2003 heat wave in Europe

from Wikipedia, the free encyclopedia
2003 heat wave in Europe
Temperature anomaly summer 2003 to 1971-2000
Temperature anomaly summer of 2003 to 1971-2000
storm Heat wave ( omegalage )
Emergence August 1, 2003
resolution August 13, 2003
Maximum temperature 47.3 ° C ( Alentejo , Portugal, August 1 )
Annuality (total) at least about 500
affected areas Algeria , Portugal , Spain , Italy , France , Belgium , United Kingdom , Switzerland , Germany , Austria , Liechtenstein , Slovakia , Slovenia
Victim 20,000-45,000
Damage amount about 13 billion US $ economically

The 2003 heat wave in Europe reached its peak in the first half of August 2003 .

Due to its duration and intensity with new temperature records in numerous cities, the summer of the century by Hoch Michaela is one of the most important recent meteorological phenomena in Europe.

With an estimated 45,000 to 70,000 fatalities and an economic damage of an estimated 13 billion US dollars, it is one of the most casualties of the past 40 years worldwide, was one of the worst natural disasters in Europe of the 100 years before and arguably the worst storm event on the continent since the beginning of modern historiography; France was hit hardest .

Meteorological situation

The heat wave was caused by a pronounced omegalage . The southern European countries were particularly hard hit by the heat wave; Northern Italy , Spain and Portugal in particular suffered, as did the Maghreb Mediterranean coast. In Amareleja in the Alentejo in southern Portugal, the temperature reached a historic high of 47.4 ° C on August 1st.

France recorded the highest temperatures and the longest duration of a heat wave since at least 1950. According to Météo-France, two-thirds of French weather stations measured temperatures above 35 ° C. Temperatures above 40 ° C were recorded in 15% of the cities. The Brittany experienced its heat record of over 40 ° C. 39 ° C was exceeded in Paris. There the summer mean maximum temperatures of 1922 and 1976 were exceeded. The nocturnal heat record since the first records, which began in 1873, was 25.5 ° C in Paris on the night of August 10th to 11th.

Of the more northerly countries, Switzerland , the west and south of Germany and in Great Britain the south were affected. Temperature records of 37.9 ° C were recorded here at Heathrow Airport in England and 32 ° C in Denmark . In Switzerland, temperatures of over 40 ° C were measured for the first time at 41.5 ° C in Grono in the canton of Graubünden . For Germany, August 2003 set the record of 1807 with 4.2 ° C above average.

By contrast, the intensity of this phenomenon was less intense in Belgium , for example, except in the south. In Luxembourg , too , the state agricultural administration was able to measure temperatures above 40 ° C with its network of weather stations. In Oberkorn on the Luxembourg-French border, the previous temperature record for Luxembourg with 40.3 ° C was reached on August 8, 2003. In the north of the Grand Duchy, however, temperatures hardly rose above 37 ° C. The areas east of the Alps were also less badly affected by the heat (but probably by the drought), but in southern Styria 38.5 ° C was measured in Leibnitz in mid-August . The month of August was also a record-breaking average temperature of 23.6 ° C with over 300 hours of sunshine in August, which is almost 80 more than the monthly average, and more than 45.23  tropical days during the summer.

The heat wave was accompanied by less unusual meteorological events, which, however, intensified the consequences.

  • The heat wave was preceded by the beginning of spring and summer with noticeable drought. In France in particular, most of the departments suffered from severe water shortages. The measured precipitation from February to August was everywhere below the normal level. Especially in the east and on Corsica , the precipitation deficit exceeded the 50% mark. In eastern Austria , Slovakia , Slovenia and western Hungary the drought also suffered severe crop losses - for 2003 in eastern Austria, for example, there was a “glaring precipitation deficit” with annual sums of around 350 mm.
  • In addition, the first half of August, especially August 11th and 12th, was characterized by very weak air movements. This prevented the air from mixing, so that the peaks of the ozone values, which were already high at this time of the year, were pushed up. In addition, there was a sharp rise in nitrogen oxides .

All in all, the whole of summer 2003 (June, July, August) was a record summer with mean temperatures of over 4 ° C above the mean from 1961 to 1990 for the triangle of Eastern France – Switzerland – Southern Germany, 3 ° C from Catalonia to Serbia and Central Germany to Sardinia and over 2 ° C for all of Europe including Iceland and northern Algeria, with the exception of Russia, Finland, Portugal and central Sweden.

About the annuality of the event

Like every heat wave of recent years, this one is also seen in connection with the apparent global warming , an assumption that cannot be directly verified for individual events, but a consequence of the statistical probability of occurrence. The Swiss weather service MeteoSchweiz says that "the summer of 2003 redefined the term" hot summer ".“ 2003 is considered a milestone for the investigation of heat waves as a possible consequence of global warming . ”

According to Météo-France “these dog days far surpass everything that has been known since 1873, in terms of intensity and length as well as the high level of temperatures in terms of the lowest, medium and highest values”. Even under the conditions of an earth warming since the mid-19th century, the heat wave was considered to be an extremely unlikely event statistically. A study by the University of Frankfurt speaks - for Germany - of an annuality of 450, another of "at least 500 years" - little is known about August of the year 1540, which was abnormally hot until Christmas, in particular. Another study found an occurrence once every 46,450 years (although the uncertainty of this estimate is very large and the lower threshold of the statistical 90% interval is given as "only" 9000 years).

In fact, such information is put into perspective, as early as the summer of 2015 there was a similarly intense, but much longer and more extensive, hot summer, the summer of 2018 again showed similar characteristics. In relation to the current climate in Europe, which is already 1 ° warmer than the pre-industrial era, the annuality should perhaps even be more likely to be in the range of only a decade. The ZAMG was based on the 250-year HISTALP also demonstrate series that the event of 2003 - not related to the absolute temperature, but the average temperature of its medium-term period - was less abnormal than some heat wave of the 18th, 19th or 20th Century.

Consequences of the heat wave


Europe as a whole

The estimation of heat-related excess mortality , ie the number of heat deaths  - not the victims of a drought or fire consequences of a drought - is in the study of natural hazards relatively new aspect. It is generally assumed that - at least in the middle latitudes of the first world - mortality increases significantly at maximum daily temperatures of over 35 degrees Celsius. The estimates of the total number of victims were increased significantly in the course of the research that followed the exception; one study gave a significantly higher estimate than others at 70,000.

A study coordinated by Jean-Marie Robine, director of the French research institute Inserm , was concluded in spring 2007 with the key statement that the 2003 heat wave in Europe cost a total of 45,000 lives. The Munich Reinsurance Company spoke of 23,000 direct victims in 2003, namely in France 14,800, Italy 4,000, Germany 3,500, Spain 2,000, Portugal 1,300, Great Britain 900, Netherlands 500. - the same situation should apply to the more recent study. In 2004 the Red Cross reported up to 35,000 fatalities.

With these more recent figures, the high Michaela heatwave worldwide in the last 50 years is only represented by the 2004 tsunami , the 1970 and 1991 storm and flood disasters in Bangladesh and 2008 in Myanmar, and the earthquakes in 1976 , 2008 in China and Pakistan in 2008 and Haiti in 2010 exceeded. In Europe, after the Messina earthquake in 1908 (with around 83,000 deaths), it is the second worst natural disaster in the last 100 years and by far the worst known weather event to date - as a single event, apart from famine caused by annual conditions or events in which the weather is only a cofactor was.

However, the methodology of the French study was not repeated for other temperature anomaly events later or before, or for other parts of the world, so that the figure for the several 10,000 victims is initially unique for heat waves in the specialist literature.


Dried up vegetation around the Electoral Palace in Koblenz

The situation in Germany was also dangerous. Forest fires broke out and temperatures rose to over 40 degrees Celsius for the first time since 1983 . The previous German heat record was broken on August 8, 2003 in Perl-Nennig with 40.3 ° C, but this measurement was not officially confirmed by the German weather service .

On August 13, the temperature in Freiburg im Breisgau , Mannheim , Karlsruhe and March was 40.2 ° C.

In Germany, around 3,500 people died as a result of the heat wave, especially weak people such as the sick and the elderly. Contrary to what was initially assumed, the cause of the high mortality rate was not heart attack or cardiac arrest , but lung failure .


The Gardon reservoir that has
fallen dry near Alès ; Mid-August 2003

The heat wave ( Canicule ) in France killed thousands of people, most of them weakened people, i.e. the elderly and the sick. People over 75 years of age were most affected. Here an observation was confirmed that for about 50 years there has been a tendency for mortality to be higher in summer, whereas it used to be the case in winter.

August 11th and 12th were particularly stressful due to the calm. The effect of the heat wave was intensified by the very high night temperatures; the lack of air movement caused a steep increase in nitrogen oxides, which accumulated when the ozone was formed. The morgues filled up very quickly because the bodies could not be stored in uncooled rooms because of the considerable heat. A cooled hangar in the hall of the Paris suburb of Rungis , the logistics center for transports for the food trade, was made available and converted into the largest morgue in France - room for a further 700 dead.

On August 24, there were still 300 bodies in Paris for which no relatives had reported and which were awaiting burial in Rungis and in refrigerated trucks in Ivry-sur-Seine .

If the authorities mobilized in July because of the threat of forest fires , they did not take notice or took notice too late of the human tragedy that unfolded in the wake of the heat wave. The first calls for help came from the overcrowded emergency rooms in the hospitals. When the heat subsided after August 15, the French leaders were blamed for the slowness with which the disaster plan had been launched. The head of the Ministry of Health Lucien Abenhaïm resigned. President Jacques Chirac , resented by his silence by the opposition from the left and far right, made a statement two weeks after the crisis ended when he returned from vacation. He rejected the responsibility of the executive for this tragedy and instead emphasized the lack of solidarity among citizens. Above all, he complained about the weakening social bond, especially with older people. Then he specifically announced the review of the early warning systems as well as the relief and emergency services. Medicine and nursing alike rejected the simplifications and the shifting of responsibility.

On September 3, 2003, Jacques Chirac and the Paris Mayor Bertrand Delanoë attended the funeral of 57 Parisians in the cemetery of Thiais ( Val-de-Marne ), who had been victims of the extreme heat at the beginning of August and who did not care Had reported relatives.

There is disagreement about the exact number of deaths that can be directly attributed to the extreme heat. The French government first reported 3,000 deaths, then 5,000. Funeral home calculations indicated an additional 10,400 deaths, presumably due to the heat wave. According to an initial estimate submitted by the Health Inspectorate to the Ministry of Health, the heat wave in the first half of August claimed 11,435 lives. A study published on September 25 found 14,802 deaths between August 1 and August 20, a 55% increase in mortality for a total of 2 months of life lost for the entire French population when you count the number of deaths within one Year considered.

Several dozen deaths can also be attributed to forest fires. At least 24 deaths had to be mourned by August 12th.


The situation in Portugal was comparable to that in France: The long heat wave between the end of July and August 12 killed 1,316 people, more than half of whom were over 75 years old. However, thanks to the timely use of emergency measures, the number of deaths has remained lower than in 1981 with 1900 deaths at the time. According to the World Health Authority, the increased death rate in summer fell sharply in 2003 compared to 1981 (9% as of September 10th).


In Switzerland, 975 fatalities were attributed to the hot summer.


There were 141 deaths across the country. There were temperature records in Jerez with 45.1 ° C, Badajoz with 45.0 ° C, Huelva with 43.4 ° C, Girona with 41.2 ° C, Burgos with 38.8 ° C, San Sebastián with 38.6 ° C ° C, Pontevedra with 38.2 ° C and Barcelona with 37.3 ° C. In other cities in southern Spain, the records were not broken, although the temperatures were above 40 ° C such as Murcia with 41.8 ° C, Madrid with 38 ° C, Toledo with 42.0 ° C, Seville with 45.2 ° C and Cordoba with 46.2 ° C. In Cordoba the highest temperature was reached during the heat wave in Spain.

Financial damage

The heat wave is expected to cause economic damage of around 13 billion US dollars. The insurance loss is much lower because crop failures and the like cannot be specifically attributed to this one event and consequences such as water and electricity shortages are rarely insured events.

Impact on the ecosystem

There are many effects here, but not just from the one heat wave. In July 2003, the ecological situation in many French departments was already unusually tense. It was caused by a fairly mild winter beginning, followed by a sharp drop in temperature in early January and very low temperatures during spring, which had already caused considerable frost damage in some areas, such as the freezing of many fruit trees and of rape in central France. Temperatures above normal and the lack of water in most of the departments had weakened many ecosystems. The groundwater level had sunk to its lowest level and the vegetation was already drying up at the beginning of August.

Forests: forest fires and ecological stress

The forest damage can be divided into two manifestations, forest fires as well as insect damage and stress due to lack of water.

On the one hand, the numerous fires destroyed many hectares of forest. Serious forest fires occurred mainly in southern France, Spain and Portugal. In Portugal in particular, forest fires devastated 40% of the forest area and killed 18 people. In Spain, 30,000 hectares of forest had disappeared, 1,300 of them in the north-east, in Catalonia.

The French forest, attacked by storms in 1999 , was damaged again by the heat wave. In most regions, many trees suffered from root dryness . In the east of France, the heat wave had favored the invasion of the spruce spruce spruce beetles . Very young plants with weak roots could not withstand the drought and abnormal heat. Younger plantings, laid out 12 to 15 years ago, showed less heat damage than older plantings.

There were also ideal conditions for the bark beetle where the winter storm Uschi caused windthrow in mid-November, in the Eastern Alps. As a result, the amount of damaged wood in Austria increased from 6 million solid cubic meters due to direct wind throwing by another 2 million solid cubic meters due to beetle damage (the latter also occurring in the order of magnitude every following year, before that - except for the 1990s - beetles had been lost since the mid-20th century at 0.5 million cubic meters). Switzerland also recorded a record level of 2 million cubic meters of bark beetle damage (after which the loss quickly fell again).

Arable farming and agriculture

French agricultural production was affected by the heat wave, all the more since the heat wave was preceded by a winter that had damaged many crops with a sharp drop in temperature. In addition, there was an abnormally dry spring almost everywhere: the grain ripened too early and the yields plummeted.

The autumn harvest (corn silage, sunflower seeds, soy, corn kernels, wines) took place about a month early. Hagel closed the heat wave in several departments. Several cultures, especially wine and maize, were destroyed. Elsewhere you could look forward to a wine harvest of excellent quality: Due to the high temperatures, the ripening of the grapes was accelerated. Overall, the 2003 cultivation year produced very concentrated, rather atypical wines.

Feed such as hay, silage or green fodder was completely damaged, which in many departments resulted in a serious shortage of cattle feed.

As a direct result of the heat wave, several million animals died in non-air-conditioned industrial poultry farms.

The economic impact of drought and heat was estimated by the Agricultural Association (Syndicat) as a loss of four billion euros in gross sales. 59 French departments applied for compensation from the Fund for Agricultural Emergencies. According to INRA , in some areas heat losses could have reached 50%. As for some crops or feed, the areas most affected were the Massif Central, the south-west and the east of France.

Other consequences

Water balance

The Danube reached its lowest water level in over a century. B. in the eastern Serbian Prahovo wrecks of ships that had been sunk in the Second World War were visible.

Electricity industry

In France, the state-owned electricity company (EDF) approached large customers at the beginning of July - for the first time in a summer - to prepare for a reduction in electricity consumption. It took over the losses incurred and paid compensation for the production losses.

The National Society for Electricity and Heat (SNET) had to restart its four coal-fired power plants because of the lowered production of the hydropower and nuclear power plants, like in the dead of winter. In order to cope with the energy shortage that had occurred, which resulted from an additional consumption of 6 to 10 percent by the population, some electricity companies were granted special permits so that they could discharge cooling water one degree above the maximum permissible temperature, while the rivers were already discharged at five Degrees warmer than the average for the last 25 years. In Germany, due to the lack of wind, production was impaired by wind energy and similar exemptions were granted.

The underground distribution system of the electricity company EDF was also affected by the increased temperatures. In October, the company estimated the additional financial burden from the heat wave at three billion euros, because the consequences were still noticeable, especially because of the greatly reduced water reserves in the reservoirs.

In many countries, river water-cooled thermal power plants , especially nuclear power plants with their comparatively high specific water consumption, have had to temporarily reduce production or stop it entirely. In contrast, power plants without once-through cooling, such as lignite- fired power plants with pit water cooling or certain gas-fired power plants, were hardly affected . Denmark, largely surrounded by the sea, benefited from the water shortages in Norway, Sweden and Central Europe. It achieved a record export of electricity, mainly generated by coal-fired power stations, because the lakes had sunk to a low level due to the low rainfall.

Infrastructure and buildings

In many French departments, cracks occurred as a result of cracking in the floors of buildings. In this regard, the building regulations should be changed for 2004.

The use of shipping lanes was restricted (canals closed for shipping).


  • Urs Neu, Ester Thalman; ProClim Forum for Climate and Global Change (Ed.): Hitzesommer 2003 - synthesis report . 1st edition. ProClim, Bern 2006, ISBN 3-907630-16-5 (French, content , left on pdf, proclim.ch - focus on Switzerland).
  • Christian-D. Schönwiese: The hot summer of 2003 from a climate-statistical point of view . Colloquium lecture on June 16, 2004. Ed .: Deutsche Meteorologische Gesellschaft. 2004 ( ppt - focus on Germany).
  • Gerald Bell, Timothy Eichler: Exceptional Heat and Dryness in Europe During April – August 2003 . Special Climate Summary. Ed .: Climate Prediction Center / NOAA / NWS / NCEP. (English, online [PDF]).

See also

Web links

Commons : Hitzewelle 2003  - Collection of pictures, videos and audio files

Individual evidence

  1. a b J. Luterbacher and co-workers: How extraordinary was the hot summer of 2003 compared to the last centuries? In: Abstract on the hot summer 2003 . 2005 .; J. Luterbacher, D. Dietrich, E. Xoplaki, M. Grosjean, H. Wanner: European seasonal and annual temperature variability, trends, and extremes since 1500 . In: Science . No. 303 , 2004, pp. 1499-1503 . , quoted based on reference ProClim: synthesis report . 2006, How extreme was the summer of 2003 ?, p. 7 .
  2. Munich Re: The 10 Biggest Natural Disasters of 2003 ( Memento of the original dated December 3, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , munichre.com, accessed November 29, 2013.  @1@ 2Template: Webachiv / IABot / www.munichre.com
  3. a b Jean-Marie Robine, Siu Lan Cheung, Sophie Le Roy, Herman Van Oyen, François R. Herrmann: Report on excess mortality in Europe in Summer 2003 . Ed .: 2003 Heat Wave Project. EU Community Action Program for Public Health, Grant Agreement 2005114 (English, online [PDF]).
  4. a b Munich Reinsurance Company (ed.): Munich Re Analysis “Natural Catastrophes 2003” . 2003, extreme hot summer event - a normal case in the future? ( Press release ). Press release ( Memento of the original from December 3, 2013 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.munichre.com
  5. a b lit. Météo-France: Dossier sur la canicule 2003.
  6. related to the beginning of the instrument measurement in 1761; Schönwieser, Staeger, Trömel, 2004, cit. n. Lit. Schönwiese: Der Hitzesommer 2003 . Ranking analysis of the summer values ​​of the mean temperature in Germany 1761-2007, p. Slide 10 . - see maximum (1761 to 2007) air temperature in Germany
  7. ↑ Maximum temperature in upper grain (ASTA)
  8. The 2003 wine year. (No longer available online.) In: The vintage. Marktgemeinschaft Steirischerwein, archived from the original on July 8, 2010 ; Retrieved November 15, 2008 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.steirischerwein.at
  9. StartClim 2004. (No longer available online.) Central Institute for Meteorology and Geodynamics , archived from the original on March 9, 2009 ; accessed on November 15, 2008 (section starting situation ). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.zamg.ac.at
  10. High ozone pollution in summer 2003. Federal Environment Agency , November 28, 2003, accessed on November 16, 2008 .
  11. Schär et al., 2004, cit. n. Lit. Schönwiese: Der Hitzesommer 2003 . Temperature anomalies summer (JJA) 2003, p. Slide 6 .
  12. ^ Peter A. Stott, DA Stone, MR Allen: Human contribution to the European heatwave of 2003 . In: Nature . No. 432 , 2004, pp. 610–614 , doi : 10.1038 / nature03089 ( abstract ).
  13. How the summer of 2003 redefined the term “hot summer”. MeteoSwiss: Blog , July 17, 2019.
  14. ^ Lit. Météo-France: Dossier sur la canicule 2003. Translated from Wikipedia.
  15. Schönwiese, Frankfurt University Institute for Meteorology and Climatology, quoted in. According to Ref: Munich Re: TOPICSgeo 2003. p. 22.
  16. Christoph Schär, Pier Luigi Vidale, Daniel Lüthi, Christoph Frei, Christian Häberli, Mark A. Liniger, Christof Appenzeller: The role of increasing temperature variability in European summer heatwaves . In: Nature . No. 427 , January 22, 2004, p. 332–336 , doi : 10.1038 / nature02300 (English, abstract , nature.com [PDF]).
  17. ^ Heat , in: ZAMG: Neoklima (accessed on July 21, 2015), cf. esp. Fig. 1: Development of the changeability of the temperature climate in the Alps region 1760–2006.
  18. ^ AJ McMichael, et al .: Climate Change and Human Healths . Ed .: WHO / WMO / UNEP. 1996. , cit. according to Ref. Münchener Rückversicherungs-Gesellschaft: TOPICS geo . Fig.Temperature and mortality in New York and Shanghai , p. 24 .
  19. Statistics study: The hot summer of 2003 killed 70,000 Europeans. In: Der Spiegel. March 23, 2007, accessed November 15, 2008 .
  20. ^ Heat deaths across Europe. World Socialist Web Site wsws.org, September 5, 2003, accessed November 15, 2008 .
  21. ^ Report on excess mortality in Europe during summer 2003. In: ec.europa.eu. February 28, 2007, accessed July 25, 2019 .
  22. Ref: Munich Reinsurance Company: TOPICS geo . Table heat deaths in Europe in summer 2003 , p. 25 .
  23. International Federation of Red Cross and Red Crescent Societies (ed.): World Disasters Report 2004 . 2004 (English, Chapter 2 , ifrc.org [accessed on February 21, 2009]). Chapter 2 ( Memento of the original from December 4, 2013 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / w3.ifrc.org
  24. Natural and man-made disasters 2001: Man-made damage of a new dimension . In: Schweizerische Rückversicherungs-Gesellschaft (Ed.): Sigma . No. 1 , 2002, Table 10 The most deadly catastrophes 1970–2001 , p. 24 ( web document [PDF; accessed November 29, 2013]).
  25. ^ Karl Josef Linden: Centennial Summer 2003 - Part II. Centennial Summer 2003 in Eifel and Voreifel. A look back at the highlights of the hot season. Retrieved November 15, 2008 .
  26. ^ Website of the Verkehrsverein Nennig eV: German heat record in Perl-Nennig on August 8, 2003 , accessed on August 2, 2018
  27. Manfred Frietsch: March: March - Hitzepol und Sonnseite , Badische Zeitung, February 19, 2013, accessed on November 29, 2013.
  28. ^ Deutscher Wetterdienst: Wetterrekorde - Luft Temperatur, dwd.de, accessed on November 29, 2013.
  29. Tablet against the greenhouse effect: Doctors warn of the health dangers of climate change , current research from March 23 on Deutschlandfunk
  30. ^ Christoph Gunkel: Record summer 2003: The forgotten catastrophe of the century. In: Spiegel Online . July 31, 2013, accessed June 9, 2018 .
  31. Denis Hémon, Eric Jougla: Surmortalité liée à la canicule d'août 2003: rapport d'étape: estimation de la surmortalité et principales caractéristiques épidémiologiques. (PDF) September 25, 2003, archived from the original on December 8, 2008 ; Retrieved November 29, 2013 .
  32. Luigi Jorio: "It is often forgotten that climate change also has health consequences". In: swissinfo.ch . June 3, 2019, accessed June 3, 2019 .
  33. a b H. Krehan, G. Steyrer, C. Tomiczek: Bark beetle calamity 2009: causes for different regional infestation developments. At the Federal Research Center for Forests, Natural Hazards and Landscape: bfw.ac.at → Die Borkenkäfer , July 2, 2015, there in particular Figure 1: Comparison of the amount of wood damaged by storm and snow with the bark beetle damage, up to 2009, Figure 2: Development of the bark beetle Amounts of damaged wood in Switzerland and examples 2–6.
  34. ^ The forgotten catastrophe of the century: Shipwreck , einestages.spiegel.de, accessed on November 29, 2013.