scholarly journals The impact of sea-level rise on tidal characteristics around Australasia

2018 ◽  
Author(s):  
Alexander Harker ◽  
J. A. Mattias Green ◽  
Michael Schindelegger
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Tidal Dissipation ◽  
North West ◽  
The North ◽  
Arafura Sea ◽  
Coastal Features ◽  
Tidal Characteristics ◽  
Shelf Region ◽  
The Impact

Abstract. An established tidal model, validated for present-day conditions, is used to investigate the effect of large levels of sea-level rise (SLR) on tidal characteristics around Australasia. SLR is implemented through a uniform depth increase across the model domain, with a comparison between the coastal boundary being treated as impenetrable or allowing low-lying land to flood. The complex spatial response of the semi-diurnal constituents, M2 and S2, is broadly similar, with the magnitude of M2's response being greater. The most predominant features of this response are large amplitude changes in the Arafura Sea and within embayments along Australia's north-west coast, and the generation of new amphidromic systems within the Gulf of Carpentaria and south of Papua, once water depth across the domain is increased by 3 and 7 m respectively. Dissipation from M2 increases around the islands in the north of the Sahul shelf region and around coastal features along north Australia, leading to a notable drop in dissipation along Eighty Mile Beach. The diurnal constituent, K1, is found to be amplified within the Gulf of Carpentaria, indicating a possible change of resonance properties of the gulf. Coastal flooding has a profound impact on the response of tidal amplitudes to SLR, particularly K1, by creating local regions of increased tidal dissipation and altering the shape of coastlines.

scholarly journals The impact of sea-level rise on tidal characteristics around Australia

Ocean Science ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 147-159 ◽  
Author(s):  
Alexander Harker ◽  
J. A. Mattias Green ◽  
Michael Schindelegger ◽  
Sophie-Berenice Wilmes
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Open Boundary ◽  
Open Boundary Conditions ◽  
Tidal Dissipation ◽  
North West ◽  
The North ◽  
Tidal Changes ◽  
Tidal Characteristics ◽  
The Impact

Abstract. An established tidal model, validated for present-day conditions, is used to investigate the effect of large levels of sea-level rise (SLR) on tidal characteristics around Australasia. SLR is implemented through a uniform depth increase across the model domain, with a comparison between the implementation of coastal defences or allowing low-lying land to flood. The complex spatial response of the semi-diurnal M2 constituent does not appear to be linear with the imposed SLR. The most predominant features of this response are the generation of new amphidromic systems within the Gulf of Carpentaria and large-amplitude changes in the Arafura Sea, to the north of Australia, and within embayments along Australia's north-west coast. Dissipation from M2 notably decreases along north-west Australia but is enhanced around New Zealand and the island chains to the north. The diurnal constituent, K1, is found to decrease in amplitude in the Gulf of Carpentaria when flooding is allowed. Coastal flooding has a profound impact on the response of tidal amplitudes to SLR by creating local regions of increased tidal dissipation and altering the coastal topography. Our results also highlight the necessity for regional models to use correct open boundary conditions reflecting the global tidal changes in response to SLR.

scholarly journals The significance of coastal bathymetry representation for modelling the tidal response to mean sea level rise in the German Bight

Ocean Science ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 31-44 ◽  
Author(s):  
Caroline Rasquin ◽  
Rita Seiffert ◽  
Benno Wachler ◽  
Norbert Winkel
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
North Sea ◽  
German Bight ◽  
Coastal Areas ◽  
Tidal Dynamics ◽  
Mean Sea Level ◽  
The North ◽  
The North Sea ◽  
The Impact

Abstract. Due to climate change an accelerated mean sea level rise is expected. One key question for the development of adaptation measures is how mean sea level rise affects tidal dynamics in shelf seas such as the North Sea. Owing to its low-lying coastal areas, the German Bight (located in the southeast of the North Sea) will be especially affected. Numerical hydrodynamic models help to understand how mean sea level rise changes tidal dynamics. Models cannot adequately represent all processes in overall detail. One limiting factor is the resolution of the model grid. In this study we investigate which role the representation of the coastal bathymetry plays when analysing the response of tidal dynamics to mean sea level rise. Using a shelf model including the whole North Sea and a high-resolution hydrodynamic model of the German Bight we investigate the changes in M2 amplitude due to a mean sea level rise of 0.8 and 10 m. The shelf model and the German Bight Model react in different ways. In the simulations with a mean sea level rise of 0.8 m the M2 amplitude in the shelf model generally increases in the region of the German Bight. In contrast, the M2 amplitude in the German Bight Model increases only in some coastal areas and decreases in the northern part of the German Bight. In the simulations with a mean sea level rise of 10 m the M2 amplitude increases in both models with largely similar spatial patterns. In two case studies we adjust the German Bight Model in order to more closely resemble the shelf model. We find that a different resolution of the bathymetry results in different energy dissipation changes in response to mean sea level rise. Our results show that the resolution of the bathymetry especially in flat intertidal areas plays a crucial role for modelling the impact of mean sea level rise.

The Impact of Sea Level Rise on Maritime Limits: A Grotian Moment in the Law of the Sea?

Grotiana ◽  
2021 ◽  
Vol 42 (2) ◽  
pp. 277-303
Author(s):  
Snjólaug Árnadóttir
Keyword(s):  
International Law ◽  
Sea Level Rise ◽  
Sea Level ◽  
Paradigm Shift ◽  
Legal Order ◽  
Law Of The Sea ◽  
National Jurisdiction ◽  
The Law ◽  
Coastal Features ◽  
The Impact

Abstract The legal order of the oceans centres on coastal geography which is undergoing unprecedented changes. Claims to national jurisdiction are based on distance from the coast and are only enforceable as long as they are consistent with international law. Consequently, sea level rise and submergence of coastal features can affect the location and enforceability of unilateral maritime limits and bilateral boundaries. Some States wish to maintain previously established entitlements around submerged territory but the only way to prevent fluctuations of unilateral limits is through artificial conservation of coastlines. Therefore, a change, in either the location of maritime entitlements or rules governing such entitlements, is inevitable. It has been proposed that maritime limits should be frozen to ensure opposability as coastlines change. That would enable States to exercise sovereignty and sovereign rights over areas that have no anchor in coastal territory, arguably causing a departure from the land dominates the sea principle and a Grotian Moment in the law of the sea. However, this article concludes that it is unlikely that proposals to freeze maritime limits will change the law of the sea and that the proposals may in fact serve to deter another paradigm shift, one that involves a departure from the principle of stable boundaries.

scholarly journals Exceptional retreat of Novaya Zemlya's marine-terminating outlet glaciers between 2000 and 2013

2017 ◽  
Vol 11 (5) ◽  
pp. 2149-2174 ◽  
Author(s):  
J. Rachel Carr ◽  
Heather Bell ◽  
Rebecca Killick ◽  
Tom Holt
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Atlantic Multidecadal Oscillation ◽  
Glacier Retreat ◽  
Remotely Sensed Data ◽  
Novaya Zemlya ◽  
The North ◽  
Air Temperatures ◽  
The North Atlantic Oscillation ◽  
The Impact

Abstract. Novaya Zemlya (NVZ) has experienced rapid ice loss and accelerated marine-terminating glacier retreat during the past 2 decades. However, it is unknown whether this retreat is exceptional longer term and/or whether it has persisted since 2010. Investigating this is vital, as dynamic thinning may contribute substantially to ice loss from NVZ, but is not currently included in sea level rise predictions. Here, we use remotely sensed data to assess controls on NVZ glacier retreat between 1973/76 and 2015. Glaciers that terminate into lakes or the ocean receded 3.5 times faster than those that terminate on land. Between 2000 and 2013, retreat rates were significantly higher on marine-terminating outlet glaciers than during the previous 27 years, and we observe widespread slowdown in retreat, and even advance, between 2013 and 2015. There were some common patterns in the timing of glacier retreat, but the magnitude varied between individual glaciers. Rapid retreat between 2000 and 2013 corresponds to a period of significantly warmer air temperatures and reduced sea ice concentrations, and to changes in the North Atlantic Oscillation (NAO) and Atlantic Multidecadal Oscillation (AMO). We need to assess the impact of this accelerated retreat on dynamic ice losses from NVZ to accurately quantify its future sea level rise contribution.

scholarly journals Wind-induced sea level fluctuations at Yuzhnyi and Chornomorsk sea ports and evaluation of the possibility of their forecast

2018 ◽  
pp. 100-106
Author(s):  
R. V. Gavrilyuk ◽  
N. M. Yuvchenko
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Black Sea ◽  
Coastal Area ◽  
The Black Sea ◽  
The South ◽  
North West ◽  
The North ◽  
Wind Characteristics ◽  
Sea Ports

The sea level of the Black Sea coastal area is subject to non-periodic wind-induced fluctuations. Such fluctuations affect economic activity of the sea ports, enterprises and businesses located within the coastal area while those may be flooded when the sea level rises and, on the contrary, there is a threat of vessels grounding in case of sea level fall. There are several big sea ports which are located at the north-western part of the Black Sea and affected by wind-induced fluctuations. Therefore, the study of these processes and development of methods allowing their forecast are of great practical interest and this fact proves the topicality of the conducted research. The article's aim is to analyse wind-induced fluctuations within the water area of Yuzhnyi and Chornomorsk sea ports, identify statistical links between such fluctuations and wind characteristics / equations used for calculation of their values. The observations at Chornomorsk (2006-2013) and Yuzhnyi (2000-2011) stations show that within a year there are 1-2 upsurge-downsurge occurrences during an average month, however, the number of those increases up to 3-4 over the autumn-winter period. The average sea level rise at Chornomorsk station is equal to 34 cm, the average sea level fall – 38 cm, maximum values amount to 97 cm and 191 cm, respectively. The average sea level rise at Yuzhnyi station is equal to 30 cm, the average sea level fall – 34 cm, maximum values amount to 91 and 98 cm, respectively. The average duration of wind-induced fluctuations at both stations amount to 34-38 hours. In most cases the sea level rise is observed at Chornomosk station when winds blow from the South and the South-East, at Yuzhnyi station  – when those blow from the South, the South-East and the South-West. The sea level fall is observed at Chornomosk station when winds blow from the North-West and the West, at Yuzhnyi station – when those blow from the North, the North-West and the North-East. Both stations are characterized with effective directions of wind causing occurrence of upsurge-downsurges. Based on the regression analysis equations for calculation of the sea level rise and fall values associated with wind characteristics were defined. The initial value of the sea level and the sum of the wind projections on effective directions for previous 30 hours are used as arguments in the equations. The accuracy of equation-based calculation constitutes 60-90%. The article offers recommendations on the use of equations when forecasting wind-induced fluctuations.

scholarly journals The significance of coastal bathymetry representation for modelling the tidal response to mean sea level rise in the German Bight

2019 ◽  
Author(s):  
Caroline Rasquin ◽  
Rita Seiffert ◽  
Benno Wachler ◽  
Norbert Winkel
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
North Sea ◽  
German Bight ◽  
Coastal Areas ◽  
Tidal Dynamics ◽  
Mean Sea Level ◽  
The North ◽  
The North Sea ◽  
The Impact

Abstract. Due to climate change an accelerated mean sea level rise is expected. One key question for the development of adaptation measures is how mean sea level rise affects tidal dynamics in shelf seas such as the North Sea. Owing to its flat coastal areas, especially the German Bight (located in the south-east of the North Sea) will be affected. Numerical hydrodynamic models help to understand how mean sea level rise changes tidal dynamics. By definition models cannot represent all processes in overall detail. One limiting factor is the resolution of the model grid. In this study we investigate which role the representation of the coastal bathymetry plays when analysing the response of tidal dynamics to mean sea level rise. Using a shelf model including the whole North Sea and a high-resolution hydrodynamic model of the German Bight we investigate the changes in M2 amplitude due to a mean sea level rise of 0.8 m and 10 m. To the mean sea level rise of 0.8 m the shelf model and the German Bight Model react in different ways. In the shelf model the M2 amplitude generally increases in the region of the German Bight. In contrast, the M2 amplitude in the German Bight Model increases only in some coastal areas and decreases in the northern part of the German Bight. In two case studies we adjust the German Bight Model in order to more closely resemble the shelf model. We find that a different resolution of the bathymetry results in different energy dissipation changes in response to mean sea level rise. Our results show that the resolution of the bathymetry especially in flat intertidal areas plays a crucial role for modelling the impact of mean sea level rise in the order of 1 m. For higher mean sea level rise scenarios (10 m) the resolution of the bathymetry is less important.

Sign in / Sign up

Export Citation Format

Share Document