Climate extremes in North America
The North American continent is a continent of extremes from a climatic point of view . Due to its great north-south extent and the topographical situation, extreme climatic conditions occur all year round , especially in the area of the United States of America , which shape the living and economic situation of large parts of the population.
The topographical division of North America with the Rocky Mountains along the west coast and the Appalachians on the east coast, which border the continent in a funnel shape to the south, as well as the adjacent Pacific Ocean in the west, the Atlantic Ocean in the east and the Caribbean Sea or the Gulf of Mexico in the south cause the large-scale and frequent occurrence of extreme weather events. The spatial distribution of these weather events is partly regionally limited (e.g. hurricanes, tornadoes), sometimes very extensive (e.g. cold and heat events). Climate extremes are also called climatic hazards in the English-speaking world . The occurrence of these climatic hazards is primarily concentrated in the continental territory of the United States of America and only in exceptional cases also affects southern Canada and, in the case of hurricanes, the entire Caribbean region and Central America . All extreme events are seasonally limited, but vary greatly in terms of their area of distribution or the size of the affected region.
Humidity and heat
The problem of humid, humid, warm and hot weather affects large parts of the southeastern USA during the summer months. Hot and humid air, which is transported from the Bermuda high over the Gulf of Mexico to far inland, has temperatures of 30–32 ° C and a relative humidity of 75–85%, causes severe stress to the human organism. With simultaneously long hours of sunshine and relative calm, as well as only slight temperature drops during the night, this type of weather represents a great danger, especially for the elderly. The victims actually caused by these conditions can only be estimated imprecisely and scientifically difficult to differentiate from natural deaths, but they are on estimated about 200 per year. The number of victims of individual, extreme heat events can also be significantly higher. A heat wave in Chicago in 1995 led to around 670 deaths. Economic damage is mostly of an indirect nature. However, the immense power consumption of the American population through the use of air conditioning can be at least partially attributed to these events. In 2001, electricity consumption by air conditioning in the USA amounted to approx. 183 TWh, which corresponds to about a third of the total German gross electricity consumption in the same year. Damage to and heavy use of road surfaces and rails can also cause economic disadvantages. The prediction of such heat events is relatively long-term possible through modern weather observation , but the damage caused by them can hardly be prevented. Most likely, it is useful to educate the population about the dangers of this climatic hazard, so that they can then take individual precautions, for example by buying air conditioning and avoiding physical work during the period in question.
Drought and drought
Droughts and periods of drought no longer claim fatalities in modern Western society, in which drinking water is widespread; however, they are a major problem, especially from an economic point of view. They occur during the summer months and threaten practically the entire area of the continental United States and southern Canada. A distinction must be made between meteorologically induced droughts and socio-economic droughts. Meteorological droughts are dry periods in which the amount of precipitation deviates from the mean value, while socio-economic droughts occur where the population's water consumption exceeds the naturally available and renewable water resources. Socio-economic droughts can favor or intensify meteorologically induced droughts due to the excessive consumption of water resources in an area and the resulting lowering of the water table. Meteorological droughts occur more frequently in the Great Plains . Moist, maritime air masses from the Pacific Ocean hit the Rocky Mountains in the course of the west wind drift and rain down on their west side as they rise. The resulting hair dryer effect ( chinook ) causes warm, dry air to arrive east of the Cordilleras , which hardly produces abundant rainfall, although in the continental rainfall regime a summer maximum of rainfall is generally the rule. This geographical peculiarity nevertheless leads to drought periods of several years at regular intervals, which primarily have a severe impact on agriculture in the affected area. The negative effect is intensified by the strong wind carrying away the dry, loose and humus-rich upper layer of soil in dust storms, leaving only sterile soil. Such an extreme drought during the 1930s in the American Midwest led to the coining of the term " Dust Bowl ".
Another danger posed by drought is the increased susceptibility of vegetation to uncontrolled fires. According to a study by the National Drought Mitigation Center , the total economic damage caused by droughts in the United States on average amounts to US $ 6-8 billion. Droughts are difficult to predict because they develop over a longer period of time and are thus beyond the reliable forecast window of the weather services. Therefore, continuous observation and evaluation of dry periods and comparison with historical data is necessary. This task is carried out by the Climate Prediction Center, which is part of the National Oceanic and Atmospheric Administration (NOAA), as well as various university institutions, such as the aforementioned National Drought Mitigation Center (NDMC) of the University of Nebraska-Lincoln . The collected data on precipitation, evapotranspiration , water level and soil moisture are then divided into hazard categories using various indicators and clearly displayed on maps. There are different indicators, each suitable for different areas of application and selected according to the size of the forecast, location of the area and other criteria. The most widely used index is the Palmer Drought Severity Index (PDSI), which is divided into 11 classifications and used by many US government institutions. The PDSI, which was developed in the mid-1960s, has since been further developed and modified several times and is now used or supplemented by other indicators such as the Standard Precipitation Index (SPI) or the Reclamation Drought Index (RDI).
In addition to programs to adapt agricultural activities to the natural environment, preventive measures against drought and its effects are also the switch to more drought-resistant seeds and the unhindered flow of information to those potentially affected. Although these measures cannot prevent the drought, they can at least mitigate the effects on the affected population.
Floods
Floods occur regularly in North America, and here again primarily the US territory is affected. In spring, the areas of the northern Great Plains are affected by seasonally recurring meltwater floods. Floods occur less frequently along the major rivers in the USA, which are triggered by extreme precipitation and have an even more devastating effect. Floods are the most serious climatic extreme in the United States in terms of both fatalities and finances. Between 1975 and 1998, they claimed nearly 2,500 lives and caused financial losses of over $ 100 billion.
The force with which floods hit the population is primarily based on historical factors: floodplains were an attractive settlement area, as they often offered exceptionally good soil quality, which favored agricultural yields; In addition, their evenness made building construction easier. Other favorable factors were - and still are today - the favorable traffic situation and the possibility of generating energy . These diverse advantages explain why many agglomeration areas and large cities are now in the catchment area of potential floods. Avoiding flood damage is only possible to a limited extent due to the size of the affected areas. Protective structures can provide a certain level of protection in the event of smaller floods.
During the great flood in the upper Mississippi Basin in the summer of 1993, for example, over 1,000 of the 1,300 dams along the river were destroyed and the water masses caused damage between 12 and 16 billion US dollars, but the fact that less than 50 fatalities were still due to one good prediction of the course of the flood, its relatively slow progress and the possible evacuation of over 50,000 people. In principle, however, floods are and will remain uncontrollable and their effects can only be limited by limiting new buildings in flood areas and consistently building flood protection facilities and maintaining them regularly.
Flash floods
Flash floods are also a type of flood or flood disaster, but due to their intensity and unpredictability in the affected region, they are much more dangerous than "classic" floods. According to the definition of the National Weather Service (NWS), heavy rainfall triggers a lightning flood within six hours, which can develop into a veritable wall of water in a few minutes even in places that appeared completely dry and safe a short time before. They are often triggered by convection precipitation from tropical-maritime and thus extremely humid air masses. These come from the Gulf of Mexico and are also called gulf air . The Great Plains states of the USA are primarily affected, as well as the two Carolinas, Virginia and Texas, but in principle flash floods can occur anywhere in the USA and southern Canada. In addition to heavy rainfall, a prerequisite for the development of flash floods is a subsoil that is not capable of absorbing water. In addition to parched soils, these can also be soils saturated with water or sealed surfaces such as streets or underpasses. Streams, canyons or depressions also increase the risk of lightning floods and their intensity. Although flash floods only have a narrow regional impact, they claim a high number of deaths each year and cause considerable damage. This is mainly due to their quick and unexpected appearance and thus poor predictability. Nevertheless, the NWS tries to assess the risk for each county in the USA by means of a daily updated "Flash Flood Guidance" map . This is done by determining the amount of precipitation that could trigger a flash flood in a particular region and is based on measurements of soil moisture. The Federal Emergency Management Agency , or FEMA for short, also offers options for determining the individual flood risk in a particular region. The construction of flood control structures can also significantly reduce the risk of flood damage. In addition, the population must be consequently informed, as most deaths are still due to ignorance of how to deal with floods. Most flash flood victims die in their cars because they try to cross flooded street sections and, because of a false sense of security, underestimate the force of the water flow or overlook the undercuts of the roadway hidden under the muddy water and thus get swept away with their vehicle.
Hurricanes
Hurricanes are one of the most important climatic hazards and because of their spectacularity and effect they attract a lot of media attention. Due to the combination of high wind speeds, heavy rainfall and tidal waves released on the coast, they often cause high damage. The official hurricane season begins in June and ends in November, but in principle hurricanes can also occur outside of this time window.
Hurricanes affecting North America arise from tropical low-pressure areas and, due to the necessary effect of the Coriolis force for the rotational movement, can usually only develop about 5 ° north of the equator and above at least 27 ° C warm water. Convection and the release of latent energy at great heights create a high altitude and a strong low pressure area near the water, which leads to strong convergence of other warm and humid air masses. The resulting "thermodynamic energy machine", the hurricane, can intensify further over warm water and then moves at an average speed of 16 - 24 km / h. The speed of rotation of a hurricane can vary widely and depends primarily on the water temperature. From a speed of 120 km / h a tropical storm is called a hurricane. In addition, hurricanes are divided into categories according to the intensity of their rotation speed and assessed on the Saffir-Simpson hurricane wind scale according to their destructive potential.
The state of Florida , the entire Gulf Coast as well as the southeast coastal states of Georgia and the two Carolinas are particularly threatened . Extensions and remnants of the hurricanes can also cause minor damage and floods along the east coast of the USA. The slow development and movement of hurricanes results in long lead times, which can be used by means of early warnings and evacuation instructions to the population. However, since the direction of the train is difficult to predict, such warnings are often fraught with uncertainty and actual evacuations are usually hesitant. In principle, however, an effective hurricane warning system has been set up in the USA that has been able to greatly reduce the number of fatalities. Even the number of victims of Hurricane Katrina can be classified as surprisingly low from a historical perspective. The task of hurricane management in the USA is carried out by several authorities and organizations. On the precautionary side, the NOAA and the NWS should again be mentioned, which are responsible for the forecast and calculation of train paths. For this purpose, the NWS has set up the National Hurricane Center in Miami (Florida) , which is responsible for the earliest possible forecast of emerging hurricanes in the Atlantic and the East Pacific, including those that do not directly threaten the USA. The data required for this are obtained both with close-up methods such as weather stations , buoys, ships and aircraft and with remote-sensing methods such as satellite and radar observation. In turn, FEMA is responsible for initiating preventive measures and, in particular, providing support, rescue and coordination after the hurricane has passed through. It is supported at the regional level by the Emergency Management Offices that exist in many states. These regional institutions specialize above all in educating the population at risk. In order to ensure a smooth process in the event of a recommended evacuation, so-called "Hurricane Escape Ways" have also been set up, which are intended to enable people to escape to less dangerous places. Despite all these efforts, the material damage can only be limited to a small extent due to the force and inevitability of the event. The average annual damage caused by hurricanes between 1975 and 1998 was $ 3.1 billion. Here, however, it also becomes clear how much an extraordinarily loss-intensive year - such as 2005 - can raise the average. The over 100 billion dollars in damage caused in the USA by the hurricane season of 2005 would more than double the average damage to approximately 7.6 billion dollars per year during the period considered above.
Tornadoes
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Along with hurricanes, tornadoes are probably the most spectacular climate threat in North America. In principle, they can occur anywhere in the United States and southern Canada. Their main distribution area, however, is limited to the eastern half of the USA. North Texas , Oklahoma , South Kansas , Nebraska , Illinois , Indiana , Mississippi and Florida are particularly affected. Up to nine tornadoes per year and 10,000 square miles form here.
Tornadoes arise at air mass boundaries where polar-continental and tropical-maritime air masses meet. They form from a thundercloud and mostly move from south-west to north-east following the altitude current. The diameter of the rotating air hose is usually less than a hundred meters and leaves a clearly defined path of devastation. Because of the high wind speeds in both horizontal and vertical directions and the strong drop in air pressure within the tornado, the damage caused is often enormous.
Due to the small area affected and the complex educational conditions, an exact prediction of the location at which a tornado will appear is not possible. Nevertheless, great progress has been made in delimiting an endangered area and thus creating the possibility of warning the population in advance. By using a Doppler radar , it is possible not only to determine the amount of precipitation within a thunderstorm, but also the air turbulence within a super cell . To predict areas at risk of tornado, the NWS has set up the Storm Prediction Center , which provides information to the population and the media with maps that are updated several times a day.
However, due to their short or non-existent advance warning period, tornadoes claim a relatively high number of deaths; in the period 1975–1998 it was an average of 58 per year with an average property damage of 1.5 billion US dollars.
Blizzards, Northers, and frost breaks
Blizzards are arctic cold air advances that can penetrate far into the USA during winter if the zonal west wind drift is interrupted and can produce extremely productive snowfalls through mixing with tropical-maritime air masses. The definition of a blizzard is slightly different on the Canadian and American sides, but each includes a cold, strong wind with heavy snowfalls and / or heavy snowdrifts. A blizzard does not necessarily have to produce its own snowfalls, the drifting of already existing snow masses can also represent a blizzard. Blizzards can reach southern Canada and much of the United States. The Great Plains states are particularly affected, but the entire east coast and the Great Lake region are also hit by blizzards. In the lee of the Great Lakes, there is also the so-called lake effect . It refers to the particularly abundant snowfalls that arise as a result of the warming and humidification of colder air over the Great Lakes. These lightning-fast weather changes and heavy snowfall repeatedly lead to major damage, in particular from power outages, traffic obstructions and the destruction of trees and buildings. A blizzard in March 1993, also known as the Storm of the Century , claimed around 270 lives, caused direct damage of between three and six billion US dollars and crippled the entire eastern United States and Canada. Many deaths from blizzards are due to traffic accidents and heart attacks as a result of overexertion when shoveling snow, the latter especially in the so-called Snow Belt under the influence of the Lake Effect, as this snow is particularly wet and heavy.
Further cold dangers are freezing rain, so-called Northers and the killing frost . In addition to unsafe traffic, freezing rain also causes damage to power lines and vegetation due to its weight. Northers are cold winds that are particularly dangerous due to their wind chill , i.e. the perceived temperature. In extreme cases, they can cause severe frostbite within minutes. Killing frost primarily causes economic damage in Florida and California, where crops are destroyed by cold snaps. For example, two Florida frost events in 1983 and 1985 caused over $ 3 billion in economic damage and destroyed 40% of the state's citrus orchards.
lightning strike
Lightning strike is a climatic hazard that can be described as ubiquitous in the USA and southern Canada. In Canada, the lightning hot spots are in the south of the provinces of Ontario and Saskatchewan and in parts of the province of Alberta . In the United States, lightning is most common in Florida and the central Gulf Coast; however, a high lightning density can be found up to the Great Lakes. A single lightning strike is locally very limited in its effect, but its frequent occurrence makes it extremely dangerous. In fact, lightning strikes are one of the deadliest climatic hazards in the USA, claiming an average of 62 to 69 victims each year. The number of injuries is likely to be ten times higher. The financial damage is difficult to determine because the lightning strike is not always the clear cause of the damage. Estimates vary between $ 25 million and $ 5 billion. The major differences in the damage estimate are also due to the inclusion or non-inclusion of consequential damage such as forest fires. An exact prediction of impact locations is of course not possible, but the fact that 80–90% of all lightning deaths are male shows how great the potential to educate people about personal risk behavior. The NWS has therefore set up its own Lightning Safety website for educational purposes .
Hailstorm
Hailstorms are also a common hazard associated with thunderstorms, typically occurring between April and October and mostly concentrated in the Great Plains. The damage balance is almost the opposite of that of the lightning strike. There are hardly any deaths from hailstorms, but the damage to crops and automobiles can be considerable. The damage here is estimated at around $ 200 million to $ 1 billion.
Downbursts
Downbursts are locally narrowly limited wind events that are part of a thunderstorm. These falling gusts can cause damage similar to those of a smaller tornado and are a particular threat to air traffic close to the ground. Between 1964 and 1985, 26 airplane crashes with over 500 fatalities were attributed to the influence of downbursts. It was only with the newly introduced radar systems that the danger for aircraft taking off and landing could be reduced.
Teleconnections
Teleconnections are the remote effects of certain climate phenomena on a spatially distant region. In the case of North America, these are long-range effects of the El Niño or La Niña phenomenon , which actually has its immediate area of action on the east coast of Australia or on the west coast of South America . Via atmospheric feedback, this phenomenon has an influence on the climate of the North American continent and thus also on the climatic extremes in this area. During the El Niño years, increased activity of the high-altitude wind drift can be observed in the area of North America, which leads to heavy rainfall on the American Pacific coast, lower average temperatures in the southeastern United States and exceptional drought events. In general, during El Niño events in the southern United States, colder and wetter climates can be observed than would "normally" be expected. On the other hand, during the El Niño years there was a decrease in the frequency of hurricanes. This phenomenon is reversed during La Niña years and leads to a stimulated hurricane genesis during these periods.
Web links
- NOAA website
- NOAA hazard watch
- National Weather Service (NWS)
- The Canadian counterpart to it
- National Hurricane Center of the NOAA
- The Climate Prediction Center of the NWS
- National Drought Mitigation Center, University of Nebraska
Individual evidence
- ↑ Glaser, Rüdiger and Klaus Kremb (2006): (Eds.): North and South America. Darmstadt: Scientific Book Society .: 28
- ↑ GLASER & KREMB 2006: 29f
- ^ Cutter, Susan L. (2001): American hazardscapes: the regionalization of hazards and disasters. Washington: Joseph Henry Press .: 99
- ↑ CUTTER 2001: 99
- ↑ Energy Information Administration (EIA): http://www.eia.doe.gov/emeu/reps/enduse/er01_us_figs.html Fig.US-2 accessed on November 4, 2008
- ↑ Federal Statistical Office: http://www.destatis.de/jetspeed/portal/cms/Sites/destatis/Internet/DE/Content/Statistiken/Energie/Tabellen/Content50/ErneuerbareEnergie,templateId=renderPrint.psml , accessed on 4. November 2008
- ↑ CUTTER 2001: 100
- ↑ CUTTER 2001: 98
- ↑ CUTTER 2001: 96f
- ↑ GLASER & KREMB 2006: 31
- ↑ GLASER & KREMB 2006: 31
- ↑ Knutson, Cody, Mike Hayes and Tom Phillips (1998): How to reduce drought risk. Western Drought Coordination Council, available under Archived Copy ( Memento of the original from April 10, 2009 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. See p. B-4
- ↑ CUTTER 2001: 98
- ↑ http://www.cpc.ncep.noaa.gov/
- ↑ http://www.noaa.gov/
- ↑ Archived copy ( Memento of the original dated December 4, 2008 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.
- ↑ Gebhardt, Hans, Rüdiger Glaser, Ulrich Radtke and Paul Reuber (2007) (Eds.): Geography. Physical geography and human geography. Heidelberg: Spectrum .: 529
- ↑ Archived copy ( memento of the original dated November 1, 2008 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.
- ↑ Archived copy ( memento of the original dated November 1, 2008 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.
- ↑ Archived copy ( memento of the original dated November 1, 2008 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.
- ↑ GEBHARDT et al. 2007: 529
- ↑ GLASER & KREMB 2006: 32
- ↑ CUTTER 2001: 80
- ↑ CUTTER 2001: 84f
- ↑ GLASER & KREMB 2006: 32
- ↑ CUTTER 2001: 86
- ↑ CUTTER 2001: 86
- ↑ http://www.srh.noaa.gov/mrx/hydro/flooddef.php
- ↑ GLASER & KREMB 2006: 32
- ↑ GLASER & KREMB 2006: 31
- ↑ http://www.fema.gov/hazard/flood/index.shtml
- ↑ http://www.nssl.noaa.gov/edu/safety/flashflood.html
- ↑ http://www.srh.noaa.gov/meg/presentations/flashflood/index.html
- ↑ http://www.srh.noaa.gov/rfcshare/ffg.php?location=NAT&zoom_map=state&duration=1
- ↑ http://www.srh.noaa.gov/rfcshare/ffg.php?location=NAT&zoom_map=state&duration=1 under “Flash Flood Guidance”
- ↑ https://hazards.fema.gov/femaportal/wps/portal
- ↑ GLASER & KREMB 2006: 31
- ↑ http://www.srh.noaa.gov/meg/presentations/flashflood/index.html , slide 11-14
- ^ Fitzpatrick, Patrick J. (2006): Hurricanes: a reference handbook. Second edition. Santa Barbara: ABC-CLIO, Inc .: 13
- ↑ BARRY & CHORLEY 2003: 270
- ↑ GLASER & KREMB 2006: 32
- ↑ Barry, Roger G. and Richard J. Chorley (2003): Atmosphere, Weather and Climate. Eighth Edition, New York: Routledge .: 272
- ↑ FITZPATRICK 2006: 10
- ^ Buckley, Bruce, Edward J. Hopkins and Richard Whitaker (2004): Weather. A visual guide. Toronto: Firefly Books .: 134
- ↑ GLASER & KREMB 2006: 32
- ↑ Great Hurricane of 1780 Table Atlantic hurricanes with the most casualties
- ↑ http://www.nhc.noaa.gov/index.shtml
- ↑ For the state of Florida, for example, at http://www.floridadisaster.org/
- ↑ See for example http://www.floridadisaster.org/family/
- ↑ GLASER & KREMB 2006: 33
- ↑ CUTTER 2001: 104
- ↑ http://www.aoml.noaa.gov/general/lib/lib1/nhclib/mwreviews/2005.pdf Abstract
- ^ Burt, Christopher C. (2004): Extreme weather: a guide & record book. New York: WW Norton & Company: 175
- ↑ GLASER & KREMB 2006: 35
- ↑ http://www.spc.noaa.gov/faq/tornado/doppler.htm , accessed on November 11, 2008
- ↑ See http://www.spc.noaa.gov/ and especially for the prediction of tornadoes http://www.spc.noaa.gov/products/watch/
- ↑ CUTTER 2001: 87
- ↑ GLASER & KREMB 2006: 33
- ↑ http://www.nws.noaa.gov/glossary/index.php?letter=b on the US-American side and archived copy ( memento of the original from May 20, 2007 in the Internet Archive ) Info: The archive link was inserted automatically and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. on the Canadian side; accessed on November 11, 2008
- ↑ REYNOLDS 2003: 13
- ↑ GLASER & KREMB 2006: 33
- ↑ http://www.nws.noaa.gov/glossary/index.php?letter=l accessed on November 11, 2008
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- ↑ CUTTER 2001: 103
- ↑ CUTTER 2001: 102
- ↑ GLASER & KREMB 2006: 35 and archived copy ( memento of the original from May 20, 2007 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. , accessed November 11, 2008
- ↑ CUTTER 2001: 101f
- ↑ Archived copy ( Memento of the original dated November 27, 2001 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. , accessed November 11, 2008
- ↑ CUTTER 2001: 133f
- ↑ GLASER & KREMB 2006: 35
- ↑ CUTTER 2001: 126
- ↑ Archived copy ( Memento of the original from January 22, 2012 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. , accessed November 12, 2008
- ↑ CUTTER 2001: 94, 126 and archived copy ( memento of the original dated November 2, 2010 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. , accessed November 12, 2008
- ↑ Archived copy ( Memento of the original dated October 31, 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. , accessed November 12, 2008
- ↑ CUTTER 2001: 80
- ↑ http://www.lightningsafety.com/nlsi_info/fast-facts-about-lightning.pdf , accessed on November 12, 2008
- ↑ CUTTER 2001: 126; and archived copy ( memento of the original dated November 2, 2010 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed November 12, 2008
- ↑ Archived copy ( memento of the original dated November 2, 2010 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.
- ↑ CUTTER 2001: 90; 123
- ↑ CUTTER 2001: 90f
- ↑ Archived copy ( memento of the original from October 11, 2008 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. , accessed November 12, 2008
- ↑ See archived copy ( memento of the original from December 19, 2008 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. and archived copy ( memento of the original from August 17, 2014 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. , both accessed November 12, 2008
- ↑ Archived copy ( Memento of the original from March 29, 2010 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. , accessed November 12, 2008
- ↑ GLASER & KREMB 2006: 36
- ↑ GLASER & KREMB 2006: 37
