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65-792: The North American Ice Storm of 1998 (also known as the Great Ice Storm of 1998 or the January Ice Storm ) was a massive combination of five smaller successive ice storms in January 1998 that struck a relatively narrow swath of land from eastern Ontario to southern Quebec , New Brunswick and Nova Scotia in Canada, and bordering areas from northern New York to central Maine in the United States. It caused massive damage to trees and electrical infrastructure throughout

130-634: A tectonic uplift can significantly alter their major elements, such as the jet stream , and plate tectonics may shift ocean currents . During the extremely hot climates of the Mesozoic , a third desert belt may have existed at the Equator . The wind belts girdling the planet are organised into three cells in each hemisphere—the Hadley cell , the Ferrel cell, and the polar cell. Those cells exist in both

195-515: A cool breeze from the sea that replaces the risen air. At night, the relatively warmer water and cooler land reverses the process, and a breeze from the land, of air cooled by the land, is carried offshore by night. The Pacific cell is of such importance that it has been named the Walker circulation after Sir Gilbert Walker , an early-20th-century director of British observatories in India , who sought

260-443: A layer of sub-freezing temperatures closer to the surface. Frozen precipitation melts to rain while falling into the warm air layer, and then begins to refreeze in the cold layer below. If the precipitate refreezes while still in the air, it will land on the ground as sleet . Alternatively, the liquid droplets can continue to fall without freezing, passing through the cold air just above the surface. This thin layer of air then cools

325-538: A means of predicting when the monsoon winds of India would fail. While he was never successful in doing so, his work led him to the discovery of a link between the periodic pressure variations in the Indian Ocean , and those between the eastern and western Pacific, which he termed the " Southern Oscillation ". The movement of air in the Walker circulation affects the loops on either side. Under normal circumstances,

390-531: A month in theory (see chaos theory and the butterfly effect ). The Earth's weather is a consequence of its illumination by the Sun and the laws of thermodynamics . The atmospheric circulation can be viewed as a heat engine driven by the Sun's energy and whose energy sink , ultimately, is the blackness of space. The work produced by that engine causes the motion of the masses of air, and in that process it redistributes

455-458: A result of the Coriolis effect . The air flows at the surface are called the polar easterlies, flowing from northeast to southwest near the north pole and from southeast to northwest near the south pole. The outflow of air mass from the cell creates harmonic waves in the atmosphere known as Rossby waves . These ultra-long waves determine the path of the polar jet stream , which travels within

520-476: A secondary circulation feature, whose existence depends upon the Hadley and polar cells on either side of it. It might be thought of as an eddy created by the Hadley and polar cells. The air of the Ferrel cell that descends at 30° latitude returns poleward at the ground level, and as it does so it deviates toward the east. In the upper atmosphere of the Ferrel cell, the air moving toward the equator deviates toward

585-679: A shallow layer of cold air trapped at the surface. Such a favorable cold air damming happens with an east to northeasterly flow in the St. Lawrence (the predominant wind direction in the St. Lawrence Valley is usually either northeast or southwest) and the Ottawa Valley and along the axis of the Appalachian Mountains . Snow is produced at upper levels in such a winter storm system, but it eventually melts into rain as it falls through

650-405: A simple system with strong convection drivers. Though cool and dry relative to equatorial air, the air masses at the 60th parallel are still sufficiently warm and moist to undergo convection and drive a thermal loop . At the 60th parallel, the air rises to the tropopause (about 8 km at this latitude) and moves poleward. As it does so, the upper-level air mass deviates toward the east. When

715-465: A storm left 30 millimetres (1.2 in) to 40 millimetres (1.6 in) of ice in Montreal in 1961. Prior to the 1998 storm, the last major ice storm to hit Montreal (1961) deposited around 30 to 60 millimetres (1.2 to 2.4 in) of ice. However, the 1998 storm left deposits twice as thick, downing power lines all over the region, damaging most of the trees in Montreal, and leaving streets covered in

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780-603: A surface wind to push it into the area of the east Pacific. This and the corresponding effects of the Southern Oscillation result in long-term unseasonable temperatures and precipitation patterns in North and South America, Australia, and Southeast Africa, and the disruption of ocean currents. Meanwhile, in the Atlantic, fast-blowing upper level Westerlies of the Hadley cell form, which would ordinarily be blocked by

845-637: A thick, impassable layer of ice. On January 4, 1998, an upper level low system stalled over the Great Lakes , pumping warm and moist air from the Gulf of Mexico toward the upper St. Lawrence Valley. The upper flow then turned eastward, bringing this air mass down toward the Bay of Fundy . At the same time, a high pressure center was sitting farther north in Labrador , keeping an easterly flow of very cold air near

910-419: A warm air layer of above-freezing temperature (of at least 1,200 feet (370 m) in-depth) associated with the overrunning. The rain passes through colder air near the surface and is supercooled . When that rain touches the ground or any other cold surface in the cold air below, the droplets freeze on contact, creating accumulations of ice. If the cold air layer is too thick, the droplets refreeze before hitting

975-405: A wind pattern which pushes Pacific water westward and piles it up in the western Pacific. (Water levels in the western Pacific are about 60 cm higher than in the eastern Pacific.). The daily (diurnal) longitudinal effects are at the mesoscale (a horizontal range of 5 to several hundred kilometres). During the day, air warmed by the relatively hotter land rises, and as it does so it draws

1040-405: Is a result of the highest solar radiation per unit area (solar intensity) falling on the tropics. The solar intensity decreases as the latitude increases, reaching essentially zero at the poles. Longitudinal circulation, however, is a result of the heat capacity of water, its absorptivity, and its mixing. Water absorbs more heat than does the land, but its temperature does not rise as greatly as does

1105-476: Is easily capable of shutting down entire metropolitan areas. Additionally, the loss of power during ice storms has indirectly caused numerous illnesses and deaths due to unintentional carbon monoxide (CO) poisoning . At lower levels, CO poisoning causes symptoms such as nausea , dizziness , fatigue , and headache , but high levels can cause unconsciousness , heart failure , and death. The relatively high incidence of CO poisoning during ice storms occurs due to

1170-467: Is in December to March, the movement of the thermal equator to higher southern latitudes takes place then. The Hadley system provides an example of a thermally direct circulation. The power of the Hadley system, considered as a heat engine, is estimated at 200 tera watts . Part of the air rising at 60° latitude diverges at high altitude toward the poles and creates the polar cell. The rest moves toward

1235-494: Is to understand the long-term effects of the prenatal exposure to stress on the physical growth and functioning, cognitive development, and behaviour of the Project Ice Storm children by studying developmental trajectories through age 13. 45°07′N 73°40′W  /  45.11°N 73.67°W  / 45.11; -73.67 Ice storm The formation of ice begins with a layer of above-freezing air above

1300-410: The 70th parallel north . While the Hadley, Ferrel, and polar cells (whose axes are oriented along parallels or latitudes) are the major features of global heat transport, they do not act alone. Temperature differences also drive a set of circulation cells, whose axes of circulation are longitudinally oriented. This atmospheric motion is known as zonal overturning circulation . Latitudinal circulation

1365-656: The Korean War , with over 16,000 Canadian Forces personnel deployed, 12,000 in Quebec and 4,000 in Ontario at the height of the crisis. Freezing rain is common in the eastern half of Canada and New England , generally occurring at the narrow boundary between cold air from the east and north and moist air from the south. Typically, a warm air mass will travel northward along the Mississippi Valley and overrun

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1430-579: The downtown core were cordoned off by police due to the dangers of large sheets of ice falling from buildings. The area south of Montreal ( Montérégie ) was so affected that the triangle formed by Saint-Hyacinthe , Granby and Saint-Jean-sur-Richelieu was nicknamed the triangle noir ("dark or black triangle") by the French-language media, and the Triangle of Darkness in English media, for

1495-450: The Hadley cell are called the trade winds. Though the Hadley cell is described as located at the equator, it shifts northerly (to higher latitudes) in June and July and southerly (toward lower latitudes) in December and January, as a result of the Sun's heating of the surface. The zone where the greatest heating takes place is called the " thermal equator ". As the southern hemisphere's summer

1560-615: The United States and the Canadian Forces, to help restore power to affected homes in eastern Ontario and western Quebec. Roughly 700,000 of Maine 's 1.2 million residents were without electricity, the Maine National Guard was mobilized, and hundreds of utility crews from as far away as North Carolina arrived to help. With 8 deaths, this became the deadliest natural disaster in Maine history. Three weeks after

1625-509: The United States, most ice storms occur in the northeastern region , but damaging storms have occurred farther south; an ice storm in February 1994 resulted in tremendous ice accumulation as far south as Mississippi, and caused reported damage in nine states. The freezing rain from an ice storm covers everything with heavy, smooth glaze ice . In addition to hazardous driving or walking conditions, branches or even whole trees may break from

1690-506: The Walker circulation and unable to reach such intensities. These winds disrupt the tops of nascent hurricanes and greatly diminish the number which are able to reach full strength. El Niño and La Niña are opposite surface temperature anomalies of the Southern Pacific, which heavily influence the weather on a large scale. In the case of El Niño, warm surface water approaches the coasts of South America which results in blocking

1755-468: The Western Pacific are affected. First, the upper-level westerly winds fail. This cuts off the source of returning, cool air that would normally subside at about 30° south latitude, and therefore the air returning as surface easterlies ceases. There are two consequences. Warm water ceases to surge into the eastern Pacific from the west (it was "piled" by past easterly winds) since there is no longer

1820-476: The adjacent zones of Hadley or Ferrel cells, and which typically have light winds, sunny skies, and little precipitation. The atmospheric circulation pattern that George Hadley described was an attempt to explain the trade winds . The Hadley cell is a closed circulation loop which begins at the equator. There, moist air is warmed by the Earth's surface, decreases in density and rises. A similar air mass rising on

1885-436: The air reaches the polar areas, it has cooled by radiation to space and is considerably denser than the underlying air. It descends, creating a cold, dry high-pressure area. At the polar surface level, the mass of air is driven away from the pole toward the 60th parallel, replacing the air that rose there, and the polar circulation cell is complete. As the air at the surface moves toward the equator, it deviates westwards, again as

1950-408: The area, leading to widespread long-term power outages. Millions were left in the dark for periods varying from days to several weeks, and in some instances, months. It led to 34 fatalities, a shutdown of activities in large cities like Montreal and Ottawa , and an unprecedented effort in reconstruction of the power grid. The ice storm led to the largest deployment of Canadian military personnel since

2015-399: The electrical grid had to be undertaken. With many roads impassable due to heavy snowfall or fallen trees, broken power lines and coated with a heavy layer of ice, emergency vehicles could hardly move. On January 7, the provinces of New Brunswick, Ontario, and Quebec requested aid from the Canadian Forces (CF), and Operation Recuperation began on January 8. Over 15,000 troops were deployed. It

January 1998 North American ice storm - Misplaced Pages Continue

2080-416: The end of the ice storm, there were still thousands of people without electricity. In Quebec alone, 150,000 people were without electricity as of January 28. Estimates of material damage reached around $ 2 billion Canadian for Quebec alone. Overall estimates are around $ 4–6 billion US$ for all the areas affected. Damage to the power grid was so severe that major rebuilding , rather than repairing, of

2145-477: The energy absorbed by the Earth's surface near the tropics to the latitudes nearer the poles, and thence to space. The large-scale atmospheric circulation "cells" shift polewards in warmer periods (for example, interglacials compared to glacials ), but remain largely constant as they are, fundamentally, a property of the Earth's size, rotation rate, heating and atmospheric depth, all of which change little. Over very long time periods (hundreds of millions of years),

2210-406: The equator where it collides at 30° latitude with the high-level air of the Hadley cell. There it subsides and strengthens the high pressure ridges beneath. A large part of the energy that drives the Ferrel cell is provided by the polar and Hadley cells circulating on either side, which drag the air of the Ferrel cell with it. The Ferrel cell, theorized by William Ferrel (1817–1891), is, therefore,

2275-460: The equator, or a high pressure zone at 30° latitude that moves poleward, will accelerate the Westerlies of the Ferrel cell. A strong high, moving polewards may bring westerly winds for days. The Ferrel system acts as a heat pump with a coefficient of performance of 12.1, consuming kinetic energy from the Hadley and polar systems at an approximate rate of 275 terawatts. The polar cell is

2340-609: The flooding farther south from the same storm system. The bridges and tunnels linking Montreal with the South Shore were closed because of concerns about weight tolerances or ice chunks falling from the superstructures. All but one power linkage to the island of Montreal were down for several days, disabling both of the city's water pumping stations. When power was restored, parts of Montreal remained impassable due to large chunks of ice falling from rooftops, which endangered pedestrians and motorists; large portions of Old Montreal and

2405-446: The form of massive terrain features or high pressure zones. The weaker Westerlies of the Ferrel cell, however, can be disrupted. The local passage of a cold front may change that in a matter of minutes, and frequently does. As a result, at the surface, winds can vary abruptly in direction. But the winds above the surface, where they are less disrupted by terrain, are essentially westerly. A low pressure zone at 60° latitude that moves toward

2470-658: The ground and form ice pellets , which are usually less hazardous. The Montreal area typically receives freezing rain between 12 and 17 times a year, averaging between 45 and 65 total hours of rain. However, a freezing rain storm usually lasts only a few hours and leaves a few millimeters (fractions of an inch) of accumulation. It renders roads and sidewalks slippery, causing minor traffic collisions, but road crews use de-icing material to take care of it. Power lines and other equipment are built according to tough standards, since large accumulation events have happened many times prior to 1998. In Quebec, standards were reinforced after

2535-423: The land. As a result, temperature variations on land are greater than on water. The Hadley, Ferrel, and polar cells operate at the largest scale of thousands of kilometers ( synoptic scale ). The latitudinal circulation can also act on this scale of oceans and continents, and this effect is seasonal or even decadal . Warm air rises over the equatorial, continental, and western Pacific Ocean regions. When it reaches

2600-401: The logistical support required to sustain the operation. Project Ice Storm ( Projet Verglas ) was created to monitor the long-term effect of prenatal stress . Researchers at McGill University set up the project in the immediate aftermath of the disaster, finding 178 families to participate; some of the women were still pregnant at the start of the investigation. "The goal of the current study

2665-406: The loop of the Hadley cell. The poleward movement of the air in the upper part of the troposphere deviates toward the east, caused by the coriolis acceleration . At the ground level, however, the movement of the air toward the equator in the lower troposphere deviates toward the west, producing a wind from the east. The winds that flow to the west (from the east, easterly wind) at the ground level in

January 1998 North American ice storm - Misplaced Pages Continue

2730-490: The mid-latitudes are sometimes known as the "zone of mixing." The Hadley and polar cells are truly closed loops, the Ferrel cell is not, and the telling point is in the Westerlies, which are more formally known as "the Prevailing Westerlies." The easterly Trade Winds and the polar easterlies have nothing over which to prevail, as their parent circulation cells are strong enough and face few obstacles either in

2795-410: The northern and southern hemispheres. The vast bulk of the atmospheric motion occurs in the Hadley cell. The high pressure systems acting on the Earth's surface are balanced by the low pressure systems elsewhere. As a result, there is a balance of forces acting on the Earth's surface. The horse latitudes are an area of high pressure at about 30° to 35° latitude (north or south) where winds diverge into

2860-399: The other side of the equator forces those rising air masses to move poleward. The rising air creates a low pressure zone near the equator. As the air moves poleward, it cools, becomes denser, and descends at about the 30th parallel , creating a high-pressure area . The descended air then travels toward the equator along the surface, replacing the air that rose from the equatorial zone, closing

2925-627: The pipes. Atmospheric circulation Atmospheric circulation is the large-scale movement of air and together with ocean circulation is the means by which thermal energy is redistributed on the surface of the Earth . The Earth's atmospheric circulation varies from year to year, but the large-scale structure of its circulation remains fairly constant. The smaller-scale weather systems – mid-latitude depressions , or tropical convective cells – occur chaotically, and long-range weather predictions of those cannot be made beyond ten days in practice, or

2990-402: The polar cell are similar in that they are thermally direct; in other words, they exist as a direct consequence of surface temperatures. Their thermal characteristics drive the weather in their domain. The sheer volume of energy that the Hadley cell transports, and the depth of the heat sink contained within the polar cell, ensures that transient weather phenomena not only have negligible effect on

3055-566: The rain to a temperature below freezing (0 °C or 32 °F). However, the drops themselves do not freeze, a phenomenon called supercooling (or forming " supercooled drops "). When the supercooled drops strike ground or anything else below 0 °C (32 °F) (e.g. power lines, tree branches, aircraft), a layer of ice accumulates as the cold water drips off, forming a slowly thickening film of ice, hence freezing rain. While meteorologists can predict when and where an ice storm will occur, some storms still occur with little or no warning. In

3120-550: The request of the Province of Quebec, CF members assumed the powers of peace officers in the most devastated areas around Montreal. At the height of this crisis, Operation Recuperation involved 15,784 deployed personnel (including 3,740 Reservists) from all three CF commands: 10,550 in Quebec, 4,850 in Ontario and 384 in New Brunswick. In addition, 6,200 CF members and DND employees working at their regular jobs provided

3185-400: The rest were damaged to different degrees and had to be trimmed, a large number severely. Critically, about 1,000 steel electrical pylons and 35,000 wooden utility poles were pulled over by the weight of the ice, further damaging the power supply and hampering the return of electricity. Teams were brought in from places such as Prince Edward Island and Nova Scotia , along with teams from

3250-472: The sick, shelter and feed about 100,000 people frozen out of their homes, and ensure that farmers had the generators and fuel required to keep their operations going. CP-140 aircraft from 14 Wing Greenwood, NS , conducted aerial imagery of the downed power lines in Quebec and Ontario. Military engineers and technicians worked around the clock with hydro and telephone crews to repair and replace downed transmission towers and utility poles. On January 13, at

3315-766: The south, southern Ontario and western New York, as well as much of the Appalachian region from Tennessee northward, received heavy rain and severe flooding, while further east, the Canadian Maritimes mostly received heavy snow. Exacerbating the problem was a steep drop in temperature that immediately followed the passage of the freezing rain, which combined with the extreme power outages led to numerous indirect deaths due to carbon monoxide poisoning from generators and other sources as people desperately tried to remain warm. Many power lines broke and over 1,000 transmission towers collapsed in chain reactions under

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3380-832: The surface. An unusually strong Bermuda high pressure area was anchored over the Atlantic Ocean, which prevented these systems from moving further to the east, as most winter storms do when they pass over the Great Lakes–St. Lawrence region. A series of surface low pressure systems passed in this atmospheric circulation between January 5 and January 10, 1998. For more than 80 hours, steady freezing rain and drizzle fell over an area of several thousand square miles of Eastern Ontario , including Ottawa, Brockville , and Kingston , an extensive area in southern Quebec, northern New York , and northern New England (including parts of Vermont , New Hampshire and Maine ). Farther to

3445-404: The systems as a whole, but — except under unusual circumstances — they do not form. The endless chain of passing highs and lows which is part of everyday life for mid-latitude dwellers, under the Ferrel cell at latitudes between 30 and 60° latitude, is unknown above the 60th and below the 30th parallels. There are some notable exceptions to this rule; over Europe, unstable weather extends to at least

3510-552: The total lack of electricity for weeks. Cities such as Ottawa , Smiths Falls , and other Eastern Ontario municipalities, that had never experienced such an amount of freezing rain, declared a state of emergency. On January 7, Ontario, Quebec, and New Brunswick called on the help of the Canadian Forces , prompting the deployment of more than 15,000 military personnel at the peak of the crisis. In addition to help residents, CN locomotives (CN3502 and CN3555) were moved off

3575-449: The tracks and used to provide power to residents of Boucherville and Coteau-du-Lac , south and west of Montreal respectively. A third locomotive was moved to Boucherville, but never actually put to use. The loss of electrical power also greatly affected pig and cattle farmers, as they could no longer provide water or adequate ventilation to their barns full of livestock, leading to the death of many animals. Many barns also collapsed under

3640-548: The transitional zone between the tropopause and the Ferrel cell . By acting as a heat sink, the polar cell moves the abundant heat from the equator toward the polar regions. The polar cell, terrain, and katabatic winds in Antarctica can create very cold conditions at the surface, for instance the lowest temperature recorded on Earth : −89.2 °C at Vostok Station in Antarctica, measured in 1983. The Hadley cell and

3705-551: The tropopause, it cools and subsides in a region of relatively cooler water mass. The Pacific Ocean cell plays a particularly important role in Earth's weather. This entirely ocean-based cell comes about as the result of a marked difference in the surface temperatures of the western and eastern Pacific. Under ordinary circumstances, the western Pacific waters are warm, and the eastern waters are cool. The process begins when strong convective activity over equatorial East Asia and subsiding cool air off South America 's west coast create

3770-722: The upwelling of nutrient-rich deep water. This has serious impacts on the fish populations. In the La Niña case, the convective cell over the western Pacific strengthens inordinately, resulting in colder than normal winters in North America and a more robust cyclone season in South-East Asia and Eastern Australia . There is also an increased upwelling of deep cold ocean waters and more intense uprising of surface air near South America, resulting in increasing numbers of drought occurrences, although fishermen reap benefits from

3835-541: The use of alternative methods of heating and cooking during prolonged power outages, common after severe ice storms. Gas generators, charcoal and propane barbecues, and kerosene heaters contribute to CO poisoning when they operate in confined locations. CO is produced when appliances burn fuel without enough oxygen present, such as basements and other indoor locations. Loss of electricity during ice storms can indirectly lead to hypothermia and result in death. It can also lead to ruptured pipes due to water freezing inside

3900-486: The weather behaves as expected. But every few years, the winters become unusually warm or unusually cold, or the frequency of hurricanes increases or decreases, and the pattern sets in for an indeterminate period. The Walker Cell plays a key role in this and in the El Niño phenomenon. If convective activity slows in the Western Pacific for some reason (this reason is not currently known), the climates of areas adjacent to

3965-564: The weight of ice. Falling branches can block roads, tear down power and telephone lines, and cause other damage. Even without falling trees and tree branches, the weight of the ice itself can easily snap power lines and also break and bring down power/utility poles; even electricity pylons with steel frames. This can leave people without power for anywhere from several days to a month. According to most meteorologists , just 0.25-inch (6.4 mm) of ice accumulation can add about 500 pounds (230 kg) of weight per line span. Damage from ice storms

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4030-460: The weight of the ice, killing the animals trapped inside. Millions of trees were brought down by the weight of ice around the affected areas. With many trees damaged or felled by the heavy ice, the maple syrup and orchard regions suffered heavy blows and massive losses in the storm; Quebec's maple sugar industry, the largest in the world, was devastated. As another example, 5,000 trees in Montreal's Mount Royal Park had to be cut, 80% (140,000) of

4095-422: The weight of the ice, leaving more than 4 million people without electricity, most of them in southern Quebec , western New Brunswick and Eastern Ontario , some of them for an entire month. At least twenty-five people died in the areas affected by the ice, primarily from hypothermia , according to Environment Canada . Twelve more deaths and hundreds of millions of dollars in additional damage were caused by

4160-484: The west. Both of those deviations, as in the case of the Hadley and polar cells, are driven by conservation of angular momentum. As a result, just as the easterly Trade Winds are found below the Hadley cell, the Westerlies are found beneath the Ferrel cell. The Ferrel cell is weak, because it has neither a strong source of heat nor a strong sink, so the airflow and temperatures within it are variable. For this reason,

4225-487: Was the largest deployment of troops ever to serve on Canadian soil in response to a natural disaster since the Manitoba floods in 1997 , where 14,000 troops were deployed, and the largest operational deployment of Canadian military personnel since the Korean War . CF members from about 200 units across Canada helped provincial and municipal workers clear roads, rescue people and animals trapped by storm wreckage, evacuate

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