Southern Hemisphere

The Southern Hemisphere is the half of Earth that is south of the Equator. It contains all or parts of five continents[1] (Antarctica, Australia, about 90% of South America, a third of Africa, and several islands off the continental mainland of Asia), four oceans (Indian, South Atlantic, Southern, and South Pacific) and most of the Pacific Islands in Oceania. Its surface is 80.9% water, compared with 60.7% water in the case of the Northern Hemisphere, and it contains 32.7% of Earth's land.[2]

Owing to the tilt of Earth's rotation relative to the Sun and the ecliptic plane, summer is from December to March and winter is from June to September. September 22 or 23 is the vernal equinox and March 20 or 21 is the autumnal equinox. The South Pole is in the center of the southern hemispherical region.

Southern Hemisphere LamAz
The Southern Hemisphere from above the South Pole
Global hemispheres
The Southern Hemisphere highlighted in yellow. The hemispheres appear to be unequal in this image due to Antarctica not being shown, but in reality are the same size.

Characteristics

Southern Hemisphere climates tend to be slightly milder than those at similar latitudes in the Northern Hemisphere, except in the Antarctic which is colder than the Arctic. This is because the Southern Hemisphere has significantly more ocean and much less land; water heats up and cools down more slowly than land.[3] The differences are also attributed to oceanic heat transfer (OHT) and differing extents of greenhouse trapping.[4]

Aurora australis panorama
Aurora australis appearing in the night sky of Swifts Creek, 100 km (62 mi) north of Lakes Entrance, Victoria, Australia
AuroraAustralisDisplay
Aurora australis appearing from Stewart Island / Rakiura in the south of New Zealand

In the Southern Hemisphere the sun passes from east to west through the north, although north of the Tropic of Capricorn the mean sun can be directly overhead or due north at midday. The Sun rotating through the north causes an apparent right-left trajectory through the sky unlike the left-right motion of the Sun when seen from the Northern Hemisphere as it passes through the southern sky. Sun-cast shadows turn anticlockwise throughout the day and sundials have the hours increasing in the anticlockwise direction. During solar eclipses viewed from a point to the south of the Tropic of Capricorn, the Moon moves from left to right on the disc of the Sun (see, for example, photos with timings of the solar eclipse of November 13, 2012), while viewed from a point to the north of the Tropic of Cancer (i.e., in the Northern Hemisphere), the Moon moves from right to left during solar eclipses.

Cyclones and tropical storms spin clockwise in the Southern Hemisphere (as opposed to anticlockwise in the Northern Hemisphere) due to the Coriolis effect.[5]

The southern temperate zone, a subsection of the Southern Hemisphere, is nearly all oceanic. This zone includes the southern tip of Uruguay and South Africa; the southern half of Chile and Argentina; parts of Australia, going south from Adelaide, and all of New Zealand.

The Sagittarius constellation that includes the galactic centre is a southern constellation and this, combined with clearer skies, makes for excellent viewing of the night sky from the Southern Hemisphere with brighter and more numerous stars.

Forests in the Southern Hemisphere have special features which set them apart from those in the Northern Hemisphere. Both Chile and Australia share, for example, unique beech species or Nothofagus, and New Zealand has members of the closely related genera Lophozonia and Fuscospora. The eucalyptus is native to Australia but is now also planted in Southern Africa and Latin America for pulp production and, increasingly, biofuel uses.

Demographics and human geography

Apollo17WorldReversed
A photo of Earth from Apollo 17 (Blue Marble) originally had the south pole at the top; however, it was turned upside-down to fit the traditional perspective

Approximately 800 million humans live in the Southern Hemisphere, representing only 10–12% of the total global human population of 7.3 billion.[6][7] Of those 800 million people, 200 million live in Brazil, the largest country by land area in the Southern Hemisphere, while 141 million live on the island of Java, the most populous island in the world. The most populous nation in the Southern Hemisphere is Indonesia, with 261 million people (roughly 30 million of whom live north of the equator on the northern portions of the islands of Sumatra, Borneo and Sulawesi, while the rest of the population lives in the Southern Hemisphere). Portuguese is the most spoken language in the Southern Hemisphere,[8] followed by Spanish and Javanese.

The largest metropolitan areas in the Southern Hemisphere are São Paulo (21 million people), Jakarta (18 million people), Buenos Aires (12 million people), Rio de Janeiro (11 million people), Kinshasa (11 million people) and Sydney (6 million) . The most important financial and commercial centers in the Southern Hemisphere are São Paulo, where the Bovespa Index is headquartered, along with Sydney, home to the Australian Securities Exchange, Johannesburg, home to the Johannesburg Stock Exchange and Buenos Aires, headquarters of the Buenos Aires Stock Exchange, the oldest stock market in the Southern Hemisphere.

Among the most developed nations in the Southern Hemisphere are Australia, with a nominal GDP per capita of US$51,850 and a Human Development Index of 0.939, the second highest in the world as of 2016. New Zealand is also well developed, with a nominal GDP per capita of US$38,385 and a Human Development Index of 0.915, putting it at #13 in the world in 2016. The least developed nations in the Southern Hemisphere cluster in Africa and Oceania, with Burundi and Mozambique at the lowest ends of the Human Development Index, at 0.404 (#184 in the world) and 0.418 (#181 in the world) respectively. The nominal GDP per capitas of these two countries don't go above US$550 per capita, a tiny fraction of the incomes enjoyed by Australians and New Zealanders.

The most widespread religions in the Southern Hemisphere are Christianity in South America, southern Africa and Australia/New Zealand, followed by Islam in most of the islands of Indonesia and in parts of southeastern Africa, and Hinduism, which is mostly concentrated on the island of Bali and neighboring islands.

The oldest continuously inhabited city in the Southern Hemisphere is Bogor, in western Java, which was founded in 669 CE. Ancient texts from the Hindu kingdoms prevalent in the area definitively record 669 CE as the year when Bogor was founded. However, there is some evidence that Zanzibar, an ancient port with around 200,000 inhabitants on the coast of Tanzania, may be older than Bogor. A Greco-Roman text written between 1 CE and 100 CE, the Periplus of the Erythraean Sea, mentioned the island of Menuthias (Ancient Greek: Μενουθιάς) as a trading port on the east African coast, which is probably the small island of Unguja on which Zanzibar is located. The oldest monumental civilizations in the Southern Hemisphere are the Norte Chico civilization and Casma–Sechin culture from the northern coast of Peru. These civilizations built cities, pyramids and plazas in the coastal river valleys of Northern Peru with some ruins dated back to 3600 BCE.

List of continents and countries

Continents and microcontinents

Countries and territories

Africa
Entirely
Mostly
Partially
Asia
Entirely
Mostly
Partially
Australia
Entirely
South America
Entirely
Mostly
Partially
Indian Ocean
Entirely
South Atlantic Ocean
Entirely
Southern Ocean
Entirely
South Pacific Ocean
Entirely
Mostly

References

  1. ^ "Hemisphere Map". WorldAtlas. Retrieved 13 June 2014.
  2. ^ Life on Earth: A - G.. 1. ABC-CLIO. 2002. p. 528. ISBN 9781576072868. Retrieved 8 September 2016.
  3. ^ Granite specific heat = 0.79 and water = 4.18 J/g⋅K see Heat capacity#Table_of_specific_heat_capacities.
  4. ^ Kang, Sarah M.; Seager, Richard. "Croll Revisited: Why is the Northern Hemisphere Warmer than the Southern Hemisphere?" (PDF). Columbia University.
  5. ^ "Surface Ocean Currents". National Oceanic and Atmospheric Administration. Retrieved 13 June 2014.
  6. ^ "90% Of People Live In The Northern Hemisphere - Business Insider". Business Insider. 4 May 2012. Retrieved 10 November 2015.
  7. ^ "GIC - Article". galegroup.com. Retrieved 10 November 2015.
  8. ^ "Potencial Económico da Língua Portuguesa" (PDF). University of Coimbra.

Media related to Southern Hemisphere at Wikimedia Commons

2006–07 Southern Hemisphere tropical cyclone season

The 2006–07 Southern Hemisphere tropical cyclone season comprises three different basins. Their respective seasons are:

2006-07 South-West Indian Ocean cyclone season west of 90°E,

2006-07 Australian region cyclone season between 90°E and 160°E, and

2006-07 South Pacific cyclone season east of 160°E.

Autumn

Autumn, also known as fall in American English and sometimes in Canadian English, is one of the four temperate seasons. Autumn marks the transition from summer to winter, in September (Northern Hemisphere) or March (Southern Hemisphere), when the duration of daylight becomes noticeably shorter and the temperature cools considerably. One of its main features in temperate climates is the shedding of leaves from deciduous trees.

Some cultures regard the autumnal equinox as "mid-autumn", while others with a longer temperature lag treat it as the start of autumn. Meteorologists (and most of the temperate countries in the southern hemisphere) use a definition based on Gregorian calendar months, with autumn being September, October, and November in the northern hemisphere, and March, April, and May in the southern hemisphere.

In North America, autumn traditionally starts on September 21 and ends on December 21. It is considered to start with the September equinox (21 to 24 September) and end with the winter solstice (21 or 22 December). Popular culture in the United States associates Labor Day, the first Monday in September, as the end of summer and the start of autumn; certain summer traditions, such as wearing white, are discouraged after that date. As daytime and nighttime temperatures decrease, trees shed their leaves. In traditional East Asian solar term, autumn starts on or around 8 August and ends on or about 7 November. In Ireland, the autumn months according to the national meteorological service, Met Éireann, are September, October and November. However, according to the Irish Calendar, which is based on ancient Gaelic traditions, autumn lasts throughout the months of August, September and October, or possibly a few days later, depending on tradition. The names of the months in Manx Gaelic are similarly based on autumn covering August, September and October. In Argentina, Australia and New Zealand, autumn officially begins on 1 March and ends on 31 May.

June

June is the sixth month of the year in the Julian and Gregorian calendars, the second of four months to have a length of 30 days, and the third of five months to have a length of less than 31 days. June contains the summer solstice in the Northern Hemisphere, the day with the most daylight hours, and the winter solstice in the Southern Hemisphere, the day with the fewest daylight hours (excluding polar regions in both cases). June in the Northern Hemisphere is the seasonal equivalent to December in the Southern Hemisphere and vice versa. In the Northern Hemisphere, the beginning of the traditional astronomical summer is 21 June (meteorological summer begins on 1 June). In the Southern Hemisphere, meteorological winter begins on 1 June.At the start of June, the sun rises in the constellation of Taurus; at the end of June, the sun rises in the constellation of Gemini. However, due to the precession of the equinoxes, June begins with the sun in the astrological sign of Gemini, and ends with the sun in the astrological sign of Cancer.

List of Australian region cyclones before 1967

The following is a list of Australian region tropical cyclones in or before 1967.

List of Southern Hemisphere tropical cyclone seasons

The following articles contain lists of Southern Hemisphere tropical cyclone seasons:

South-West Indian Ocean tropical cyclone season

Australian region tropical cyclone season

South Pacific tropical cyclone season

South Atlantic tropical cyclone

List of dialects of English

The following is a list of dialects of English. Dialects are linguistic varieties which may differ in pronunciation, vocabulary, spelling and grammar. For the classification of varieties of English in terms of pronunciation only, see Regional accents of English.

Dialects can be defined as "sub-forms of languages which are, in general, mutually comprehensible." English speakers from different countries and regions use a variety of different accents (systems of pronunciation), as well as various localized words and grammatical constructions; many different dialects can be identified based on these factors. Dialects can be classified at broader or narrower levels: within a broad national or regional dialect, various more localized sub-dialects can be identified, and so on. The combination of differences in pronunciation and use of local words may make some English dialects almost unintelligible to speakers from other regions.

The major native dialects of English are often divided by linguists into three general categories: the British Isles dialects, those of North America, and those of Australasia. Dialects can be associated not only with place, but also with particular social groups. Within a given English-speaking country, there will often be a form of the language considered to be Standard English – the Standard Englishes of different countries differ, and each can itself be considered a dialect. Standard English is often associated with the more educated layers of society, as well as more formal registers.

British and American English are the reference norms for English as spoken, written, and taught in the rest of the world, excluding countries where English is spoken natively such as Australia, Canada, Ireland and New Zealand. In many former British Empire countries where English is not spoken natively, British English forms are closely followed, alongside numerous AmE usages which have become widespread throughout the English-speaking world. Conversely, in many countries historically influenced by the United States where English is not spoken natively, American English forms are closely followed. Many of these countries, while retaining strong BrE or AmE influences, have developed their own unique dialects, which include Indian English and Philippine English.

Chief among other native English dialects are Canadian English and Australian English, which rank third and fourth in the number of native speakers. For the most part, Canadian English, while featuring numerous British forms alongside indigenous Canadianisms, shares vocabulary, phonology and syntax with American English, leading many to recognize North American English as an organic grouping of dialects. Australian English likewise shares many American and British English usages alongside plentiful features unique to Australia, and retains a significantly higher degree of distinctiveness from both the larger varieties than does Canadian English. South African English, New Zealand English and the Hiberno-English of Ireland are also distinctive and rank fifth, sixth and seventh in the number of native speakers.

Martian dichotomy

The most conspicuous feature of Mars is a sharp contrast, known as the Martian dichotomy, between the Southern hemisphere and the Northern. The two hemispheres' geography differ in elevation by 1 to 3 km. The average thickness of the Martian crust is 45 km, with 32 km in the northern lowlands region, and 58 km in the southern highlands.

The boundary between the two regions is quite complex in places. One distinctive type of topography is called fretted terrain. It contains mesas, knobs, and flat-floored valleys having walls about a mile high. Around many of the mesas and knobs are lobate debris aprons that have been shown to be rock glaciers.Many large valleys formed by the lava erupted from the volcanoes of Mars cut through the dichotomy.The Martian dichotomy boundary includes the regions called Deuteronilus Mensae, Protonilus Mensae, and Nilosyrtis Mensae. All three regions have been studied extensively because they contain landforms believed to have been produced by the movement of ice or paleoshorelines questioned as formed by volcanic erosion.The northern lowlands comprise about one-third of the surface of Mars and are relatively flat, with as many impact craters as the southern hemisphere. The other two-thirds of the Martian surface are the highlands of the southern hemisphere. The difference in elevation between the hemispheres is dramatic. Three major hypotheses have been proposed for the origin of the crustal dichotomy: endogenic (by mantle processes), single impact, or multiple impact. Both impact-related hypotheses involve processes that could have occurred before the end of the primordial bombardment, implying that the crustal dichotomy has its origins early in the history of Mars.

Northern Hemisphere

The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's North Pole.Owing to the Earth's axial tilt, winter in the Northern Hemisphere lasts from the December solstice (typically December 21 UTC) to the March equinox (typically March 20 UTC), while summer lasts from the June solstice through to the September equinox (typically September 23 UTC). The dates vary each year due to the difference between the calendar year and the astronomical year.

Its surface is 60.7% water, compared with 80.9% water in the case of the Southern Hemisphere, and it contains 67.3% of Earth's land.

Spring (season)

Spring is one of the four temperate seasons, following winter and preceding summer. There are various technical definitions of spring, but local usage of the term varies according to local climate, cultures and customs. When it is spring in the Northern Hemisphere, it is autumn in the Southern Hemisphere and vice versa. At the spring (or vernal) equinox, days and nights are approximately twelve hours long, with day length increasing and night length decreasing as the season progresses.

Spring and "springtime" refer to the season, and also to ideas of rebirth, rejuvenation, renewal, resurrection and regrowth. Subtropical and tropical areas have climates better described in terms of other seasons, e.g. dry or wet, monsoonal or cyclonic. Cultures may have local names for seasons which have little equivalence to the terms originating in Europe.

Summer solstice

The summer solstice (or estival solstice), also known as midsummer, occurs when one of the Earth's poles has its maximum tilt toward the Sun. It happens twice yearly, once in each hemisphere (Northern and Southern). For that hemisphere, the summer solstice is when the Sun reaches its highest position in the sky and is the day with the longest period of daylight. At the pole, there is continuous daylight around the summer solstice. On the summer solstice, Earth's maximum axial tilt toward the Sun is 23.44°. Likewise, the Sun's declination from the celestial equator is 23.44°.

The summer solstice occurs during the hemisphere's summer. This is the June solstice in the Northern Hemisphere and the December solstice in the Southern Hemisphere. Depending on the shift of the calendar, the summer solstice occurs sometime between June 20 and June 22 in the Northern Hemisphere and between December 20 and December 23 in the Southern Hemisphere. The same dates in the opposite hemisphere are referred to as the winter solstice.

Since prehistory, the summer solstice has been seen as a significant time of year in many cultures, and has been marked by festivals and rituals. Traditionally, in many temperate regions (especially Europe), the summer solstice is seen as the middle of summer and referred to as "midsummer". Today, however, in some countries and calendars it is seen as the beginning of summer.

Westerlies

The westerlies, anti-trades, or prevailing westerlies, are prevailing winds from the west toward the east in the middle latitudes between 30 and 60 degrees latitude. They originate from the high-pressure areas in the horse latitudes and trend towards the poles and steer extratropical cyclones in this general manner. Tropical cyclones which cross the subtropical ridge axis into the westerlies recurve due to the increased westerly flow. The winds are predominantly from the southwest in the Northern Hemisphere and from the northwest in the Southern Hemisphere.

The westerlies are strongest in the winter hemisphere and times when the pressure is lower over the poles, while they are weakest in the summer hemisphere and when pressures are higher over the poles. The westerlies are particularly strong, especially in the Southern Hemisphere, in areas where land is absent, because land amplifies the flow pattern, making the current more north-south oriented, slowing the westerlies. The strongest westerly winds in the middle latitudes can come in the roaring forties, between 40 and 50 degrees latitude. The westerlies play an important role in carrying the warm, equatorial waters and winds to the western coasts of continents, especially in the southern hemisphere because of its vast oceanic expanse.

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