European windstorm

24 hour animation of Cyclone Xynthia crossing France

Satellite picture of Cyclone Oratia on 30 October 2000

European windstorm is a name given to the strongest extratropical cyclones which occur across the continent of Europe.^[1] They form as cyclonic windstorms associated with areas of low atmospheric pressure that track across the North Atlantic Ocean towards western Europe. They are most common in the winter months. On average, the month when most windstorms form is January. The seasonal average is 4.6 windstorms.^[2] Deep low pressure areas are relatively common over the North Atlantic, sometimes starting as nor'easters off the New England coast, and frequently track past the north coasts of the British Isles and into the Norwegian Sea. However, when they veer south they can affect almost any country in Europe. Commonly affected countries include the United Kingdom, Ireland, Netherlands, Norway, the Faroe Islands and Iceland, but any country in central, northern and especially western Europe is occasionally struck by such a storm system.

These storms cause economic damage of €1.9 billion per year, and insurance losses of €1.4 billion per year (1990–1998). They rank as the second highest cause of global natural catastrophe insurance loss (after U.S. hurricanes).^[3]

Nomenclature

Naming of individual storms

Up to the second half of the 19th century, European windstorms were named after the person who spotted it.^{[citation needed]} Usually, they would be named either by the year, the date, the Saint's day of their occurrence^[4] or any other way that made them commonly known.

Inspired by the practice of the U.S. National Weather Service to assign names to hurricanes and typhoons, a student at the Free University of Berlin (FU), Karla Wege, suggested in 1954 that all high- and low-pressure systems affecting Europe should be given names in order to make tracking the systems simpler. Lows were given female names and highs male names, and the names of notable extratropical cyclones were retired after each event.^[3][5] This practice was soon adopted by the German media.^[6] In 1998 the system changed to alternating male and female names for highs and lows each year.

In November 2002 the "Adopt-a-Vortex" scheme began, which allows members of the public or companies to buy naming rights for a letter chosen by the buyer that are then assigned alphabetically to high and low pressure areas in Europe during each year.^[5] The naming comes with the slim chance that the system will be notable. The money raised by this is used by the meteorology department to maintain weather observations at the Free University.^[3] The FU names became gradually known across some areas of Europe through the press. Even though these are not sanctioned by any official organizations, like the World Meteorological Organization, they are commonly used especially in Germany,^[7] though are not widely used in other countries such as the United Kingdom.

However, a storm may still be named differently in different countries. For instance, the Norwegian weather service also names independently notable storms that affect Norway.^[8] which can result in multiple names being used in different countries they affect, such as:

• 1999 storm "Anatol" in Germany, is known as the "Decemberorkanen" or "Adam" in Denmark and as "Carola" in Sweden.
• 2011 storm "Dagmar" in Norway and Sweden is known as "Patrick" in Germany and "Tapani" in Finland.
• 2013 St. Jude storm in the English media, is known as Christian in German and French (following the Free University of Berlin's Adopt-a-Vortex program) it was named Simone by the Swedish Meteorological and Hydrological Institute, and as the October storm in Danish and Dutch, it was later given the name Allan by the Danish Meteorological Institute following the political decision to name strong storms which affect Denmark.

An alternative Scottish naming system arose in 2011 via social media/twitter which resulted in the humorous naming of Hurricane Bawbag^[9][10][11] and Hurricane Fannybaws. Such usage of the term Hurricane is not without precedent, as the 1968 Scotland storm was referred to as "Hurricane Low Q".^[12]

Name of phenomena

Several European languages use cognates of the word huracán (ouragan, orkan, huragan, orkaan, ураган, which may or may not be differentiated from tropical hurricanes in these languages) to indicate particularly strong cyclonic winds occurring in Europe. The term hurricane as applied to these storms is not in reference to the structurally different tropical cyclone of the same name, but to the hurricane strength of the wind on the Beaufort scale (winds ≥ 118 km/h or ≥ 73 mph).

In English, use of term hurricane to refer to European windstorms is mostly discouraged, as these storms do not display the structure of tropical storms. Likewise the use of the French term ouragan is similarly discouraged as hurricane is in English, as it is typically reserved for tropical storms only.^[13][14] European windstorms in Latin Europe are generally referred to as derivatives of tempestas (tempest, tempête, tempestado), with a root deriving from the Latin, tempus - meaning time.^[15]

Globally storms of this type forming between 30° and 60° latitude are known as extratropical cyclones. The name European windstorm reflects that these storms in Europe are primarily notable for their strong winds and associated damage which can span several nations on the continent. The strongest cyclones are called windstorms within academia and the insurance industry.^[1] The name European windstorm has not been adopted by the UK Met Office in broadcasts (though it is used in their academic research^[16]) the media or by the general public, and appears to have gained currency in academic and insurance circles as a linguistic and terminologically neutral name for the phenomena.

In contrast to some other European nations there is a lack of a widely accepted name for these storms in English. The Met Office and UK media generally refer to these storms as severe gales.^[17] The current definition of severe gales (which warrants the issue of a weather warning) are repeated gusts of 70 mph (110 km/h) or more over inland areas.^[17] European windstorms are also described in forecasts variously as winter storms,^[18] winter lows, autumnal lows, Atlantic lows and cyclonic systems.^{[citation needed]} They are also sometimes referred to as bullseye isobars and dartboard lows in reference to their appearance on weather charts.^{[citation needed]} A Royal Society exhibition has used the name European Cyclones.^[19] with North-Atlantic Cyclone and North-Atlantic windstorms also being used.^[1]

A fictitious synoptic chart of an extratropical cyclone affecting Great Britain & Ireland. The blue and red arrows between isobars indicate the direction of the wind and its relative temperature, while the "L" symbol denotes the center of the "low". Note the occluded cold and warm frontal boundaries.

Cyclogenesis

North Atlantic Oscillation

The state of the North Atlantic Oscillation relates strongly to the frequency, intensity, and tracks of European windstorms.^[20] An enhanced number of storms have been noted over the North Atlantic/European region during positive NAO phases (compared to negative NAO phases) and is due to larger areas of suitable growth conditions. The occurrence of extreme North Atlantic cyclones is aligned with the NAO state during the cyclones' development phase.^[21] The strongest storms are embedded within, and form in large scale atmospheric flow.^[22] It should be kept in mind that, on the other hand, the cyclones themselves play a major role in steering the NAO phase.^[21] Aggregate European windstorm losses show a strong dependence on NAO,^[23] with losses increasing/decreasing 10-15% at all return periods.^[23]

Clustering

Temporal clustering of windstorm events has also been noted, with 8 consecutive storms hitting Europe during the winter of 1989/90. Lothar and Martin in 1999 were separated only by 36 hours. Kyrill in 2007 following only four days after Hanno, and 2008 with Johanna, Kirsten and Emma.^[24][25] In 2011, Xaver (Berit) moved across Northern Europe and just a day later another storm, named Yoda, hit the same area. In December the same year, Friedhelm, Hergen, Joachim and Oliver/Patrick (Cato/Dagmar) struck northern Europe.

Economic impact

Insurance losses

Insurance losses from windstorms are the second greatest source of loss for any natural peril after Atlantic hurricanes in the United States.^[26] Windstorm losses exceed those caused by flooding in Europe. For instance one windstorm, Kyrill in 2007, exceeded the losses of the 2007 United Kingdom floods.^[27] On average, some 200,000 buildings are damaged by high winds in the UK every year.^[28]

Damaged pylon in Germany after Windstorm Kyrill 2007

Energy supplies

European windstorms wipe out electrical generation capacity across large areas, making supplementation from abroad difficult (windturbines shut down to avoid damage and nuclear capacity may shut if cooling water is contaminated or flooding of the power plant occurs). Transmission capabilities can also be severely limited if power lines are brought down by snow, ice or high winds. In the wake of Cyclone Gudrun in 2005 Denmark and Latvia had difficulty importing electricity,^[29] and Sweden lost 25% of its total power capacity as the Ringhals Nuclear Power Plant and Barsebäck nuclear power plant nuclear plants were shut down.^[30]

Cyclone Lothar and Martin in 1999 left 3.4 million customers in France without electricity, and forced EdF to acquire all the available portable power generators in Europe, with some even being brought in from Canada.^[30] These storms brought a fourth of France's high-tension transmission lines down and 300 high-voltage transmission pylons were toppled. It was one of the greatest energy disruptions ever experienced by a modern developed country.^[31]

Following the Great Storm of 1987 the High Voltage Cross-Channel Link between the UK and France was interrupted, and the storm caused a domino-effect of power outages throughout the Southeast of England.^[32] Conversely windstorms can produce too much wind power. Cyclone Xynthia hit Europe in 2010, generating 19000 megawatts of electricity from Germany's 21000 wind turbines. The electricity produced was too much for consumers to use, and prices on the European Energy Exchange in Leipzig plummeted, which resulted in the grid operators having to pay over 18 euros per megawatt-hour to offload it, costing around half a million euros in total.^[33]

Disruption of the gas supply during Cyclone Dagmar in 2011 left Royal Dutch Shell's Ormen Lange gas processing plant in Norway inoperable after its electricity was cut off by the storm. This left gas supplies in the United Kingdom vulnerable as this facility can supply up to 20 percent of the United Kingdom's needs via the Langeled pipeline, fortunately the disruption came at a time of low demand.^[34]

Notable windstorms

Historic windstorms

• Grote Mandrenke, 1362 – A southwesterly Atlantic gale swept across England, the Netherlands, northern Germany and southern Denmark, killing over 25,000 and changing the Dutch-German-Danish coastline.
• Burchardi Flood, 1634 – Also known as "second Grote Mandrenke", hit Nordfriesland, drowned about 8,000–15,000 people and destroyed the island of Strand.
• Great Storm of 1703 – Severe gales affect south coast of England.
• Night of the Big Wind, 1839 – The most severe windstorm to hit Ireland in recent centuries, with hurricane force winds, killed between 250 and 300 people and rendered hundreds of thousands of homes uninhabitable.
• Royal Charter Storm, October 25–26, 1859 – The Royal Charter Storm was considered to be the most severe storm to hit the British Isles in the 19th century, with a total death toll estimated at over 800. It takes its name from the Royal Charter ship, which was driven by the storm onto the east coast of Anglesey, Wales with the loss of over 450 lives.
• The Tay Bridge Disaster, 1879 – Severe gales (estimated to be Force 10–11) swept the east coast of Scotland, infamously resulting in the collapse of the Tay Rail Bridge and the loss of 75 people who were on board the ill-fated train.^[35]
• Eyemouth Disaster, 1881 – A severe storm struck the southeast coast of Scotland. 189 fishermen were killed, most of whom were from the small village of Eyemouth.
• 1928 Thames flood, January 6–7, 1928 – Snow melt combined with heavy rainfall and a storm surge in the North Sea led to flooding in central London and the loss of 14 lives.

Severe storms since 1950

• North Sea flood of 1953 – Considered to be the worst natural disaster of the 20th century both in the Netherlands and the United Kingdom, claiming over 2,500 lives.
• North Sea flood of 1962 – The Storm reached the German coast of the North Sea with wind speeds up to 200 km/h. The accompanying storm surge combined with the high tide pushed water up the Weser and Elbe, breaching dikes and caused extensive flooding, especially in Hamburg. 315 people were killed, around 60,000 were left homeless.
• Gale of January 1976 January 2–5, 1976 – Widespread wind damage was reported across Europe from Ireland to Central Europe. Coastal flooding occurred in the United Kingdom, Belgium and Germany with the highest storm surge of the 20th century recorded on the German North Sea coast.
• Great Storm of 1987 – This storm affected southeastern England and northern France. In England maximum mean wind speeds of 70 knots (an average over 10 minutes) were recorded. The highest gust of 117 knots (217 km/h) was recorded at Pointe du Raz in Brittany. In all, 19 people were killed in England and 4 in France. 15 million trees were uprooted in England.
• 1990 storm series – Between 25 January and 1 March 1990, eight severe storms crossed Europe including the Burns' Day storm (Daria), Vivian & Wiebke. The total costs resulting from these storms was estimated at almost €13 billion.^[36]
• Lothar and Martin,^[37] 1999 – France, Switzerland and Germany were hit by severe storms Lothar (250 kmh/160 mph), and Martin (198 kmh/123 mph). 140 people were killed during the storms. Lothar and Martin together left 3.4 million customers in France without electricity.^[30] It was one of the greatest energy disruptions ever experienced by a modern developed country.^[31] Flooding at the Blayais Nuclear Power Plant resulted in a 'level 2' event on the International Nuclear Event Scale.^[38] The total costs resulting from both storms was estimated at almost 19.2 billion $US.
• Kyrill,^[39] 2007 – Storm warnings were given for many countries in western, central and northern Europe with severe storm warnings for some areas. At least 53 people were killed in northern and central Europe, causing travel chaos across the region.
• Xynthia,^[40] 2010 – A severe windstorm moved across the Canary Islands to Portugal and western and northern Spain, before moving on to hit south-western France. The highest gust speeds recorded at Alto de Orduña (228 km/h/ 142 mph). 50 people were reported to have died.^[41]

Recent storms

• St Jude Storm, October 26–31, 2013 - This storm travelled through the UK, Belgium, the Netherlands, Luxembourg France, Germany, Poland and Scandinavia. The Storm killed 17 people and one person missing. The highest gust was 194.4 kmh/120.8 mph.

• Bodil/Xaver 2013, December 4–10, 2013 - High winds affected nations across Northern Europe, into Central Europe, with a storm surge affecting coasts of the Irish and North Seas.

• Three storms around the Christmas holidays 2013 brought disruption to transportation and electricity supplies. Flooding occurred in France, Belgium and the United Kingdom. The storms were named Bernd, Dirk and Erich by the Free University of Berlin.

See also

Wind scales

• Beaufort scale (10–12+)
• Fujita scale
• Saffir-Simpson scale

References

External links

Wikimedia Commons has media related to Northern Atlantic cyclones.

• Met Office, University of Exeter & University of Reading: Extreme Wind Storms Catalogue
• Free University of Berlin low-pressure naming lists

v t e European windstorms Historical Grote Mandrenke Burchardi flood Great Storm of 1703 Night of the Big Wind Moray Firth fishing disaster Tay Bridge disaster Eyemouth disaster 1900s North Sea flood of 1953 Hurricane Debbie 1961 North Sea flood of 1962 1968 Scotland storm Quimburga 1972 Gale of January 1976 December 1981 windstorm Ex-Hurricane Charley 1986 Great Storm of 1987 Burns' Day storm 1990 New Year's Day Storm 1992 Braer Storm of January 1993 Boxing Day Storm 1998 Anatol 1999 Lothar and Martin 1999 2000s Oratia 2000 Jeanett 2002 Gudrun 2005 Per 2007 Kyrill 2007 Emma 2008 Klaus 2009 Xynthia 2010 Berit 2011 Friedhelm/Bawbag 2011 Joachim 2011 Dagmar 2011 Ulli 2011 Andrea 2012 St Jude 2013 Xaver 2013 Dirk 2013 Anne 2014 See also European windstorm List of European windstorms