Nor'easter

A powerful nor'easter in March 2014

A nor'easter (also northeaster; see below) is a macro-scale cyclone. The name derives from the direction of the strongest winds—as an offshore air mass rotates counterclockwise, winds tend to blow northeast-to-southwest over the region covered by the northwest quadrant of the cyclone. Use of the term in North America is associated with several different types of storms, some of which can form in the North Atlantic Ocean and some of which form as far south as the Gulf of Mexico. The term is most often used in the coastal areas of New England and the Mid-Atlantic states. Typically, such storms originate as a low-pressure area that forms within 100 miles (160 km) of the shore between North Carolina and Massachusetts. The precipitation pattern is similar to that of other extratropical storms. Nor’easters are usually accompanied by very heavy rain or snow, and can cause severe coastal flooding, coastal erosion, hurricane-force winds, or blizzard conditions. Nor'easters are usually most intense during winter in New England and Atlantic Canada. They thrive on converging air masses—the cold polar air mass and the warmer air over the water—and are more severe in winter when the difference in temperature between these air masses is greater.[1][2][3]

Nor'easters tend to develop most often and most powerfully between the months of November and March, although they can (much less commonly) develop during other parts of the year as well. The susceptible regions are generally impacted by Nor'easters a few times each winter.[4][5][6]

Etymology and usage

Compass card (1607)

The term nor'easter came to American English by way of British English. According to the Oxford English Dictionary, the first recorded use in the English language of the term "nore" (“north”) in association with the points of the compass and wind direction was by Dekker in 1612: "How blowes the winde Syr?" "Wynde! is Nore-Nore-West." However, this is incorrect, as John Lyly uses the term the same way in his play of 1585, Gallathea.

Similar uses occurred in 1688 (… Nore and Nore-West …) and in 1718 (… Nore-west or Nore-nore-west.) These recorded uses are predated by use of the term "noreast", first recorded as used by Davis in 1594 (Noreast by North raiseth a degree in sayling 24 leagues.) and shown, for instance, on a compass card published in 1607. Thus, the manner of pronouncing from memory the 32 points of the compass, known in maritime training as "boxing the compass", is described by Ansted[7] with pronunciations "Nor'east (or west)," "Nor' Nor'-east (or west)," "Nor'east b' east (or west)," and so forth. According to the OED, the first recorded use of the term "nor'easter" occurs in 1836 in a translation of Aristophanes. The term “nor’easter” naturally developed from the historical spellings and pronunciations of the compass points and the direction of wind or sailing.

As noted in a January 2006 editorial by William Sisson, editor of Soundings magazine,[8] use of "nor'easter" to describe the storm system is common along the U.S. East Coast. Yet it has been asserted by linguist Mark Liberman (see below) that "nor'easter" as a contraction for "northeaster" has no basis in regional New England dialect; the Boston accent would elide the "R": no'theastuh'. He describes nor'easter as a "fake" word. However, this view neglects the little-known etymology and the historical maritime usage described above.

Nineteenth-century Downeast mariners pronounced the compass point "north northeast" as "no'nuth-east", and so on. For decades, Edgar Comee, of Brunswick, Maine, waged a determined battle against use of the term "nor'easter" by the press, which usage he considered "a pretentious and altogether lamentable affectation" and "the odious, even loathsome, practice of landlubbers who would be seen as salty as the sea itself". His efforts, which included mailing hundreds of postcards, were profiled, just before his death at the age of 88, in The New Yorker.[9]

Despite the efforts of Comee and others, use of the term continues by the press. According to Boston Globe writer Jan Freeman, "from 1975 to 1980, journalists used the nor’easter spelling only once in five mentions of such storms; in the past year (2003), more than 80 percent of northeasters were spelled nor'easter".[10]

University of Pennsylvania linguistics professor Mark Liberman has pointed out that while the Oxford English Dictionary cites examples dating back to 1837, these examples represent the contributions of a handful of non-New England poets and writers. Liberman posits that "nor'Easter" may have originally been a literary affectation, akin to "e'en" for "even" and "th'only" for "the only", which is an indication in spelling that two syllables count for only one position in metered verse, with no implications for actual pronunciation.[11]

However, despite these assertions, the term can be found in the writings of New Englanders, and was frequently used by the press in the 19th century.

Usage existed into the 20th century in the form of:

Geography and formation characteristics

Surface temperature of the sea off the east coast of North America. The corridor in yellow gives the position of the Gulf Stream

Formation

Nor'easters develop in response to the sharp contrast in the warm Gulf Stream ocean current coming up from the tropical Atlantic and the cold air masses coming down from Canada. When the very cold and dry air rushes southward and meets up with the warm Gulf stream current, which is often near 70 °F (21 °C) even in mid-winter, intense low pressure develops.

In the upper atmosphere, the strong winds of the jet stream remove and replace rising air from the Atlantic more rapidly than the Atlantic air is replaced at lower levels; this and the Coriolis force help develop a strong storm. The storm tracks northeast along the East Coast past the Carolinas, the mid-Atlantic, and the New England coastal states. Counterclockwise winds around the low-pressure system blow the moist air over land. The relatively warm, moist air meets cold air coming southward from Canada. The low increases the surrounding pressure difference, which causes the very different air masses to collide at a faster speed. When the difference in temperature of the air masses is larger, so is the storm's instability, turbulence, and thus severity.[1][19]

The nor'easters taking the East Coast track usually indicates the presence of a high-pressure area in the vicinity of Nova Scotia.[20] Sometimes a nor'easter will move slightly inland and bring rain to the cities on the coastal plain (New York City, Philadelphia, Baltimore, etc.) and snow in New England (Boston northward). It can move slightly offshore, bringing a wet snow south of Boston to Richmond, Virginia, or even parts of the Carolinas.[21] Such a storm will rapidly intensify, tracking northward and following the topography of the East Coast, sometimes continuing to grow stronger during its entire existence. A nor'easter usually reaches its peak intensity while off the Canadian coast. The storm then reaches Arctic areas, and can reach intensities equal to that of a weak hurricane. It then meanders throughout the North Atlantic and can last for several weeks.[21]

Characteristics

Nor'easters are usually formed by an area of vorticity associated with an upper-level disturbance or from a kink in a frontal surface that causes a surface low-pressure area to develop. Such storms are very often formed from the merging of several weaker storms, a "parent storm", and a polar jet stream mixing with the tropical jet stream.

Until the nor'easter passes, thick, dark, low-level clouds often block out the sun. Temperatures usually fall significantly due to the presence of the cooler air from winds that typically come from a northeasterly direction. During a single storm, the precipitation can range from a torrential downpour to a fine mist. All precipitation types can occur in a nor'easter. High wind gusts, which can reach hurricane strength, are also associated with a nor'easter. On very rare occasions, such as in the North American blizzard of 2006 and a nor'easter in 1978, the center of the storm can take on the circular shape more typical of a hurricane and have a small "dry slot" near the center, which can be mistaken for an eye, although it is not an eye.

Difference from tropical cyclones

Often, people mistake nor'easters for tropical cyclones and do not differentiate between the two weather systems. Nor'easters differ from tropical cyclones in that nor'easters are cold-core low-pressure systems, meaning that they thrive on cold air. Tropical cyclones are warm-core low-pressure systems, which means they thrive on warm temperatures.

Difference from other extratropical storms

A nor'easter is formed in a strong extratropical cyclone, usually experiencing bombogenesis. While this formation occurs in many places around the world, nor'easters are unique for their combination of northeast winds and moisture content of the swirling clouds. Nearly similar conditions sometimes occur during winter in the Pacific Northeast (northern Japan and northwards) with winds from NW-N. In Europe, similar weather systems with such severity are hardly possible; the moisture content of the clouds is usually not high enough to cause flooding or heavy snow, though NE winds can be strong.

Geography

The eastern United States, from North Carolina to Maine, and Eastern Canada can experience nor'easters, though most often they affect the areas from northern New Jersey northward. The effects of a nor'easter sometimes bring high tides and strong winds as far south as coastal South Carolina and Georgia. Surfers wait in anticipation when a nor’easter is formed. Nor’easters cause a significant amount of beach erosion in these areas, as well as flooding in the associated low-lying areas.

Biologists at the Woods Hole Oceanographic Institution on Cape Cod have determined nor’easters are an environmental factor for red tides of the Atlantic coast.

Notable nor’easters

Here is a list of notable nor’easters, followed by a short description about the event.

See also

References

  1. 1 2 Multi-Community Environmental Storm Observatory (2006). "Nor'easters". Multi-community Environmental Storm Observatory. Archived from the original on October 9, 2007.
  2. "Know the dangers of nor’easters". National Oceanic and Atmospheric Administration. Archived from the original on February 14, 2016.
  3. How stuff works (2006). "What are nor'easters?". Retrieved January 22, 2008.
  4. "National Weather Service". National Weather Service. National Oceanic and Atmospheric Administration. Retrieved 29 Feb 2016.
  5. "AccuWeather.com".
  6. L. Dove, Laurie. "What's a nor'easter?".
  7. Ansted. A Dictionary of Sea Terms, Brown Son & Ferguson, Glasgow, 1933
  8. "Featuring Boating News, Stories and More". Soundings Online. Retrieved 2012-08-18.
  9. McGrath, Ben (September 5, 2005). "Nor’Easter". The New Yorker: Tsk-Tsk Dept. Condé Nast. Retrieved June 3, 2013.
  10. Freeman, Jan (December 21, 2003). "Guys and dolls". Boston Globe: The Word. The New York Times Company. Retrieved June 3, 2013.
  11. Liberman, Mark (January 25, 2004). "Nor’Easter Considered Fake". Language Log. Retrieved June 3, 2013.
  12. "Snow Storm", The Hartford Times, Hartford, 28 December 1836
  13. Thomas Bailey Aldrich (1911). The Story of a Bad Boy. Houghton, Mifflin. Retrieved 19 May 2013.
  14. Charles Dudley Warner (1896). Library of the World's Best Literature. Retrieved 2013-10-10.
  15. John H. Tice (1878). A new system of meteorology, designed for schools and private students: Descriptive and explanatory of all the facts, and demonstrative of all the causes and laws of atmospheric phenomena. Tice & Lillingston. Retrieved 19 May 2013.
  16. Charities and the Commons: A Weekly Journal of Philanthropy and Social Advance. Publication Committee of the New York Charity Organization Society. 1908. p. unknown. Retrieved 19 May 2013.
  17. Mary Rogers Bangs (1920). Old Cape Cod: The Land, the Men, the Sea. Houghton Mifflin. pp. 182–. Retrieved 19 May 2013.
  18. Ralph E. Huschke (1959). Glossary of Meteorology. American Meteorological Soc. Retrieved 19 May 2013.
  19. Storm-E (2007). "Nor'easters". Retrieved January 22, 2008.
  20. The Weather Channel (2007). "Nor'easters". The Weather Channel. Retrieved January 24, 2016.
  21. 1 2 Multi-Community Environmental Storm Observatory (2006). "Nor'easters". Archived from the original on October 9, 2007. Retrieved January 22, 2008.

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