Catastrophe modeling firm AIR Worldwide estimates that insured wind losses from Extratropical Cyclone Xaver will range between €700 million [$963 million] and €1.4 billion [$1.926 billion], with the majority of the losses in Denmark, Germany, and the UK. Losses also occurred in the Netherlands, Belgium, Sweden, and Norway.
The strong extratropical cyclone (ETC) known as Xaver came ashore on Thursday, December 5, in Scotland with wind speeds comparable to those of a Category 1 hurricane. It then headed south and moved across the North Sea to the Netherlands, Denmark, and Germany.
“Xaver brought with it a potent combination of hurricane-force gusts, torrential rains, and storm surge, which caused significant travel disruption, power outages, and property damage across parts of the UK, Germany, the Netherlands, Belgium, Denmark, southern Sweden, and Norway,” said Dr. Gerhard Zuba, senior principal scientist, AIR Worldwide.
He added that “reported observation data for the storm include gusts up to 148 km/h [92 mph] and 158 km/h [98 mph] in areas along the Danish and German coasts. Comparisons have been made between Xaver and winter storms Christian, which struck earlier this year, and Anatol in 1999, which also caused significant losses in Denmark. The wind speeds of Xaver were generally not as intense as either of these storms, however.”
AIR explained that “Xaver was first recognized as a low pressure system off the coast of Greenland. It developed into a powerful extratropical cyclone system as it passed north of Scotland on December 5th. Exhibiting a period of very rapid strengthening known as ‘explosive cyclogenesis,’ the system’s central pressure dropped from approximately 1010 millibars late Thursday to a minimum pressure of 975 millibars 24 hours later. This rapid drop in pressure caused wind speeds to soar, reaching the maximum of “Force 12” on the Beaufort scale in some locations.
“From December 5 to December 6, Xaver cut across southern parts of Norway and Sweden and reached its peak intensity over the Baltic Sea with a minimum pressure of 960 mb.”
Dr. Zuba observed: “Xaver is the second severe storm of the 2013/2014 European winter storm season. The first, late October’s Christian, also caused significant damage over a large part of Europe. By comparison, the 2012/2013 season was relatively quiet, while the season before that saw a series of storms impacting Europe. This sort of clustering is typical for the region, where seasons with very low activity and corresponding damage can be followed by seasons with very high activity and correspondingly high accumulations of insured losses.”
Xaver does bear similarities to the destructive February 1, 1953, storm responsible for the North Sea floods, which caused extensive damage from coastal surge in the UK and the Netherlands. The UK has experienced the brunt of Xaver. During the storm’s passage, strong winds disrupted power to nearly 100,000 homes in Scotland and more than 6,500 in Northern Ireland.
Xaver’s surge caused a difference of two meters [6.2 feet] in water height between the front and back of the Thames Barrier. The barrier was closed for two days, preventing the surge from reaching London as it did in 1953. In Germany, officials reported a surge of 4 meters [app.121/2 feet] above sea level in Hamburg. On December 6, the city closed down all 38 of its flood gates in Hamburg. Several streets in Hamburg’s harbor area along the Elbe River were submerged under 6 meters [18.6 feet] of water.
AIR noted, however, that “despite high winds and improved flood protections across the region, structural damage is expected to be limited from Xaver; reported damage has typically been to the outer building envelope, including roofs, windows, and cladding. However, while the size of individual claims is expected to be relatively low, the overall volume of claims is expected to be significant due to the size of the affected area. Flood and coastal storm surge losses will likely be significant.”
AIR’s industry insured loss estimates reflect the following:
• Insured physical damage from wind to onshore property (residential, commercial, industrial, agricultural, auto), both structures and their contents
• Losses to insured forestry in Norway and Sweden
AIR’s insured loss estimates do not include:
• Losses from coastal storm surge and inland flooding
• Business interruption and additional living expenses (ALE) for residential claims for all modeled countries except the UK
• Losses to uninsured properties
• Losses to infrastructure
• Demand surge (AIR’s demand surge function is not triggered by this event)
Source: AIR Worldwide