Using satellite altimetry and tide gauges for storm surge warning

Abstract. The combination of the coarse temporal sampling by satellite altimeters in the deep ocean with the high temporal sampling at sparsely located tide gauges along the coast has been used to improve the forecast of high water for the North Sea along the Danish Coast and for the northeast coast of Australia. For both locations we have tried to investigate the possibilities and limitations of the use of satellite altimetry to capture high frequency signals (surges) using data from the past 20 years. The two regions are chosen to represent extra-tropical and tropical storm surge conditions. We have selected several representative high water events on the two continents based on tide gauge recordings and investigated the capability of satellite altimetry to capture these events in the sea surface height data. Due to the lack of recent surges in the North Sea we focused on general high water level and found that in the presence of two or more satellites we could capture more than 90% of the high water sea level events. In the Great Barrier Reef section of the northeast Australian coast, we have investigated several large tropical cyclones; one of these being Cyclone Larry, which hit the Queensland coast in March 2006 and caused both loss of lives as well as huge devastation. Here we demonstrate the importance of integrating tide gauges with satellite altimetry for forecasting high water at the city of Townsville in northeast Australia.

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Storm Tilo over Europe in November 2007: storm surge and impacts on societal and energy infrastructure

Advances in Geosciences ◽

10.5194/adgeo-49-187-2019 ◽

2019 ◽

Vol 49 ◽

pp. 187-196 ◽

Cited By ~ 1

Author(s):

Anthony James Kettle

Keyword(s):

Water Level ◽

Storm Surge ◽

North Sea ◽

Tide Gauge ◽

Winter Storms ◽

Energy Infrastructure ◽

The North ◽

Short Period ◽

Pressure Centre ◽

The North Sea

Abstract. Storm Tilo on 8–9 November 2007 ranks among the serious winter storms in northern Europe over the past 30 years. Its low pressure centre passed across the northern North Sea, and this led to a cold air outbreak in northwest Europe. Strong north winds across the North Sea contributed to a high storm surge that was serious for coastal regions in eastern England, the Netherlands and Germany. Storm winds and unusually high waves caused shipping accidents and damage to some offshore energy infrastructure. This report presents an outline of the met-ocean conditions and a short overview of storm impacts on societal and energy infrastructure. The progress of the storm surge around the North Sea is analysed using data from the national tide gauge networks. A spectral analysis of the water level data is used to isolate the long period storm surge and short period oscillations (i.e., <4.8 h) from the tidal signal. The calculated skew surge is compared with literature reports for this storm and also with another serious North Sea storm from 31 October–1 November 2006 (Storm Britta). The short period oscillations are compared with the platform and shipping incident reports for the 2 d storm period. The results support previous reports of unusual wave and water level dynamics during some severe regional winter storms.

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Storm Xaver over Europe in December 2013 and its energy meteorological impacts

10.5194/egusphere-egu2020-6029 ◽

2020 ◽

Author(s):

Anthony Kettle

Keyword(s):

Storm Surge ◽

North Sea ◽

Tide Gauge ◽

Offshore Wind ◽

Northern Europe ◽

Energy Infrastructure ◽

The North ◽

Short Period ◽

The North Sea ◽

The Uk

Storm Xaver impacted the northern Europe on 5-6 December 2013. &#160;It developed southeast of Greenland and passed north of Scotland and across southern Norway on a trajectory that led to a cold air outbreak across the North Sea and intense convection activity in northern Europe.&#160; Strong sustained north winds led to a high storm surge that impacted all countries bordering the North Sea. &#160;Storm Xaver was a century scale event with certain locations around the North Sea reporting their highest ever water levels since the start of modern records.&#160; Media reports from the time of the storm chronicle the scale of the disruptions, including many cancelled flights, interrupted rail networks, closed bridges and roads, coastal building collapses, and power blackouts across northern Europe. &#160;Much of this was due to the strong winds, but coastal storm surge flooding was important in the UK, and it led to interrupted port operations around the North Sea.The storm was important for energy infrastructure and particularly for wind energy infrastructure.&#160; In the northern North Sea, petroleum platforms were evacuated and operations closed ahead of the storm as a precautionary measure.&#160; A number of onshore wind turbines were badly damaged by high winds and lightning strikes in the UK and Germany.&#160; Over the North Sea, wind speeds exceeded the turbine shutdown threshold of 25 m/s for an extended period of time, with economic impacts from the loss of power generation.&#160;&#160; In the German Bight, the FINO1 offshore wind energy research platform was damaged at the 15 m level by large waves. &#160;This was the third report of storm damage to this platform after Storm Britta in 2006 and Storm Tilo in 2007. &#160;Researchers have highlighted the need to reassess&#160; the design criteria for offshore wind turbines based on these kinds of extreme meteorological events. &#160;For the offshore wind industry, an important element of energy meteorology is to characterize both the evolving wind and wave fields during severe storms as both elements contribute to turbine loads and potential damage.The present conference contribution presents a literature review of the major events during Storm Xaver and impacts on energy infrastructure.&#160; Tide gauge records are reanalyzed to trace the progress of the storm surge wave around the North Sea.&#160; A spectral analysis is used to separate the long period storm surge component, diurnal/semidiurnal tide, and short period components in the original water level record. &#160;The short period component of the tide gauge record is important as it may be linked with infragravity waves that have been implicated in certain cases of offshore infrastructure damage in addition to coastal erosion. &#160;Discussion is made of offshore wave records during the storm.&#160; Storm Xaver is compared with two damaging offshore storms in 2006 and 2007.

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Assessment of tidal range changes in the North Sea from 1958 to 2014

10.5194/egusphere-egu21-14706 ◽

2021 ◽

Author(s):

Leon Jänicke ◽

Andra Ebener ◽

Sönke Dangendorf ◽

Arne Arns ◽

Michael Schindelegger ◽

...

Keyword(s):

North Sea ◽

German Bight ◽

Large Scale ◽

Tide Gauge ◽

Tidal Range ◽

Tide Gauges ◽

Tide Gauge Records ◽

Large Spatial Scale ◽

The North ◽

The North Sea

Tide gauges throughout the North Sea basin show significant changes in the local tidal regime since the mid-20th century, especially in the German Bight area. These changes were analyzed within the DFG-funded project TIDEDYN (Analyzing long term changes in the tidal dynamics of the North Sea, project number 290112166) and the final results were recently published in J&#228;nicke et al. (2020, https://doi.org/10.1029/2020JC016456).In this paper, we document an exceptional large-spatial scale case of changes in tidal range in the North Sea, featuring pronounced trends between -2.3 mm/yr at tide gauges in the UK and up to 7 mm/yr in the German Bight between 1958 and 2014. These changes are spatially heterogeneous and driven by a superposition of local and large-scale processes within the basin. We use principal component analysis to separate large-scale signals appearing coherently over multiple stations from rather localized changes. We identify two leading principal components (PCs) that explain about 69% of tidal range changes in the entire North Sea including the divergent trend pattern along UK and German coastlines that reflects movement of the region&#8217;s semidiurnal amphidromic areas. By applying numerical and statistical analyses, we can assign a baroclinic (PC1) and a barotropic large-scale signal (PC2), explaining a large part of the overall variance. A comparison between PC2 and tide gauge records along the European Atlantic coast, Iceland and Canada shows significant correlations on time scales of less than 2 years, which points to an external and basin-wide forcing mechanism. By contrast, PC1 dominates in the southern North Sea and originates, at least in part, from stratification changes in nearby shallow waters. In particular, from an analysis of observed density profiles, we suggest that an increased strength and duration of the summer pycnocline has stabilized the water column against turbulent dissipation and allowed for higher tidal elevations at the coast.We would like to present these research results and the content of the paper (cf. J&#228;nicke et al., 2020) at vEGU21, hoping to encourage subsequent questions and further discussions.

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The North Sea surge of 31 October–1 November 2006 during Storm Britta

Advances in Geosciences ◽

10.5194/adgeo-45-273-2018 ◽

2018 ◽

Vol 45 ◽

pp. 273-279 ◽

Cited By ~ 1

Author(s):

Anthony James Kettle

Keyword(s):

The Netherlands ◽

Storm Surge ◽

North Sea ◽

Tide Gauge ◽

Storm Surges ◽

Tide Gauge Records ◽

The North ◽

Short Period ◽

The North Sea ◽

Sea Storm

Abstract. Offshore energy infrastructure, including the petroleum and wind energy sectors, are susceptible to damage and interruption by extreme meteorological events. In northwest Europe and especially the North Sea, these extreme meteorological events are mostly associated with severe storms in the autumn and winter seasons. In the North Sea, storm surges have an impact on the offshore energy sector mainly from the flooding of port facilities and from strong ocean currents causing extra structural loading and bottom scouring. Storm Britta on 31 October–1 November 2006 was an important North Sea storm with a high surge along the coast of the Netherlands and Germany and a significant number of high wave reports. The paper presents an analysis of the national tide gauge records of the United Kingdom, the Netherlands, Germany, and Denmark to spectrally isolate and reconstruct time series components corresponding to the storm surge, semi-diurnal tide, and short period contribution. The semi-diurnal tides and storm surge during Storm Britta are tracked counter-clockwise around the North Sea from Scotland to northern Denmark. The storm surge was remarkable for its pronounced peak in the coastal area between the Netherlands and Germany with no precedent in the ∼100 year measurement record. The short period component of the tide gauge records show large oscillations during the height of the storm that may correspond with reports of unusually high waves at nearby coastal locations.

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Flora and fauna of the sublittoral hard substrata in the Oosterschelde (The Netherlands) — interactions with the North Sea and the influence of a storm surge barrier

North Sea—Estuaries Interactions ◽

10.1007/978-94-009-2000-2_15 ◽

1990 ◽

pp. 189-200

Author(s):

R. J. Leewis ◽

H. W. Waardenburg

Keyword(s):

The Netherlands ◽

Storm Surge ◽

North Sea ◽

The North ◽

The North Sea ◽

Hard Substrata

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Large-scale forcing of the European Slope Current and associated inflows to the North Sea

Ocean Science ◽

10.5194/os-13-315-2017 ◽

2017 ◽

Vol 13 (2) ◽

pp. 315-335 ◽

Cited By ~ 18

Author(s):

Robert Marsh ◽

Ivan D. Haigh ◽

Stuart A. Cunningham ◽

Mark E. Inall ◽

Marie Porter ◽

...

Keyword(s):

Sea Level ◽

North Sea ◽

Tide Gauge ◽

Density Gradients ◽

Current Transport ◽

Tide Gauge Records ◽

The North ◽

Wide Range ◽

The North Sea ◽

Northern North Sea

Abstract. The European Slope Current provides a shelf-edge conduit for Atlantic Water, a substantial fraction of which is destined for the northern North Sea, with implications for regional hydrography and ecosystems. Drifters drogued at 50 m in the European Slope Current at the Hebridean shelf break follow a wide range of pathways, indicating highly variable Atlantic inflow to the North Sea. Slope Current pathways, timescales and transports over 1988–2007 are further quantified in an eddy-resolving ocean model hindcast. Particle trajectories calculated with model currents indicate that Slope Current water is largely recruited from the eastern subpolar North Atlantic. Observations of absolute dynamic topography and climatological density support theoretical expectations that Slope Current transport is to first order associated with meridional density gradients in the eastern subpolar gyre, which support a geostrophic inflow towards the slope. In the model hindcast, Slope Current transport variability is dominated by abrupt 25–50 % reductions of these density gradients over 1996–1998. Concurrent changes in wind forcing, expressed in terms of density gradients, act in the same sense to reduce Slope Current transport. This indicates that coordinated regional changes of buoyancy and wind forcing acted together to reduce Slope Current transport during the 1990s. Particle trajectories further show that 10–40 % of Slope Current water is destined for the northern North Sea within 6 months of passing to the west of Scotland, with a general decline in this percentage over 1988–2007. Salinities in the Slope Current correspondingly decreased, evidenced in ocean analysis data. Further to the north, in the Atlantic Water conveyed by the Slope Current through the Faroe–Shetland Channel (FSC), salinity is observed to increase over this period while declining in the hindcast. The observed trend may have broadly compensated for a decline in the Atlantic inflow, limiting salinity changes in the northern North Sea during this period. Proxies for both Slope Current transport and Atlantic inflow to the North Sea are sought in sea level height differences across the FSC and between Shetland and the Scottish mainland (Wick). Variability of Slope Current transport on a wide range of timescales, from seasonal to multi-decadal, is implicit in sea level differences between Lerwick (Shetland) and Tórshavn (Faroes), in both tide gauge records from 1957 and a longer model hindcast spanning 1958–2012. Wick–Lerwick sea level differences in tide gauge records from 1965 indicate considerable decadal variability in the Fair Isle Current transport that dominates Atlantic inflow to the northwest North Sea, while sea level differences in the hindcast are dominated by strong seasonal variability. Uncertainties in the Wick tide gauge record limit confidence in this proxy.

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