Cold wave
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A cold wave is a weather phenomenon that is distinguished by marked cooling of the air, or the invasion of very cold air, over a large area. It can also be a prolonged period of excessively cold weather, which may be accompanied by high winds that cause excessive wind chills, leading to weather that seems even colder than it is. Cold waves can be preceded or accompanied by significant winter weather events, such as blizzards or ice storms.
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[edit] Effect on persons and economic activity
Exposure to extreme and especially unexpected cold can lead to hypothermia and frostbite, which require medical attention due to the hazards of tissue damage and organ failure. They can cause death and injury to livestock and wildlife. Exposure to cold mandates greater caloric intake for all animals, including humans, and if a cold wave is accompanied by heavy and persistent snow, grazing animals may be unable to reach needed food and die of hypothermia or starvation. They often necessitate the purchase of foodstuffs at considerable cost to farmers to feed livestock.
Extreme winter cold often causes poorly insulated water pipelines and mains to freeze. Even some poorly-protected indoor plumbing ruptures as water expands within them, causing much damage to property and costly insurance claims. Demand for electrical power and fuels rises dramatically during such times, even though the generation of electrical power may fail due to the freezing of water necessary for the generation of hydroelectricity. Some metals may become brittle at low temperatures. Motor vehicles may fail as antifreeze fails and motor oil gels, resulting even in the failure of the transportation system. To be sure, such is more likely in places like Siberia and much of Canada that customarily get very cold weather.
Fires, paradoxically, become even more of a hazard during extreme cold. Water mains may break and water supplies may become unreliable, making firefighting more difficult. The air during a cold wave is typically more dense and any cold air that a fire is is likely to cause a more intense fire because the colder, denser air that the fire draws in contains more oxygen.
Winter cold waves that aren't considered cold in some areas, but cause temperatures significantly below average for an area, are also destructive. Areas with subtropical climates may recognize unusual cold, perhaps barely-freezing, temperatures, as a cold wave. In such places, plant and animal life is less tolerant of such cold as may appear rarely. The same winter temperatures that one associates with the norm for Kentucky, northern Utah, or Bavaria would be catastrophic to winter crops in southern Florida, southern Arizona, or southern Italy that might be grown for wintertime consumption farther north, or to such all-year tropical or subtropical crops as citrus fruits. Likewise, abnormal cold waves that penetrate into tropical countries in which people do not customarily insulate houses or have reliable heating may cause hypothermia and even frostbite.
Cold waves that bring unexpected freezes and frosts during the growing season in mid-latitude zones can kill plants during the early and most vulnerable stages of growth, resulting in crop failure as plants are killed before they can be harvested economically. Such cold waves have caused famines. At times as deadly to plants as drought, cold waves can leave a land in danger of later brush and forest fires that consume dead biomass. One extreme was the so-called Year Without a Summer of 1816, one of several years during the 1810s in which numerous crops failed during freakish summer cold snaps after volcanic eruptions that reduced incoming sunlight.
[edit] Countermeasures
In some places (like Siberia), extreme cold requires that fuel-powered machinery to be used even part-time must be run continuously. Internal plumbing can be wrapped, and persons can often run water continuously through pipes. Energy conservation, difficult as it is in a cold wave, may require such measures as collecting people (especially the poor and elderly) in communal shelters. Even the homeless may be arrested on trumped-up charges and taken to shelters, only to be released when the hazard abates.
People can stock up on food, water, and other necessities before a cold wave. Some may even choose to migrate to places of milder climates, at least during the winter.
Suitable stocks of forage can be secured before cold waves for livestock, and livestock in vulnerable areas might be shipped from affected areas or even slaughtered. Smudge pots can bring smoke that prevents hard freezes on a farm or grove. Vulnerable crops may be sprayed with water that will paradoxically protect the plants by freezing and absorbing the cold from surrounding air. (The freezing of water releases heat that protects the fruit.)
Hospitals can prepare for the admission of victims of frostbite and hypothermia; schools and other public buildings can be converted into shelters.
Most people can dress appropriately and can even layer their clothing should they need to go outside or should their heating fail. They can also stock candles, matches, flashlights, and portable fuel for cooking and wood for fireplaces or wood stoves, as necessary. However caution should be taken as the use of charcoal fires for cooking or heating within an enclosed dwelling is extremely dangerous due to carbon monoxide poisoning.
Adults must remain aware of the exposure that children and the elderly have to cold.
[edit] Modern cold waves (2000-date)
[edit] 2005-2006 European cold wave
Eastern Europe and Russia saw a very cold winter. Some of them saw their coldest on record or since the 1970s. Snow was an abundance in unusual places, such as in southern Spain and Northern Africa. All the winter months that season were well below average.
[edit] 2004-2005 Southern Europe cold wave
All areas of Southern Europe saw an unusually hard winter. This area saw an ice storm which have a 1 in 1000 of happening (need citation). This cold front caused snow in Algeria, which is extremely unusual.
[edit] 2004 January cold outbreak New England
New England was near a record month when frequent arctic fronts caused unusually cold weather. Boston was one of their coldest in 114 years. Virginia Beach had an unusually long period of below freezing weather. One area of New York saw 150 inches of snow in a month.
[edit] 20th century cold waves (pre-2000)
[edit] 1997 Northern Plains cold air Outbreak
Mid January across the Northern U.S. was one of the windiest on record. With a low of alreak -40°F in some places, wind caused bitterly cold wind chills sometimes nearing -80°F. Northern parts of North Dakota saw up to 90 inches of snow. This was one of the most severe cold air outbreaks of the 1990s.
[edit] 1996 Great Midwest cold outbreak
Late January and early February was Northern Minnesota's coldest short term period on record. The record low of -60°F was recored in Tower, Minnesota.
[edit] 1994 Northern US/Southern Canada cold outbreak
January 1994 was the coldest month recorded over many parts of the northeast and north-central United States, as well as Southern Canada, or coldest since the late 1970s in some locations. Many overnight record lows were set. Cold outbreaks continued into February but the severity eased somehwat. The cold also extended further south than usual into Texas bringing snowfall and temperatures lower than -20°F to parts of the state, Florida also experienced cold and snowfall, even once flurries were reported north of Miami and damage to the citrus crop in cenrtal Florida was extensive. Detroit, Michigan saw their coldest temperature since 1985.
[edit] 1989 record cold start to December
In 1989, the central and eastern USA saw one of the coldest Decembers on record. A white Christmas occurred.
[edit] 1985 Great Western cold air outbreak
February 1985 saw the USA's third coldest temperature of -69°F in Peter's Sink, Utah. About a month of severe cold affect a large part of the nation. 1985 became the fouth coldest year on record in the western USA.
[edit] 1983 Record cold December USA
USA had its coldest ever Christmas in 1983. Severely cold winds blew in from Canada and about 70% of the month was colder than average. The 1980s saw the USA's coldest Decembers on record.
[edit] 1982 cold air outbreak
January 1982 was very cold. The Super Bowl, held in Detroit was nicknamed the "freezerbowl" due to the -9°F temperature and -55°F wind chill. This event is also know as Cold Sunday
[edit] 1970s and 1910s
The severe cold outbreak of 1912 caused the longest recorded period of below zero weather. The winter from 1916–1917 until 1917–1918 was very frigid across the USA. In the late 1970s most or all places in the Lower 48 had at least one winter with a memorable cold wave.
