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Seasons

Seasons

Seasons on Earth are characterized by differences in temperature and the length of daylight. The four distinct seasonsspring, summer, autumn (or fall), and winterare found only in the temperate zones. These zones extend from 23.5 degrees North (and South) latitude to 66.5 degrees North (and South) latitude. The equatorial regions or torrid zones have no noticeable seasonal changes, only a wet season and a dry season. Polar regions experience only a light season and a dark season.

Spring comes from an Old English word meaning "to rise." Summer originated as a Sanskrit word meaning "half year" or "season." Autumn comes originally from a Etruscan word for "maturing." Winter comes from an Old English word meaning "wet" or "water."

In the Northern Hemisphere, astronomers assign an arbitrary starting date for each season. Spring begins around March 21, summer around June 22, autumn around September 23, and winter around December 22. In the Southern Hemisphere, the seasons are reversed with spring beginning in September, summer in December, fall in March, and winter in

June. Seasons in the Southern Hemisphere are generally milder because of the larger amounts of ocean surface in that hemisphere. Since oceans heat up and cool down much slower than landmasses, they exert a moderating force on temperatures.

Reason for the seasons

Earth makes one complete revolution about the Sun each year. Changes in the seasons are caused not by the varying distance between Earth and the Sun, but by the tilt of Earth on its axis during that revolution. (Earth's axis of rotation is tilted 23.5 degrees to the plane of its orbit.) As Earth orbits the Sun, there are times of the year when the North Pole is alternately tilted toward the Sun (during Northern Hemispheric summer) or tilted away from the Sun (during Northern Hemispheric winter). At other times the axis is generally parallel to the incoming Sun's rays.

Words to Know

Autumnal equinox: Date in the fall of the year when Earth experiences 12 hours of daylight and 12 hours of darkness, usually around September 23.

Summer solstice: Date on which the Sun is highest in the sky at noon in the Northern Hemisphere, usually around June 22.

Temperate zones: Two regions on Earth bounded by 23.5 degrees latitude and the 66.5 degrees latitude.

Torrid zone: Zone on Earth bounded by 23.5 degrees north and south latitude.

Vernal equinox: Date in the spring of the year when Earth experiences 12 hours of daylight and 12 hours of darkness, usually around March 21.

Winter solstice: Date on which the Sun's noontime height is at its lowest in the Northern Hemisphere, usually on December 22.

During summer, two effects contribute to produce warmer weather. First, the Sun's rays fall more directly on Earth's surface, producing a stronger heating effect. Second, daylight hours outnumber nighttime hours. The Sun's rays warm Earth during daylight hours and Earth cools at night by reradiating heat back into space. Since there are longer periods of daylight and shorter periods of darkness during the summer, Earth receives more solar heat then it releases back into space. Thus, areas experiencing summer stay warmer.

The equinox

When the axis of Earth is perfectly parallel to the incoming rays of the Sun in springaround March 21the Sun rises in a direction that is due east everywhere on Earth and stands directly over the equator at noon. As a result, daylight hours equal nighttime hours everywhere on Earth. This effect gives rise to the name given to this date, the vernal equinox. Vernal comes from the Latin word for "spring," while equinox is formed from the Latin word for "equal night." The corresponding date in the fall when 12 hours of daylight and 12 hours of darkness occur everywhere on Eartharound September 23is known as the autumnal equinox.

The solstice

After the vernal equinox, the Sun continues to move in a northward direction and rise a little farther north of east each day until around June 22. On this day, the Sun has reached its extreme northward position and seems to stand still in its noon height above the horizon. For this reason, the date is known as the summer solstice, from the Latin words meaning "sun stands still." The summer solstice, the longest day and shortest night of the year in the Northern Hemisphere, marks the beginning of summer in the Northern Hemisphere. Afterward, the Sun begins to move southward. It crosses the celestial equator (the autumnal equinox) and continues to move southward, rising a little farther south of east each day until it reaches its most extreme southward position around December 22the winter solstice (the shortest day and longest night in the Northern Hemisphere). Afterward, the Sun begins its northward movement back to the vernal equinox.

Celebrating the seasons

Early societies celebrated the changes in the seasons on some of these cardinal dates. The vernal equinox was a day of celebration for the early Celtic tribes in ancient England, France, and Ireland. Other northern European tribes also marked the return of warmer weather on this date. Even the winter solstice was a time to celebrate, as it marked the lengthening days that would lead to spring. The ancient Romans celebrated the Feast of Saturnalia on the winter solstice. And even though there are no historical records to support the choice of a late December date for the birth of Jesus of Nazareth, Christians in the fourth century a.d. chose to celebrate Jesus' birth on the winter solstice. In the Julian calendar system in use at that time, this date fell on December 25.

[See also Calendar; Global climate ]

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season

sea·son / ˈsēzən/ • n. each of the four divisions of the year (spring, summer, autumn, and winter) marked by particular weather patterns and daylight hours, resulting from the earth's changing position with regard to the sun. ∎  a period of the year characterized by a particular climatic feature or marked by a particular activity, event, or festivity: the rainy season the season for gathering pine needles. ∎  a fixed time in the year when a particular sport is played: basketball season is over. ∎  the time of year when a particular fruit, vegetable, or other food is plentiful and in good condition: the pies are made with fruit that is in season lobster season. ∎  an indefinite or unspecified period of time; a while: this most beautiful soul, who walked with me for a season in this world. ∎ archaic a proper or suitable time: to everything there is a season. • v. [tr.] 1. add salt, herbs, pepper, or other spices to (food): season the soup to taste with salt and pepper | [as adj.] (seasoned) seasoned flour. ∎  add a quality or feature to (something), esp. so as to make it more lively or exciting: his conversation is seasoned liberally with exclamation points and punch lines. 2. make (wood) suitable for use as timber by adjusting its moisture content to that of the environment in which it will be used: [as adj.] (seasoned) it was made from seasoned, untreated oak. ∎  [as adj.] (seasoned) accustomed to particular conditions; experienced: she is a seasoned traveler. PHRASES: for all seasons suitable in or appropriate for every kind of weather: a coat for all seasons. ∎  adaptable to any circumstance: a singer for all seasons. season's greetings used as an expression of goodwill at Christmas or the New Year.

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"season." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. 15 Dec. 2017 <http://www.encyclopedia.com>.

"season." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. (December 15, 2017). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/season-1

"season." The Oxford Pocket Dictionary of Current English. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/season-1

seasons

seasons, divisions of the year characterized by variations in the relative lengths of day and night and in the amount of heat received from the sun. These variations depend on the inclination of the equator to the plane of the ecliptic and on the revolution of the earth around the sun. The amount of heat received at a given point on the earth's surface depends chiefly on the angle at which the sun's rays strike the earth at that point and on the daily duration there of exposure to the sun's rays; the more vertical the rays and the longer the exposure, the more heat will be received. Seasonal change varies greatly with latitude. Near the equator there is little change; in high latitudes spring and autumn are very short. In the temperate zones there are four well-defined seasons; in the north temperate zone, spring begins about Mar. 21, the vernal equinox; summer, about June 22, the summer solstice; autumn, about Sept. 23, the fall equinox; and winter, about Dec. 22, the winter solstice. However, the weather lags somewhat behind the seasons because, at the time of maximum sunlight (summer solstice for the Northern Hemisphere) the ground is still too cold to radiate as much heat as it receives, so average temperatures usually continue to rise for several weeks until a balance is reached between reception and radiation of heat. In low latitudes and in certain other areas (e.g., India) where oceans and winds are the chief factors governing seasonal changes, the terms "wet season" and "dry season" are used. The seasons play an important part in mythology and folklore; many holidays are connected with the changes of season.

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"seasons." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. 15 Dec. 2017 <http://www.encyclopedia.com>.

"seasons." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (December 15, 2017). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/seasons

"seasons." The Columbia Encyclopedia, 6th ed.. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/seasons

season

season (appropriate) time or period XIII; period of the year (spring, summer, autumn, winter); time of breeding, etc. XIV. ME. seson, -(o)un — OF. seson (mod. saison) :- L. satiō, -ōn- sowing, in Rom. time of sowing, seed-time, f. IE. *sə-, as in L. satus sown (cf. SOW2)
So season vb. render more palatable by the addition of a spice, salt, etc. XIV; bring to maturity XVI. — OF. saisonner (repl. by mod. assaisonner). Hence seasonable, seasonably XIV, seasonal XIX. seasoning †impregnation; savoury addition to a dish. XVI. The sense-development in the vb., as shown in Rom. dialects, is presumed to have been: ‘sow’, ‘cultivate at a favourable time’, ‘ripen, mature’, ‘cook well’, ‘add flavouring to’.

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"season." The Concise Oxford Dictionary of English Etymology. . Encyclopedia.com. 15 Dec. 2017 <http://www.encyclopedia.com>.

"season." The Concise Oxford Dictionary of English Etymology. . Encyclopedia.com. (December 15, 2017). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/season-2

"season." The Concise Oxford Dictionary of English Etymology. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/season-2

seasons

seasons Four periods of the year based on differential solar heating of the Earth as it makes its annual revolution of the Sun. The Northern Hemisphere receives more solar radiation when its Pole points towards the Sun in summer and less in winter when it points away. The opposite holds for the Southern Hemisphere. The seasons begin at the vernal (spring) and autumnal equinoxes and the winter and summer solstices.

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"seasons." World Encyclopedia. . Encyclopedia.com. 15 Dec. 2017 <http://www.encyclopedia.com>.

"seasons." World Encyclopedia. . Encyclopedia.com. (December 15, 2017). http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/seasons

"seasons." World Encyclopedia. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/seasons

season

seasonItalian, stallion •cañon, canyon, companion •hellion, rebellion •Kenyan •Melanesian, Micronesian, Polynesian •billion, jillion, million, modillion, multimillion, pillion, septillion, sextillion, squillion, trillion, zillion •minion, opinion, pinion •carillon • slumgullion •bunion, Bunyan, grunion, onion, Runyon •roentgen • damson • Kansan • Tarzan •blazon, brazen, emblazon, liaison, raisin •Spätlesen •reason, season, treason •arisen, grison, imprison, mizzen, prison, risen, uprisen •Pilsen • crimson • malison •benison, denizen •orison • citizen •bedizen, greisen, horizon, kaizen •Stockhausen •chosen, frozen •Lederhosen • poison • Susan •cousin, cozen, dozen •Amazon

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"season." Oxford Dictionary of Rhymes. . Encyclopedia.com. 15 Dec. 2017 <http://www.encyclopedia.com>.

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"season." Oxford Dictionary of Rhymes. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/season-0