Coastal flooding: impact of waves on storm surge during extremes – a case study for the German Bight

Staneva, Joanna; Wahle, Kathrin; Koch, Wolfgang; Behrens, Arno; Fenoglio-Marc, Luciana; Stanev, Emil V.

doi:10.5194/nhess-16-2373-2016

Cited by 43 publications

(33 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is anticipated that more conclusive results will be drawn on running longer ocean simulations with and without coupling, and after introducing wave-ocean coupling feedbacks within UKC3 (e.g. Staneva et al, 2016).…”

Section: Ocean Model Variablesmentioning

confidence: 99%

“…For example, guidance on the evolution and impact of severe storm surges (e.g. Bertin et al, 2015;Staneva et al, 2016) requires detailed prediction and synthesis of both the atmospheric (pressure, wind) and ocean (tides, waves) states. In addition, numerous high-impact flood events illustrate that floods result from a combination of weather, land and river conditions and an evolving inland flood situation (e.g.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The UKC2 regional coupled environmental prediction system

et al. 2018

View full text Add to dashboard Cite

Abstract. It is hypothesized that more accurate prediction and warning of natural hazards, such as of the impacts of severe weather mediated through various components of the environment, require a more integrated Earth System approach to forecasting. This hypothesis can be explored using regional coupled prediction systems, in which the known interactions and feedbacks between different physical and biogeochemical components of the environment across sky, sea and land can be simulated. Such systems are becoming increasingly common research tools. This paper describes the development of the UKC2 regional coupled research system, which has been delivered under the UK Environmental Prediction Prototype project. This provides the first implementation of an atmosphere-land-ocean-wave modelling system focussed on the United Kingdom and surrounding seas at km-scale resolution. The UKC2 coupled system incorporates models of the atmosphere (Met Office Unified Model), land surface with river routing (JULES), shelf-sea ocean (NEMO) and ocean waves (WAVEWATCH III). These components are coupled, via OASIS3-MCT libraries, at unprecedentedly high resolution across the UK within a north-western European regional domain. A research framework has been established to explore the representation of feedback processes in coupled and uncoupled modes, providing a new research tool for UK environmental science. This paper documents the technical design and implementation of UKC2, along with the associated evaluation framework. An analysis of new results comparing the output of the coupled UKC2 system with relevant forced control simulations for six contrasting case studies of 5-day duration is presented. Results demonstrate that performance can be achieved with the UKC2 system that is at least comparable to its component control simulations. For some cases, improvements in air temperature, sea surface temperature, wind speed, significant wave height and mean wave period highlight the potential benefits of coupling between environmental model components. Results also illustrate that the coupling itself is not sufficient to address all known model issues. Priorities for future development of the UK Environmental Prediction framework and component systems are discussed.

show abstract

Section: Ocean Model Variablesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The UKC2 regional coupled environmental prediction system

et al. 2018

View full text Add to dashboard Cite

show abstract

“…These changes were also predominantly driven by the wave-modified surface stress, with a secondary contribution from Stokes-Coriolis forcing. Staneva et al (2016a), Staneva et al (2016b) and Shloen et al (2017) considered the impact of ocean-wave coupling in the near-coastal German Bight region of the southern Ocean Sci. Discuss., https://doi.org/10.5194/os-2018-148 Manuscript under review for journal Ocean Sci.…”

Section: Introductionmentioning

confidence: 99%

Can wave coupling improve operational regional ocean forecasts for the North-West European Shelf?

Lewis¹,

Sanchez²,

Siddorn³

et al. 2018

Preprint

Self Cite

View full text Add to dashboard Cite

Operational ocean forecasts are typically produced by modelling systems run using a forced mode approach. The evolution of the ocean state is not directly influenced by surface waves, and the ocean dynamics are driven by an external source of meteorological data which is independent of the ocean state. Model coupling provides one approach to increase the extent to which ocean forecast systems can represent the interactions and feedbacks between ocean, waves and the atmosphere seen in 15 nature. This paper demonstrates the impact of improving how the effect of waves on the momentum exchange across the ocean-atmosphere interface is represented through ocean-wave coupling on the performance of an operational regional ocean prediction system. This study focuses on the eddy-resolving (1.5 km resolution) Atlantic Margin Model (AMM15) ocean model configuration for the North-West European Shelf (NWS) region.A series of two-year duration forecast trials of the Copernicus Marine Environment Monitoring Service (CMEMS) North-20 West Shelf regional ocean prediction system are analysed. The impact of including ocean-wave feedbacks via dynamic coupling on the simulated ocean is discussed. The main interactions included are the modification of surface stress by wave growth and dissipation, Stokes-Coriolis forcing and wave height dependent ocean surface roughness. Given the relevance to operational forecasting, trials with and without ocean data assimilation are considered.Summary forecast metrics demonstrate that the ocean-wave coupled system is a viable evolution for future operational 25 implementation. When results are considered in more depth, wave coupling was found to result in an annual cycle of relatively warmer winter and cooler summer sea surface temperatures for seasonally stratified regions of the NWS. This is driven by enhanced mixing due to waves, and a deepening of the ocean mixed layer during summer. The impact of wave coupling is shown to be reduced within the mixed layer with assimilation of ocean observations. Evaluation of salinity and ocean currents against profile measurements in the German Bight demonstrates improved simulation with wave coupling relative to control 30 simulations. Further, evidence is provided of improvement to simulation of extremes of sea surface height anomalies relative to coastal tide gauges.Ocean Sci. Discuss., https://doi.

show abstract

“…Besides this, depths in the southern North Sea are only about 40m on average adding to the fact that wind stress is particularly effective in piling up water against the coast in the shallow water as the effect is inversely proportional to water depth (Wang et al, 2008 It should be kept in mind that besides the prevailing and dominant wind directions responsible for most compound extremes there still exist additional critical directions linked to extremes. For instance in the area of German Bight (southern North Sea), northwest wind components (visible in the wind rose for Weser RIEN) have been identified as having a significant link to both surge and wave extremes (Staneva et al, 2016). 5…”

Section: Wind Rose Diagrams Assessing the Low-level Flow Characteristmentioning

confidence: 99%

Estimations of statistical dependence as joint return period modulator of compound events. Part I: storm surge and wave height

Petroliagkis¹

2017

Preprint

View full text Add to dashboard Cite

Abstract. The possibility of utilising statistical dependence methods in coastal flood hazard calculations is investigated, since flood risk is rarely a function of just one source variable but usually two or more. Source variables in most cases are not independent as they may be driven by the same weather event, so their dependence, which is capable of modulating their joint 10 return period, has to be estimated before the calculation of their joint probability. Dependence and correlation may differ substantially from one another since dependence is focused heavily on tail (extreme) percentiles. The statistical analysis between surge and wave is performed over 32 river ending points along European coasts. Two sets of almost 35-year hindcasts of storm surge and wave height were adapted and results are presented by means of analytical tables and maps referring to both correlation and statistical dependence values. Further, the top 80 compound events were defined for each river ending 15 point. Their frequency of occurrence was found to be distinctly higher during the cold months while their main low-level flow characteristics appear to be mainly in harmony with the transient nature of storms and their tracks. Overall, significantly strong values of positive correlations and dependencies were found over the Irish Sea, English Channel, south coasts of the North Sea, Norwegian Sea and Baltic Sea, with compound events taking place in a zero-lag mode. For the rest, mostly positive moderate dependence values were estimated even if a considerable number of them had correlations of almost zero or even 20 negative value.Nat. Hazards Earth Syst. Sci. Discuss., https://doi

show abstract

Coastal flooding: impact of waves on storm surge during extremes – a case study for the German Bight

Cited by 43 publications

References 53 publications

The UKC2 regional coupled environmental prediction system

The UKC2 regional coupled environmental prediction system

Can wave coupling improve operational regional ocean forecasts for the North-West European Shelf?

Estimations of statistical dependence as joint return period modulator of compound events. Part I: storm surge and wave height

Contact Info

Product

Resources

About