of PSMSL data, was necessary in order to display trend values of non simultaneous series of different continental borders and lengths in the same bin. The plot gave two different linear inclinations for trend values within ± 0.3 cm/y, in the positive and negative sides of the ﬁgure. The global ratio obtained for the trends was R = − 1.2, suggesting also, from the linearity of the plot, that the trends and correlation values are statistically dependent variables. The graph produced a different value for global balance of the value C obtained in the ﬁrst plot. Similar regional second plot of the African Atlantic and South American borders, which include the Brazilian data, also gave rise to two new regression lines with trend C*1 < 0 and C*2 > 0, with a ratio R = − 2.2, involving bins of m and C values that are also null in the vicinity of zero. This regionally plot conﬁrmed the result of the second plot with PSMSL series that they (C and m), globally, should be dependent statistical variables. These ﬁndings, however, do not change the fact that the regional series with trends 0.2 cm/year have correlation values m < 0.3, whatever their lengths, and that the mean value of the relative sea level, along the Brazilian coast, is increasing with an estimated rate of 30 to 40 cm/cty. Further work is under way, aiming at solving the above apparently contradictory results.Keywords: sea level, Brazilian coast, PSMSL series, global relative sea level, imbalance of relative sea level. RESUMO. Esta é a segunda parte de uma contribuição sobre os níveis do mar na costa brasileira – a parte I tratou da variação sazonal – ela examina as mudanças do nível do mar ao longo da costa brasileira a partir de séries com comprimentos menores do que 40 anos contra as variações das séries de todas as ilhas e continentes do globo, levando em conta as séries distribuídas pelo Permanent Service for the Mean Sea Level (PSMSL). A descrição é feita através da exposição dos dados em 1) um gráﬁco das tendências (C) contra o comprimento das séries (L) em dados anuais e um 2) segundo gráﬁco mostrando as tendências dos níveis relativos (C) contra os valores dos valores das correlações (m) entre as séries e os dados da sua reta de regressão. O primeiro gráﬁco com as séries do PSMSL mostrou uma forma de cúspide como distribuição de (C) com valores máximos de cerca de 10-20 cm/século para as séries mais compridas (120-137 anos). Figura semelhante com dados da América do Sul e da África ajustada para essa média, mostra o mesmo padrão (portos de Belém, Fortaleza, Canavieiras, Salvador, Ilha Fiscal, Rio de Janeiro, Ubatuba, Cananeia e Imbituba). O segundo gráﬁco foi necessário para a análise de séries com comprimentos diversos e não simultâneas como as séries do PSMSL, produziu duas novas retas com inclinações C*1 < 0 e C* > 0 construídas a partir dos valores das tendências C das séries PSMSL, com inclinações dentro da faixa de 0,2 cm/ano na parte positiva e negativa da ﬁgura, sugerindo uma não equivalência entre essas inclinações, em favor de valor global negativo de C* para o Nível Relativo do Mar. Figura semelhante produzida com as s´eries Africanas e Sul Americanas, que incluíram as séries brasileiras, mostrou característica similar, além de indicar que séries com tendências ± 0,2 cm/ano têm valores de correlação m < 0,3 qualquer que seja o comprimento da série. Os resultados interessantes, mas contraditórios, que incluem a dependência linear global entre correlação e tendências das séries fornecidas pelo PSMSL, devem ser analisados em continuação aos presentes estudos, que indicam que o nível relativo do mar na costa brasileira está aumentando à razão de 30 a 40 cm/século.Palavras-chave: nível do mar, costa brasileira, séries do PSMSL, nível relativo do mar global, balanço do nível relativo do mar.

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Influence of the "Hypsithermal Age" and "Neoglaciation" climatic conditions on the Brazilian coast.

Pesquisas em Geociências ◽

10.22456/1807-9806.20296 ◽

2001 ◽

Vol 28 (2) ◽

pp. 213 ◽

Cited By ~ 2

Author(s):

KENITIRO SUGUIO

Keyword(s):

United States ◽

Gulf Of Mexico ◽

Sea Level ◽

Southeastern United States ◽

Climatic Conditions ◽

Brazilian Coast ◽

Sea Level Changes ◽

Relative Sea Level ◽

Sea Levels ◽

The Past

Meanwhile the highest relative sea-level is the present one in southeastern United States (Gulf of Mexico) or in Netherlands coast, most of the Brazilian coast exhibited Holocene sea-levels higher than the present in the past. The Brazilian curves, representing the relative sea-level changes during last 7.000 years, are outlined using sedimentological, biological and prehistorical past sea-level records. This paper shows that these relative sea-level records, during the Holocene, can be suitably used to demonstrate the influence of the worldwide known paleoclimatic events, like the “Hypsithermal Age” and “Neoglaciation” on the Brazilian coast.

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Relative sea-level rise during the Main Postglacial Transgression in NE Scotland, U.K.

Transactions of the Royal Society of Edinburgh Earth Sciences ◽

10.1017/s0263593300002480 ◽

1999 ◽

Vol 90 (1) ◽

pp. 1-27 ◽

Cited By ~ 16

Author(s):

D. E. Smith ◽

C. R. Firth ◽

C. L. Brooks ◽

M. Robinson ◽

P. E. F. Collins

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Sea Level Changes ◽

Relative Sea Level ◽

Sea Levels ◽

Relative Sea Level Rise ◽

The Mean ◽

Run Up ◽

Storegga Slide

AbstractFlandrian (Holocene) relative sea level changes in the lower Ythan valley, NE Scotland, U.K., are inferred from detailed stratigraphical evidence including microfossil analysis and radiocarbon assay. The principal event recorded is the Main Postglacial Transgression, which was under way in the area by c. 8300 and had culminated before c. 4000 radiocarbon years BP. It is concluded that the rise in relative sea levels during the transgression in the area exceeded 12 m; that the mean rate of rise there was 8·05 mm a−1 between c. 8300 and c. 7100 radiocarbon years BP, or 7·09 mm a−1 based upon calibrated dates for the same period, before declining markedly to 1·75 mm a−1 (radiocarbon) or 1·86 mm a−1 (calibrated) to the culmination of the event. By comparison with other sites, the culmination appears to have been time-transgressive in eastern Scotland. Deposits of the Second Storegga Slide tsunami, which occurred during the Main Postglacial Transgression, are present in the Ythan valley, where the sediment run-up of the event at the sites studied is estimated to have been within the range 2·99–5·19 m.

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SEA-LEVELS, LATE QUATERNARY | Late Quaternary Relative Sea-Level Changes at Mid-Latitudes

Encyclopedia of Quaternary Science ◽

10.1016/b978-0-444-53643-3.00140-0 ◽

2013 ◽

pp. 489-494 ◽

Cited By ~ 3

Author(s):

A.C. Kemp ◽

B.P. Horton ◽

S.E. Engelhart

Keyword(s):

Sea Level ◽

Late Quaternary ◽

Sea Level Changes ◽

Relative Sea Level ◽

Sea Levels

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Sea-level fluctuations and coastal evolution in the state of Rio de Janeiro, southeastern Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201420140007 ◽

2014 ◽

Vol 86 (2) ◽

pp. 671-683 ◽

Cited By ~ 38

Author(s):

JOÃO WAGNER A. CASTRO ◽

KENITIRO SUGUIO ◽

JOSÉ C.S. SEOANE ◽

ALINE M. DA CUNHA ◽

FABIO F. DIAS

Keyword(s):

Sea Level ◽

Rio De Janeiro ◽

Atlantic Coast ◽

Southeastern Brazil ◽

Brazilian Coast ◽

14C Dating ◽

Relative Sea Level ◽

Coastal Evolution ◽

The Holocene ◽

First Time

The present paper aims to investigate the relative sea-level and the coastal evolution during the Holocene in the Rio de Janeiro coastline, based on geological and biological indicators. Using topographic survey, excavation and coring, and 14C dating of these coastal deposits and beachrocks outcrops, we have reconstructed a sea-level curve for the Holocene. For the first time on the Brazilian coast it was identified a negative record of relative sea-level during Late Pleistocene and Early Holocene transition. After the transition, a relatively rapid increase of sea-level began. At approximately at 8500 cal yr BP, the sea-level was 0.5 m below the current level, was overtaken for the first time in the Holocene, at approximately 7500 cal yr BP. The maximum level of +2.5 m was reached between 4770 and 4490 cal yr BP. At the point of maximum transgression, the sea-level began a general behavior of lowering until the present. These results confirm other data already obtained elsewhere along the Atlantic coast of South America. The results of this study are consistent with previous researches and they help to refine the Holocene sea-level record along the Brazilian coast.

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Recent Sea Level Change in the Black Sea from Satellite Altimetry and Tide Gauge Observations

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi9030185 ◽

2020 ◽

Vol 9 (3) ◽

pp. 185 ◽

Cited By ~ 1

Author(s):

Nevin Avşar ◽

Şenol Kutoğlu

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Black Sea ◽

Satellite Altimetry ◽

Tide Gauge ◽

The Black Sea ◽

Sea Level Changes ◽

Early 19Th Century ◽

Mean Sea Level ◽

The Mean

Global mean sea level has been rising at an increasing rate, especially since the early 19th century in response to ocean thermal expansion and ice sheet melting. The possible consequences of sea level rise pose a significant threat to coastal cities, inhabitants, infrastructure, wetlands, ecosystems, and beaches. Sea level changes are not geographically uniform. This study focuses on present-day sea level changes in the Black Sea using satellite altimetry and tide gauge data. The multi-mission gridded satellite altimetry data from January 1993 to May 2017 indicated a mean rate of sea level rise of 2.5 ± 0.5 mm/year over the entire Black Sea. However, when considering the dominant cycles of the Black Sea level time series, an apparent (significant) variation was seen until 2014, and the rise in the mean sea level has been estimated at about 3.2 ± 0.6 mm/year. Coastal sea level, which was assessed using the available data from 12 tide gauge stations, has generally risen (except for the Bourgas Station). For instance, from the western coast to the southern coast of the Black Sea, in Constantza, Sevastopol, Tuapse, Batumi, Trabzon, Amasra, Sile, and Igneada, the relative rise was 3.02, 1.56, 2.92, 3.52, 2.33, 3.43, 5.03, and 6.94 mm/year, respectively, for varying periods over 1922–2014. The highest and lowest rises in the mean level of the Black Sea were in Poti (7.01 mm/year) and in Varna (1.53 mm/year), respectively. Measurements from six Global Navigation Satellite System (GNSS) stations, which are very close to the tide gauges, also suggest that there were significant vertical land movements at some tide gauge locations. This study confirmed that according to the obtained average annual phase value of sea level observations, seasonal sea level variations in the Black Sea reach their maximum annual amplitude in May–June.

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Relative sea-level changes in crete: reassessment of radiocarbon dates from Sphakia and west Crete

The Annual of the British School at Athens ◽

10.1017/s0068245400017378 ◽

2002 ◽

Vol 97 ◽

pp. 171-200 ◽

Cited By ~ 11

Author(s):

Simon Price ◽

Tom Higham ◽

Lucia Nixon ◽

Jennifer Moody

Keyword(s):

Sea Level ◽

Late Antiquity ◽

Isotopic Fractionation ◽

Sea Level Changes ◽

Relative Sea Level ◽

Radiocarbon Dates ◽

Sea Levels ◽

Catastrophic Earthquake ◽

Radiocarbon Data ◽

Calendar Dates

This article is concerned with the recognition and dating of Holocene relative sea-level changes along the coast of west Crete (an island located in the active Hellenic subduction arc of the southern Aegean) and in particular in Sphakia. Radiocarbon data for changes in sea levels collected and analysed previously must (a) be recorrected to take into account isotopic fractionation, and (b) recalibrated by using the new marine reservoir value. These new radiocarbon dates are analysed using Bayesian statistics. The resulting calendar dates for changes in sea level are younger than previously assumed. In particular the Great Uplift in western Crete in late antiquity must be dated to the fifth or sixth century AD, not to AD 365. Moreover, recent work on tectonics suggests that the Great Uplift need not have been accompanied by a catastrophic earthquake. Finally, we consider the consequences of the Great Uplift for some coastal sites in Sphakia.

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Holocene relative sea levels and coastal changes in the lower Cree valley and estuary, SW Scotland, U.K.

Transactions of the Royal Society of Edinburgh Earth Sciences ◽

10.1017/s0263593300000456 ◽

2002 ◽

Vol 93 (4) ◽

pp. 301-331 ◽

Cited By ~ 13

Author(s):

D. E. Smith ◽

J. M. Wells ◽

T. M. Mighall ◽

R. A. Cullingford ◽

L. K. Holloway ◽

...

Keyword(s):

Sea Level ◽

Early Holocene ◽

Coastal Geomorphology ◽

Sea Level Changes ◽

Relative Sea Level ◽

Sea Levels ◽

Coastal Changes

ABSTRACTChanges in Holocene (Flandrian) relative sea levels and coastal geomorphology in the lower Cree valley and estuary, SW Scotland, are inferred from detailed morphological and stratigraphical investigations. A graph of relative sea level changes is proposed for the area. Rising relative sea levels during the early Holocene were interrupted at c. 8300–8600 14C years B.P.(c. 9400–9900 calibrated years B.P.), when an extensive estuarine surface was reached at c. −1 m O.D., after which a fluctuating rise culminated at c. 6100–6500 14C B.P. (c. 7000–7500 calibrated years B.P.) in a prominent shoreline and associated estuarine surface measured at 7·7–10·3 m O.D. A subsequent fall in relative sea level was followed by a rise to a shoreline at 7·8–10·1 m O.D., exceeding or reoccupying the earlier shoreline over much of the area after c. 5000 14C B.P. (c. 5,800 calibrated years B.P.), before relative sea level fell to a later shoreline, reached after c. 2900 14C B.P. (c. 3100 calibrated years B.P.) at 5·5–8·0 m O.D., following which relative sea levels fell, ultimately reaching present levels. During these changes, a particular feature of the coastline was the development of a number of barrier systems. The relative sea level changes identified are compared with changes elsewhere in SW Scotland and their wider context is briefly considered.

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Sea-level variations on the north and northwest coasts of Spain

ICES Journal of Marine Science ◽

10.1093/icesjms/fss058 ◽

2012 ◽

Vol 69 (5) ◽

pp. 720-727 ◽

Cited By ~ 3

Author(s):

María Jesús García ◽

Elena Tel ◽

Joaquín Molinero

Keyword(s):

Sea Level ◽

North Atlantic ◽

Extreme Values ◽

Mean Sea Level ◽

Sea Levels ◽

The North ◽

Glacial Rebound ◽

Sea Level Variations ◽

The Mean ◽

Range Of Variation

Abstract García, M. J., Tel, E., and Molinero, J. 2012. Sea-level variations on the north and northwest coasts of Spain. – ICES Journal of Marine Science, 69: 720–727. An exhaustive analysis of historical sea-level records at three stations located along the northern and northwestern Spanish coast has permitted a description of the mean sea-level trend over the past 67 years. The analysis also produced results on the type, amplitude, and propagation of tides, as well as on the range of variation in the sea level, extreme values, and return periods. Once corrected for the Post Glacial Rebound, the rise in the mean sea level was estimated at 2.38, 2.45, and 2.65 mm year−1 in Santander, A Coruña, and Vigo, respectively. The meteorological contribution is evaluated by the winter North Atlantic Oscillation index, producing a correlation of −0.658 with the empirical orthogonal function mode 1, which explained 81.86% of the total variance of winter (from December to March) mean sea levels. Harmonic analysis evidenced the semi-diurnal nature of the tide and showed that the amplitude and propagation of the M2 tidal wave followed the North Atlantic regional pattern, with decreasing amplitudes and phases from east to west. Hourly height levels were run through an extreme analysis and resulted in maximum sea-level values over the respective mean sea levels (datum): 2.55, 2.48, and 2.51 m in Santander, A Coruña, and Vigo, respectively. The estimated extreme levels for a 120-year return period exceeded the observed maxima in the three locations by 0.25, 015, and 0.10 m, respectively.

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