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Winter

2007 Schools Wikipedia Selection. Related subjects: Climate and the Weather

                                                          CAPTION: Seasons

                                                                  Tropical

                                                                Dry season

                                                                Wet season

                                                          CAPTION: Seasons

                                                                 Temperate

                                                                    Spring

                                                                    Summer

                                                                    Autumn

                                                                    Winter

   Winter is one of the four seasons of temperate zones. It is the season
   with the shortest days and the lowest temperatures. In areas further
   away from the equator, winter is often marked by snow.

   Depending on place and culture, what is considered to be the start and
   end of winter vary. Contemporary meteorology takes winter to be the
   months of December, January, and February in the Northern Hemisphere
   and June, July, and August in the Southern Hemisphere. However, many
   cultures in Europe and East Asia consider winter to begin in November.
   In many parts of the world, winter is associated with snow and ice.
   Winter in Germany (above).
   Enlarge
   In many parts of the world, winter is associated with snow and ice.
   Winter in Germany (above).

Meteorological aspects

   Animation of snowcover changing with the seasons.
   Enlarge
   Animation of snowcover changing with the seasons.

   Meteorological winter is the season having the shortest days (which
   vary greatly according to latitude) and the lowest temperatures.
   Nighttime predominates the winter season, and in some regions it has
   the highest rate of precipitation as well as prolonged dampness due to
   permanent snow cover in such areas. Measured astronomically, winter
   begins on the shortest day of the year, and each day of winter has more
   sunlight than the previous one.

   Outside the equatorial areas, winter is cold and (particularly in the
   Northern Hemisphere) snowy. Blizzards often develop and cause many
   transportation delays. A rare meteorological phenomenon encountered
   during winter is ice fog, which is composed of ice crystals suspended
   in the air and happening only at very low temperatures, below about −30
   °C .

Time period of winter

   Astronomically, it starts with the winter solstice (around December 21
   in the Northern Hemisphere and June 21 in the Southern Hemisphere), and
   ends with the spring equinox (around March 21 in the Northern
   Hemisphere and September 21 in the Southern Hemisphere). In
   meteorology, it is by convention counted instead as the whole months of
   June, July and August in the Southern Hemisphere and December, January
   and February in the Northern Hemisphere.

   However, in the United Kingdom and Ireland the winter solstice is
   traditionally considered as midwinter, the winter season beginning
   November 1 on All Hallows or Samhain. Winter ends and spring begins on
   Imbolc or Candlemas, which is February 1 or 2. This system of seasons
   is based on the length of days exclusively. The three-month period of
   the shortest days and weakest solar radiation occurs during November,
   December and January in the Northern Hemisphere (May-July in the
   Southern).

   In Chinese astronomy (and other East Asian calendars), winter is taken
   to commence on or around November 7, with the Jiéqì known as (立冬 lì
   dōng, literally "establishment of winter".)

   In reality, the three-month period associated with the coldest average
   temperatures typically begins somewhere in late November or early
   December in the Northern Hemisphere. If "winter" is defined as the
   statistically coldest quarter of the year, then the astronomical
   definition is too late by almost all local climate standards, and the
   traditional English/Irish definition of November 1 (May 1 in the
   Southern Hemisphere) is almost always too early to fit this standard.
   No matter the recogning, winter is the only season that spans two
   calendar years in the northern hemisphere. (In other words, there are
   very few temperate climates in which the vernal equinox is on average
   colder than the winter solstice, and very few temperate climates in
   which Samhain is colder than Imbolc)

What causes winter

   Illumination of Earth by Sun in the northern hemisphere winter
   Enlarge
   Illumination of Earth by Sun in the northern hemisphere winter

   The tilt of the earth's axis relative to its orbital plane has a
   dramatic effect on the weather. The popular belief that winter is
   caused by the Earth being farther from the Sun than in summer is not
   true. In fact, in the Northern Hemisphere, winter occurs when the Earth
   is its closest to the Sun.

   The earth is tilted at an angle of 23°27' (23 degrees 27 minutes) to
   the plane of its orbit, and this causes different latitudes on the
   Earth to directly face the Sun as the Earth moves through its orbit. It
   is this variation that primarily brings about the seasons. When it is
   winter in the Northern Hemisphere, the Southern Hemisphere faces the
   Sun more directly and thus experiences warmer temperatures than the
   Northern Hemisphere.

   During winter in either hemisphere, sunlight hits that hemisphere at an
   oblique angle. In regions experiencing winter, the same amount of solar
   radiation is spread out over a larger area (see Effect of sun angle on
   climate). This effect is compounded by the larger distance that the
   light must travel through the atmosphere, allowing the atmosphere to
   dissipate more of this already limited heat.

Ecology

   The Snowshoe Hare is one animal that changes color in winter
   Enlarge
   The Snowshoe Hare is one animal that changes colour in winter

Animals

   To survive the harshness of winter, many animals have developed
   different behavioural and morphological adaptations:
     * Migration is a common effect of winter upon animals, notably birds.
       However some birds, the cardinal for example, do not migrate.
     * Hibernation is a state of reduced metabolic activity during the
       winter. These animals "sleep" during winter and only come out as
       warm weather returns. For example, gophers, bears, frogs, snakes
       and bats hibernate.
     * Some animals store food for the winter and live upon it instead of
       hibernating completely. This is the case of squirrels, beavers,
       skunks, badgers and raccoons.
     * Resistance is observed when an animal endures winter, but changes
       in ways such as colour and musculature. The colour of the fur or
       plumage are changed to white in order to be confused with snow and
       thus, to retain their cryptic coloration year round. Examples are
       the ptarmigan, the arctic fox, the weasel, the white-tailed jack
       rabbit or the mountain hare.
     * Some fur-coated mammals grow a heavier fur coat during the winter.
       This improves the heat-retention qualities of the fur. The coat is
       then shed following the winter season to allow better cooling. The
       heavier winter coat made this season a favorite for trappers who
       sought more profitable skins.
     * Snow also affects the ways animals behave, as many take advantage
       of the insulating properties of snow by burrowing in it. Mice and
       voles typically live under the snow layer.

Plants

   Annual plants never survive the winter. As for perennial plants, many
   small ones profit from the insulating effects of snow by being buried
   in it. Larger plants, particularly deciduous trees, usually let their
   upper part die, but their roots are still protected by the snow layer.
   Few plants bloom in the winter, though exceptions include the flowering
   apricot (which flowers in time for Chinese New Year).

Activities

   Snowboarder in the halfpipe
   Enlarge
   Snowboarder in the halfpipe

Snow activities

     * Bobsledding - a winter sport in which teams make timed runs down
       narrow, twisting, banked purpose-built iced tracks in a
       gravity-powered, steerable sled.
     * Skiing - the activity of gliding over snow using what is now
       fibreglass planks called skis that are strapped to the skiers' feet
       with ski bindings.

     * Sledding - a downhill activity where the user uses a sled to glide
       down the hill.
     * Snowball fight - a physical game in which snowballs are thrown with
       the intention of hitting someone else.
     * Snowboarding - an increasingly common sport where participants
       strap a composite board to their feet and slide down a snow-covered
       mountain.
     * Snowshoeing - a means of travel in which one is able to walk on top
       of the snow by increasing the surface area of their feet.
     * Snowman building - creating a man-like model out of snow.
     * Building snow castles and other snow constructions - The SnowCastle
       of Kemi is the largest one in the world.

Ice activities

     * Ice skating - a means of traveling on ice with skates, narrow (and
       sometimes parabolic) blade-like devices moulded into special boots
       (or, more primitively, without boots, tied to regular footwear).
     * Ice boating - a means of travel in a specialized boat similar in
       appearance to a sailboat but fitted with skis or runners (skates)
       and designed to run over ice instead of (liquid) water.
     * Ice biking - The continuation of regular cycling activities in the
       winter and cold weather.
     * Ice fishing - the sport of catching fish with lines and hooks
       through an opening in the ice on a frozen body of water.
     * Ice diving - a type of penetration diving where the dive takes
       place under ice.
     * Ice sculpture - elaborate sculptures are carved out of blocks of
       ice.
     * Ice Hockey - A team sport played on the ice with skates, sticks and
       a puck. The goal is to send the puck in the adverary team's net
       more often than they send it in yours during 60 minutes of play.
     * Curling - A team sport using skates, brooms and stones. The object
       of the game is to slide your stones in a bullseye and get your
       opponent's stones out of it.
     * Ice climbing - The recreational activity of climbing ice formations
       such as icefalls, and great frozen waterfalls.

Psychology

   Long, harsh winters are believed to have affected the Russian national
   character.
   Enlarge
   Long, harsh winters are believed to have affected the Russian national
   character.

   Passing seasons change the habits and moods of people. Around November
   and December in the northern hemisphere, a gloominess nicknamed "winter
   blues", "February blahs", "Holiday depression", or doldrums, is
   informally noted amongst people. The severest cases of this type of
   depression is diagnosed as seasonal affective disorder (SAD). Symptoms
   include sleeping more, tiredness, depression, and physical aches.
   Although causes include genetic disposition and stress, the prevailing
   environmental influence is decreased exposure to light due to winter
   weather patterns and the increased amount of clothing that must be worn
   to keep warm.

The symbolism of winter

   Winter is highly symbolic of many things to many people and has been
   used to represent various things by artists in all media. Some use
   winter to suggest death, as in Robert Frost's " Stopping by Woods on a
   Snowy Evening". Some use it to suggest the absence of hope, as in C. S.
   Lewis's The Lion, the Witch and the Wardrobe, where it was always
   winter but never Christmas. Winter is one concerto in Vivaldi's "The
   Four Seasons"; and there are many examples of four paintings, all
   showing the same scene in different seasons. Ursula K. LeGuin's novel
   The Left Hand of Darkness is set on a planet named Winter. In Alex
   Raymond's comic strip, Flash Gordon, there is a land called Frigia,
   where it is always winter. The land of Frigia is also featured in the
   serial Flash Gordon Conquers the Universe. Other uses of winter in the
   graphic arts occur in Winsor McCay's Little Nemo in Slumberland. There
   are many films in which a winter setting plays an important role, Fargo
   being an example. In addition to this, novels such as Ethan Frome also
   use a winter setting to mirror the bleak, frozen feelings that the
   characters harbour.

Mythological explanations of winter

   In Greek mythology, Hades kidnapped Persephone to be his wife. Zeus
   ordered Hades to return her to Demeter, the goddess of the earth and
   her mother. However, Hades tricked Persephone into eating the food of
   the dead so Zeus decreed Persephone would spend six months with Demeter
   and six months with Hades. During the time when her daughter is with
   Hades, Demeter becomes depressed and causes winter.

Personifications of winter

     * Old Man Winter
     * Father Winter
     * Jack Frost
     * Ded Moroz
     * Snegurochka

   An allegory of Winter, by Ambrogio Lorenzetti

   Winter, by Giuseppe Arcimboldo

   19th century cartoon of Jack Frost as a United States major-general
   during the American Civil War

   Roman mosaic of the four seasons. Winter is at the lower right corner.

   A depiction of Snegurochka by Victor Vasnetsov

Exceptional winters

     * 1816 is considered the " Year Without a Summer" because the summer
       was so cold that it was like winter lasted all year.
     * Russian Winters of 1812/13 and 1941/42
     * In Europe, the winters of 1962/63 and 1981/82 were abnormally cold.
     * The Winter of Discontent is the name for the British winter of
       1978-79, during which there were widespread strikes. Lorry drivers,
       train drivers, nurses, most public sector employees, refuse
       collectors, and workers at Ford Motors all went on strike. Most
       notorious however was an unofficial strike by gravediggers.

   Retrieved from " http://en.wikipedia.org/wiki/Winter"
   This reference article is mainly selected from the English Wikipedia
   with only minor checks and changes (see www.wikipedia.org for details
   of authors and sources) and is available under the GNU Free
   Documentation License. See also our Disclaimer.
