Weather phenomenon
A cold wave (known in some regions as a cold snap, cold spell or Arctic Snap) is a weather phenomenon that is distinguished by a cooling of the air. Specifically, as used by the U.S. National Weather Service, a cold wave is a rapid fall in temperature within a 24-hour period requiring substantially increased protection to agriculture, industry, commerce, and social activities. The precise criteria for a cold wave are the rate at which the temperature falls, and the minimum to which it falls. This minimum temperature is dependent on the geographical region and time of year.[1]
In the United States, a cold spell is defined as the national average high temperature dropping below 20 °F (−7 °C).[2] A cold wave of sufficient magnitude and duration may be classified as a cold air outbreak (CAO).[3][4]
Effects
A cold wave 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 to feed livestock at considerable cost to farmers.
Cold spells are associated with increased mortality rates in populations around the world.[5] Both cold waves and heat waves cause deaths, though different groups of people may be susceptible to different weather events.[6] More temperature-attributable deaths occur during a cold wave than in a heat wave,[7][8] though the mortality rate is higher in undeveloped regions of the world. 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 when antifreeze fails or motor oil gels, producing a failure of the transportation system.
Fires 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 denser and thus contains more oxygen, so when air that a fire draws in becomes unusually cold it is likely to cause a more intense fire.[citation needed] However, snow may stop spreading of fires, especially wildfires.
Winter cold waves that are not considered cold in some areas, but cause temperatures significantly below average for an area, are also destructive. Areas with subtropical climates may recognize a cold wave at higher temperatures than other, colder areas of the globe. The cold wave may be recognized at barely freezing temperatures, as these are still unusually cold for the region, and plant and animal life will be less tolerant of such cold. The same winter temperatures that one associates with the norm for Colorado, Ohio, or Bavaria are catastrophic to crops in places like Florida, California, or parts of South America that grow fruit and vegetables in winter.
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 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.
Recent research suggests a possible link between cold waves in North America and extratropical cyclogenesis over the East Atlantic.[9] These may be connected by large-scale atmospheric circulation patterns. [10] Examples include Rossby wave propagation from the North Pacific or an upper-level anticyclone west of Greenland.[11] In Europe, the advection of cold air masses from the northeast emerges as a potential precursor signal for the majority of cold waves, significantly affecting the energy, health, and agricultural sectors of the continent.[12]
Countermeasures
In some places, such as Siberia, extreme cold requires that fuel-powered machinery intended to be used occasionally must be run continually. 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 and taken to shelters, only to be released when the hazard abates.[13] Hospitals can prepare for the admission of victims of frostbite and hypothermia; schools and other public buildings can be converted into shelters.
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.
Most people can dress appropriately and can 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.
Historical cold waves
17th century cold waves (1601–1700)
18th century cold waves (1701–1800)
19th century cold waves (1801–1900)
1835
- Eastern cold wave of January and February 1835. First of three historic U.S. cold waves to hit during the 19th century (1835, 1857, 1899). In January, mercury thermometers froze throughout the Northeast. Mercury froze at −40 °F (−40 °C) in Bangor and Bath, Maine and Montpelier and White River, Vermont. In Connecticut, Hartford hit −27 °F (−33 °C) and New Haven −23 °F (−31 °C), and in Massachusetts, Williamstown hit −30 °F (−34 °C) and Pittsfield −32 °F (−36 °C), all low temperature marks that have never been matched since. In February, Savannah, Georgia the temperature hit 0 °F (−18 °C), 8 °F (4.4 °C) colder than would be reached during the 1899 cold wave later in the century and Charleston South Carolina hit 2 °F (−17 °C).[14]
1836
- Last reported snowfall in Sydney, Australia occurred on 28 June of that year. British settlers in Hyde Park woke up to snow "nearly 1 in (2.5 cm) deep", with the meteorological table in The Sydney Herald recording that on the morning of the snow the temperature dropped to 3 °C (37 °F).[15]
1857
- New England Cold wave of 1857. January 1857 was the coldest month ever recorded in New England. Average month temperatures of 16.7 °F (−8.5 °C) in New Haven, 16.8 °F (−8.4 °C) in Boston, and 19.6 °F (−6.9 °C) in New York City remain coldest months on record in those cities. The worst of the cold descended on New England on January 22 with January 23 being one of the coldest days known in the region. In Bath, Maine a temperature reading of −52 °F (−47 °C) and in Franconia, New Hampshire −51 °F (−46 °C) were recorded. In Norwich, Vermont −44 °F (−42 °C) was recorded. Boston suburbs of Malden and West Newton recorded −30 °F (−34 °C) overnight. Boston temperatures for January 23 never rose above 0 °F (−18 °C) all day and Nantucket Island was connected to the mainland by ice. In New York City, Erasmus Hall in Brooklyn reached a high of 0 °F during the day and the Hudson River froze over solidly enough for people to walk across to Hoboken.[16]
1859
- January 1859: January 10 – coldest single daytime temperatures ever recorded experienced in New York City and in New England areas. Montreal recorded temperature of −43.6 °F (−42.0 °C) at 7 am, some 15 °F (8.3 °C) degrees lower than modern Montreal record of −29 °F (−34 °C) in 1933. Toronto recorded −27 °F (−33 °C) on the same day. At the University of Vermont in Burlington, −31.5 °F (−35.3 °C) was recorded at 7 am and −26 °F (−32 °C) at 2 pm. In Woodstock, Vermont a temperature of −45 °F (−43 °C) was recorded. Harvard College recorded −4.5 °F (−20.3 °C) at 2 pm and −18 °F (−28 °C) the next morning of January 11, the lowest known temperature reading recorded in Boston. Nantucket Island measured −12 °F (−24 °C), 6 °F (3.3 °C) colder than the modern known record. In New York City, recorded temperatures did not go above 0 °F (−18 °C). In Brooklyn Heights, a recorded reading of −9 °F (−23 °C) at noon and in Eramus Hall in Brooklyn recorded a high of −3.7 °F (−19.8 °C) at 7 am and −8 °F (−22 °C) at 9 pm that night. Union Hall in Jamaica Queens recorded −12 °F (−24 °C) at midnight between January 10 and 11. In White Plains, there were readings of −13 °F (−25 °C) at 7 am, −10 °F (−23 °C) at 2 pm, and −15 °F (−26 °C) at 9 pm.[17]
1874–1875
- Winter 1874–1875 in Mid-Western United States.
1882–1883
- Winter 1882–1883 in United States.
1886–1887
1888
- 1888 US cold wave – A severe cold wave that passed through the Pacific Northwest. It led to a blizzard for the northern Plains and upper Mississippi valley where many children were trapped in schoolhouses where they froze to death.
1893
- 1893 East Asia Cold Wave – Produced snow in Hong Kong and South China, and freezing temperatures into tropical latitudes.
- 1893 Eastern United States Cold Wave.
1895
1899
20th-century cold waves (1901–2000)
1904
- The winter of 1904 was the coolest year on record worldwide.[19]
1912
1916-1917
- Winter of 1916–1917 – the "extended winter" (October to March) of 1916–17 was the coldest on record in the West and Midwest.
1917-1918
- Winter of 1917–1918 – The winter was very frigid across the East and created a heating fuel crisis equaled only in January 1977. Severe cold wave in December 1917 and January 1918 in northeast. December 30 set a number of record lows at the time in New York City (−13 °F, −25 °C) and Boston (−15 °F, −26 °C).[20] Under ideal conditions for radiational cooling, including fresh snow cover and mostly clear skies, the morning of December 30, 1917, was exceptionally cold also in parts of Virginia and West Virginia, with all-time record cold temperatures (that stand until nowadays) recorded in many cities, including −37 °F (−38 °C) at Lewisburg (West Virginia state record), −34 °F (−37 °C) at White Sulphur Springs, West Virginia, −25 °F (−32 °C) at Bluefield, West Virginia, and −27 °F (−33 °C) at Blacksburg and Burke's Garden, Virginia. January 1918 also brought persistent well below average temperatures for many parts of the East and Midwest, with another shot of very cold air in early February (New York City Central Park's high of only 4 °F (−16 °C) on February 5 is a monthly record, while Michigan's Houghton Lake reached a low of −48 °F (−44 °C) on February 1). The Ohio River froze solidly along its entire length.
- This cold wave occurred not only in America but also East Asia. In Seoul, the weather was warm in early December 1917, but the temperature didn't go above (32 °F, 0 °C) during the cold wave from December 15–January 9. In addition, the temperature went lower than (14 °F, −10 °C) from December 15–31. The cold wave was especially fierce from December 26–27 and the low temperature on December 26 was (0.32 °F, −17.60 °C), while the high temperature was (9.86 °F, −12.30 °C). That day Incheon recorded a high temperature of (9.14 °F, −12.70 °C), this was the 3rd lowest high temperature recorded during winter. Also, the low temperature on December 27 was (−4.72 °F, −20.40 °C), this temperature is 2nd coldest temperature recorded in December in Seoul. (The lowest was (−9.58 °F, −23.10 °C) on December 31, 1927). The cold wave continued into January 1918, where it intensified. The low temperature on January 3 was (−7.24 °F, −21.80 °C). The temperature was a slightly warmer on January 14, but the weather was still quite cold, and the low temperatures were at (14 °F, −10 °C) or lower until January 28. Leading into February, this cold wave dissipated. Seoul was had an average temperature of (21.74 °F, −5.70 °C) in December 1917, the lowest average recorded in December, and recorded an average temperature of (18.5 °F, −7.5 °C) in January 1918, the 6th lowest recorded in January.[21]
- The cold wave also impacted North Korea, and the lowest temperature in Pyeongyang was (−11.74 °F, −24.30 °C)[22] in December 1917. Also, the average temperature was (12.56 °F, −10.80 °C).)[23]
1930
- A cold wave gripped the western United States in January 1930. Two inches of snow fell in Palm Springs, CA on January 11, one of only two times in the city's history that snow was ever observed.[24]
1932
- Major cold outbreaks affected California in January, February and December. Up to two inches of snow fell across the Los Angeles Basin on January 15, and two inches of snow was officially recorded at the Downtown Los Angeles Weather Bureau Office.[25] Snow also fell in San Francisco on three days in December 1932.
1933
- 1933 Western United States cold wave – The winter of 1932–33 was the second- or third-coldest on record[26] in most of the West (the coldest on record in Arizona[27]) and saw record cold temperatures in Seneca, Oregon (-54 °F/-48 °C), Moran, Wyoming (-66 °F/-54 °C) and Seminole, Texas (-23 °F/-31 °F) between February 7 and 10,[28] when sixty deaths were blamed on extreme cold and ice storms.
1934
- February 1934 Cold Wave in New England and Eastern Canada – Longest period of cold weather ever experienced to this point. Average temperatures in upper New England and Eastern Canada were around zero degrees Fahrenheit for most of the month. Lake Ontario was reportedly completely frozen over. Temperatures reached above freezing only on one day in Burlington, VT in February.[29]
1936
- 1936 North American cold wave – The cold wave of 1936 was the only cold wave of the 1930s to severely impact the United States east of the hundredth meridian. One of the coldest winters in the Great Plains on record. Low temperatures dropped below −50 °F (−46 °C) in Malta, Montana on four separate days and most of Montana averaged 20 degrees below normal for the entire month of February Parshall, North Dakota hit −60 °F (−51 °C) on February 15, still a record. Langdon, North Dakota remained below 0 °F (−18 °C) for 41 straight days from January 11 to F