Circle of latitude

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Circle of latitude

A circle of latitude, on the Earth

Earth

Earth is the third planet from the Sun. Earth is the largest of the terrestrial planets in the Solar System in diameter, mass and density. It is also referred to as the World and Wiktionary:Terra.Note that by International Astronomical Union convention, the term "Terra" is used for naming extensive land masses, rather...
, is an imaginary east

East

East is a Direction in geography. It is one of the four cardinal directions or compass points, opposite of west and at right angles to north and south....
-west

West

West is most commonly a noun, adjective, or adverb indicating Direction or geography.West is one of the four cardinal directions or compass points....
circle connecting all locations (not taking into account elevation) that share a given latitude

Latitude

Latitude, usually denoted symbolically by the Greek letter phi gives the location of a place on Earth north or south of the equator. Lines of Latitude are the horizontal lines shown running east-to-west on maps ....
. A location's position along a circle of latitude is given by its longitude

Longitude

Longitude , symbolized by the Greek character lambda , is the geographic coordinate most commonly used in cartography and global navigation for east-west measurement....
.

Circles of latitude are often called parallels because they are parallel to each other. On some map projections, including the Mercator projection

Mercator projection

The Mercator projection is a Map projection#Triangular presented by the Flemish people geographer and cartographer Gerardus Mercator, in 1569....
, they are drawn at equidistant intervals.

Circles of latitude become smaller the farther they are from the equator and the closer they are to the poles

Geographical pole

A geographical pole , is either of two points on the surface of a spinning planet or other spinning body, at 90 degrees from its equator, at one of the two points where the Axis of rotation around which the body spins meets the surface of the body....
.

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A circle of latitude, on the Earth

Earth

East

East is a Direction in geography. It is one of the four cardinal directions or compass points, opposite of west and at right angles to north and south....
-west

West

Latitude

Longitude

Mercator projection

Geographical pole

Meridian (geography)

A meridian is an imaginary arc on the Earth's surface from the North Pole to the South Pole that connects all locations running along it with a given longitude....
s at the points of intersection, and is hence a special case of a loxodrome.

Contrary to what might be assumed from their straight-line representation on some map projections, a circle of latitude is not, with the sole exception of the Equator, the shortest distance between two points lying on the Earth. In other words, circles of latitude (except for the Equator) are not great circle

Great circle

A great circle of a sphere is a circle that runs along the surface of that sphere so as to cut it into two equal halves. The great circle therefore has both the same circumference and the same center as the sphere....
s, and are not really "lines" in the geometric sense (see also great-circle distance

Great-circle distance

The great-circle distance is the shortest distance between any two Point s on the surface of a sphere measured along a path on the surface of the sphere ....
). It is for this reason that an airplane traveling between a European and North American city that share the same latitude will fly farther north, over Greenland

Greenland

Greenland is a member country of the Kingdom of Denmark located between the Arctic Ocean and Atlantic Oceans, east of the Canadian Arctic Archipelago....
for example.

Arcs of circles of latitude are sometimes used as boundaries between countries or regions where distinctive natural borders are lacking (such as in deserts), or when an artificial border is drawn as a "line on a map", as happened in Korea

38th parallel north

The 38th parallel north is a circle of latitude that is 38 degree true north of the Earth equator. The 38th parallel north has been especially important in the recent history of Korea....
.

Major circles of latitude

The five major circles of latitude are, from north to south:

The Arctic Circle
Arctic Circle

The Arctic Circle is one of the five major circle of latitude that mark maps of the Earth. It is the parallel of latitude that runs 66degree 33'39? north of the Equator....
(66° 33' 38? N)
The Tropic of Cancer
Tropic of Cancer

The Tropic of Cancer, or Northern tropic, is one of five major degree measures or major circle of latitude that mark maps of the Earth. It is the northernmost latitude at which the Sun can appear directly overhead at noon....
(23° 26' 22? N)
The Equator
Equator

The equator is the intersection of the Earth's surface with the Plane perpendicular to the Earth's rotation and containing the Earth's center of mass....
(0° latitude)
The Tropic of Capricorn
Tropic of Capricorn

The Tropic of Capricorn, or Southern tropic, is one of the five major circle of latitude that mark maps of the Earth. It lies 23degree 26' 22? south of the Equator, and marks the most southerly latitude at which the sun can appear directly overhead at noon....
(23° 26' 22? S)
The Antarctic Circle
Antarctic Circle

The Antarctic Circle is one of the five major circle of latitude that mark maps of the Earth. As of 2000, it lies at latitude 66degree 33' 39? south of the equator....
(66° 33' 38? S)

These circles of latitude (excluding the equator) mark the divisions between the five principal geographical zone

Geographical zone

Each of the five main latitude regions of the earth's surface is said to be a geographical zone, divided by the major circles of latitude. The differences between them relate to climate, and the behaviour of the sun....
s.

Equator

The equator is the circle that is equidistant from both the North Pole

North Pole

The North Pole, also known as the Geographic North Pole or Terrestrial North Pole is, subject to the caveats explained below, defined as the point in the northern hemisphere where the Earth's axis of rotation meets the Earth's surface....
and South Pole

South Pole

The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's rotation intersects the surface....
. It divides the Earth into the Northern Hemisphere

Northern Hemisphere

Southern Hemisphere


Equator Equator The equator is the intersection of the Earth's surface with the Plane perpendicular to the Earth's rotation and containing the Earth's center of mass....

Arctic and Antarctic Circles

The Arctic Circle marks the southernmost latitude (in the Northern Hemisphere

Northern Hemisphere

The Northern Hemisphere is the half of a planet that is north of the equator?the word sphere literally means 'half sphere'. It is also that half of the celestial sphere north of the celestial equator....
) at which the sun can remain continuously above or below the horizon for 24 hours. Similarly, the Antarctic Circle marks the northernmost latitude (in the Southern Hemisphere

Southern Hemisphere

The Southern Hemisphere is the half of a planet that is south of the equator?the word sphere literally means 'half ball'. It is also that half of the celestial sphere south of the celestial equator....
) at which the sun can remain continuously above or below the horizon for 24 hours.

The latitude of these circles plus the Earth's axial tilt

Axial tilt

In astronomy, axial tilt is the inclination angle of a planet axis of rotation in relation to its Orbital plane . It is also called axial inclination or obliquity....
is equal to 90°.


Arctic Circle Arctic Circle The Arctic Circle is one of the five major circle of latitude that mark maps of the Earth. It is the parallel of latitude that runs 66degree 33'39? north of the Equator....


Antarctic Circle Antarctic Circle The Antarctic Circle is one of the five major circle of latitude that mark maps of the Earth. As of 2000, it lies at latitude 66degree 33' 39? south of the equator....

Tropics of Cancer and Capricorn

The Tropic of Cancer and Tropic of Capricorn respectively mark the northernmost and southernmost latitudes at which the sun may be seen directly overhead (at the June solstice and December solstice respectively).

The latitude of the tropic circles is equal to the Earth's axial tilt

Axial tilt

In astronomy, axial tilt is the inclination angle of a planet axis of rotation in relation to its Orbital plane . It is also called axial inclination or obliquity....
.


Tropic of Cancer Tropic of Cancer The Tropic of Cancer, or Northern tropic, is one of five major degree measures or major circle of latitude that mark maps of the Earth. It is the northernmost latitude at which the Sun can appear directly overhead at noon....


Tropic of Capricorn Tropic of Capricorn The Tropic of Capricorn, or Southern tropic, is one of the five major circle of latitude that mark maps of the Earth. It lies 23degree 26' 22? south of the Equator, and marks the most southerly latitude at which the sun can appear directly overhead at noon....

Movement of the Tropics and the Arctic and Antarctic circles

See also: Axial tilt
Axial tilt

In astronomy, axial tilt is the inclination angle of a planet axis of rotation in relation to its Orbital plane . It is also called axial inclination or obliquity....
.

By definition, the positions of the Tropic of Cancer

Tropic of Cancer

The Tropic of Cancer, or Northern tropic, is one of five major degree measures or major circle of latitude that mark maps of the Earth. It is the northernmost latitude at which the Sun can appear directly overhead at noon....
, Tropic of Capricorn

Tropic of Capricorn

The Tropic of Capricorn, or Southern tropic, is one of the five major circle of latitude that mark maps of the Earth. It lies 23degree 26' 22? south of the Equator, and marks the most southerly latitude at which the sun can appear directly overhead at noon....
, Arctic Circle

Arctic Circle

The Arctic Circle is one of the five major circle of latitude that mark maps of the Earth. It is the parallel of latitude that runs 66degree 33'39? north of the Equator....
and Antarctic Circle

Antarctic Circle

The Antarctic Circle is one of the five major circle of latitude that mark maps of the Earth. As of 2000, it lies at latitude 66degree 33' 39? south of the equator....
all depend on the tilt of the Earth's axis

Axial tilt

In astronomy, axial tilt is the inclination angle of a planet axis of rotation in relation to its Orbital plane . It is also called axial inclination or obliquity....
relative to the plane of its orbit around the sun, known technically as the "obliquity of the ecliptic". As of 2000, the mean value of the tilt was about 23°26'21?. However, this angle is not constant, but has a complex motion determined by the superimposition of many different cycles with short to very long periods. As the axial tilt varies, so do the positions of the Tropics and the Arctic and Antarctic circles.

The main long-term cycle causes the axial tilt to fluctuate between about 22.5° and 24.5° with a 41,000 year periodicity. As a consequence of this cycle the average value of the tilt is currently decreasing by about 0.47? per year. This causes the Tropics of Cancer and Capricorn to drift towards the equator by about 15 metres per year, and the Arctic and Antarctic Circles to drift towards the Poles by the same amount. As a result of the movement of the Tropics of Cancer and Capricorn, the area of the Tropics

Tropics

The Tropics, seated in the equatorial regions of the world, are limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately 23?26' N latitude, and the Tropic of Capricorn in the southern hemisphere at 23?26' S latitude....
decreases worldwide by about 1100 square kilometres per year on average.

The Earth's axial tilt is subject to additional shorter-term variations due to nutation

Nutation

Nutation is a slight irregular motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope or a planet.Nutation is also the name of one of the Euler_angles#Euler_rotations, the Euler rotation that measures the change in angle due to the "nodding" mentioned above....
, of which the main term, with a period of 18.7 years, has an amplitude

Amplitude

Amplitude is the magnitude of change in the oscillating variable, with each oscillation, within an oscillating system. For instance, sound waves are oscillations in atmospheric pressure and their amplitudes are proportional to the change in pressure during one oscillation....
of 9"21 (corresponding to almost 300 metres north and south). There are then still many smaller terms, resulting in varying daily shifts of some metres in any direction.

Finally, the Earth's rotational axis is not exactly fixed with respect to the Earth, but undergoes very small fluctuations, called polar motion

Polar motion

Polar motion is the movement of Earth's Earth's rotation axis across its surface. This is measured with respect to a reference frame in which the solid Earth is fixed ....
, which have a small theoretical effect on the positions of the abovementioned parallels.

Short-term fluctuations over a matter of days do not directly affect the location of the extreme latitudes at which the sun may appear directly overhead, or at which 24-hour day or night is possible, except when they actually occur at the time of the solstices. Rather, they cause a theoretical shifting of the parallels, that would occur if the given axis tilt were maintained throughout the year.

Other notable parallels

A number of sub-national and international border

Border

Borders define geography boundaries of political geography or legal jurisdictions, such as governments, states or Subnational entity. They may foster the setting up of buffer zones....
s are defined by parallels.

Parallel	Description
70°N 70th parallel north The 70th parallel north is a circle of latitude that is 70 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 70? north passes through:...	On Victoria Island Victoria Island Victoria Island is an island in the Canadian Arctic Archipelago and straddles the boundary between Nunavut and the Northwest Territories of Canada.... , , two sections of the border between Northwest Territories Northwest Territories The Northwest Territories are a provinces and territories of Canada of Canada.Located in northern Canada, it borders Canada's two other territories, Yukon to the west and Nunavut to the east, and three provinces: British Columbia to the southwest, Alberta and Saskatchewan to the south.... and Nunavut Nunavut Nunavut is the largest and newest Provinces and territories of Canada of Canada; it was separated officially from the Northwest Territories on April 1, 1999 via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993.... .
60°N 60th parallel north The 60th parallel north is a circle of latitude that is 60 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 60? north passes through:...	In , the southern border of Yukon Yukon Yukon is the westernmost and smallest of Canada three Territories of Canada. It was named after the Yukon River, Yukon meaning "Great River" in Gwich?in language.... with the northern border of British Columbia British Columbia British Columbia is the westernmost of Canada's Provinces and territories of Canada and is famed for its natural beauty, as reflected in its Latin motto, Splendor sine occasu .... ; the southern border of Northwest Territories Northwest Territories The Northwest Territories are a provinces and territories of Canada of Canada.Located in northern Canada, it borders Canada's two other territories, Yukon to the west and Nunavut to the east, and three provinces: British Columbia to the southwest, Alberta and Saskatchewan to the south.... with the northern borders of British Columbia British Columbia British Columbia is the westernmost of Canada's Provinces and territories of Canada and is famed for its natural beauty, as reflected in its Latin motto, Splendor sine occasu .... , Alberta Alberta Alberta is one of Canada Canadian Prairies Provinces and territories of Canada. It became a province on September 1, 1905.Alberta is located in western Canada, bounded by the provinces of British Columbia to the west and Saskatchewan to the east, the Northwest Territories to the north, and the U.S.... and Saskatchewan Saskatchewan Saskatchewan is a prairie provinces in Canada, which has an area of 588,276.09 square kilometres and a population of 1,015,895 , mostly living in the southern half of the province.... ; and the southern border of mainland Nunavut Nunavut Nunavut is the largest and newest Provinces and territories of Canada of Canada; it was separated officially from the Northwest Territories on April 1, 1999 via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993.... with the northern border of Manitoba Manitoba Manitoba is a prairie provinces in Canada, which has an area of 647,797 square kilometres and a population of 1,207,959 , with more than half located within the Winnipeg Capital Region .... ).
54°40'N Parallel 54°40' north The parallel 54?40' north forms the southernmost boundary between the U.S. State of Alaska and the Canada Province of British Columbia....	The border between 19th century Russian and British land claims in western North America which played a role in the Oregon boundary dispute Oregon boundary dispute The Oregon boundary dispute, or the Oregon question, arose as a result of competing United Kingdom of Great Britain and Ireland and United States claims to the Pacific Northwest of North America in the first half of the 19th century.... between Britain and the United States, giving rise to the slogan "Fifty-four forty or fight."
52°N 52nd parallel north The 52nd parallel north is a circle of latitude that is 52 degree true north of the Earth equator.In Canada, part of the border between Quebec and Newfoundland and Labrador is defined by the parallel....	In , part of the border between Newfoundland and Labrador Newfoundland and Labrador Newfoundland and Labrador is a Provinces and territories of Canada of Canada, on the country's Atlantic Ocean coast in northeastern North America.... and Quebec Quebec Quebec , in French language, *Qu?bec* , is a Provinces and territories of Canada in the Central Canada and Eastern Canada regions of Canada.... .
49°N 49th parallel north The 49th parallel north is a circle of latitude that is 49 degree true north of the Earth equator.The parallel forms part of the United States-Canadian Border from British Columbia to Manitoba on the Canada side and from Washington to Minnesota on the United States side, or from the Strait of Georgia to the Lake of the Woods....	Much of the border between and the , from Washington Washington Washington is a U.S. state in the Pacific Northwest region of the United States. Washington was carved out of the western part of Washington Territory which had been ceded by Britain in 1846 by the Oregon Treaty as settlement of the Oregon Boundary Dispute.... to western Minnesota Minnesota Minnesota is a U.S. state in the Midwestern United States of the United States. The twelfth largest state by area in the U.S., it is the twenty-first most populous, with just over five million residents.... .
48°N 48th parallel north The 48th parallel north is a circle of latitude that is 48 degree true north of the Earth equator....	In , part of the border between Quebec Quebec Quebec , in French language, *Qu?bec* , is a Provinces and territories of Canada in the Central Canada and Eastern Canada regions of Canada.... and New Brunswick New Brunswick New Brunswick is one of Canada's three Maritime provinces and is the only Constitution of Canada bilingual province in the federation. The provincial capital is Fredericton.... .
45°N	The theoretical halfway point between the Equator and the North Pole. Part of the border between (Quebec Quebec Quebec , in French language, *Qu?bec* , is a Provinces and territories of Canada in the Central Canada and Eastern Canada regions of Canada.... ) and the (New York New York The State of New York is a U.S. state in the Mid-Atlantic States and Northeastern United States regions of the United States and is the nation's List of U.S.... and Vermont Vermont Vermont is a U.S. state in the New England region of the Northeastern United States United States. The state ranks 43rd by land area, , and 45th by total area.... ). Also, in the , most of the border between Montana Montana Montana is a U.S. state in the Western United States. The western third of the state contains numerous mountain ranges; other 'island' ranges are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains.... and Wyoming Wyoming The State of Wyoming is a sparsely populated U.S. state in the Northwestern United States of the United States. The majority of the state is dominated by the mountain ranges and rangelands of the Rocky Mountains, while the easternmost section of the state is a high altitude prairie region known as the High Plains .... .
43°N 43rd parallel north The 43rd parallel north is a circle of latitude that is 43 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 43? north passes through:...	In the , much of the border between South Dakota South Dakota South Dakota is a U.S. state located in the Midwestern United States of the United States of America. It is named after the Lakota people and Sioux Sioux Native Americans in the United States tribes.... and Nebraska Nebraska Nebraska is a U.S. state located on the Great Plains of the Midwestern United States and Western United States.Nebraska probably gets its name from the archaic Chiwere language words ?? Br?sge or the Omaha-Ponca language N? Bth?ska meaning "flat water," after the Platte River that flows through the state.... .
42°N 42nd parallel north The 42nd parallel north is a circle of latitude that is 42 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 42? north passes through:...	In the , the southern borders of Oregon Oregon Oregon is a U.S. state in the Pacific Northwest region of the United States. The area was inhabited by many indigenous tribes before the arrival of traders, explorers and settlers.... and Idaho Idaho The State of Idaho is a U.S. state in the Pacific Northwest region of the United States of America. The state's largest city and Capital is Boise, Idaho.... where they meet the northern borders of California California California is a U.S. state on the West Coast of the United States of the United States, along the Pacific Ocean. It is bordered by Oregon to the north, Nevada to the east, Arizona to the southeast, and to the south the Mexico state of Baja California.... , Nevada Nevada Nevada is a U.S. state located in the Western United States of the United States of America. The capital is Carson City and the largest city is Las Vegas, Nevada.... and Utah Utah The State of Utah is a western United States U.S. state of the United States. It was the List of U.S. states by date of statehood admitted to the United States on January 4, 1896.... . The parallel also defines much of the border between Pennsylvania Pennsylvania The Commonwealth of Pennsylvania , often colloquially referred to as PA by natives and Northeasterners, is a U.S. state located in the Northeastern United States and Mid-Atlantic States regions of the United States.... and New York New York The State of New York is a U.S. state in the Mid-Atlantic States and Northeastern United States regions of the United States and is the nation's List of U.S.... .
41°N 41st parallel north The 41st parallel north is a circle of latitude that is 41 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 41? north passes through:...	In the , part of the border between Wyoming Wyoming The State of Wyoming is a sparsely populated U.S. state in the Northwestern United States of the United States. The majority of the state is dominated by the mountain ranges and rangelands of the Rocky Mountains, while the easternmost section of the state is a high altitude prairie region known as the High Plains .... and Utah Utah The State of Utah is a western United States U.S. state of the United States. It was the List of U.S. states by date of statehood admitted to the United States on January 4, 1896.... , the border between Wyoming Wyoming The State of Wyoming is a sparsely populated U.S. state in the Northwestern United States of the United States. The majority of the state is dominated by the mountain ranges and rangelands of the Rocky Mountains, while the easternmost section of the state is a high altitude prairie region known as the High Plains .... and Colorado Colorado The State of Colorado is a U.S. state located in the Mountain States of the United States of America. Colorado may also be considered to be a part of the Western United States and Southwestern United States regions of the United States.... , and part of the border between Nebraska Nebraska Nebraska is a U.S. state located on the Great Plains of the Midwestern United States and Western United States.Nebraska probably gets its name from the archaic Chiwere language words ?? Br?sge or the Omaha-Ponca language N? Bth?ska meaning "flat water," after the Platte River that flows through the state.... and Colorado Colorado The State of Colorado is a U.S. state located in the Mountain States of the United States of America. Colorado may also be considered to be a part of the Western United States and Southwestern United States regions of the United States.... .
40°N 40th parallel north The 40th parallel north is a circle of latitude that is 40 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 40? north passes through:...	In the , the border between Nebraska Nebraska Nebraska is a U.S. state located on the Great Plains of the Midwestern United States and Western United States.Nebraska probably gets its name from the archaic Chiwere language words ?? Br?sge or the Omaha-Ponca language N? Bth?ska meaning "flat water," after the Platte River that flows through the state.... and Kansas Kansas The State of Kansas is a Midwestern U.S. state in the Central United States of the United States of America, an area often referred to as the United States "Heartland".... . The parallel was originally chosen for the Mason-Dixon Line Mason-Dixon line The Mason?Dixon Line was surveyed between 1763 and 1767 by Charles Mason and Jeremiah Dixon in the resolution of a border dispute between British colonies in Colonial America.... , but the line was moved several miles south to avoid bisecting the city of Philadelphia.
38°N 38th parallel north The 38th parallel north is a circle of latitude that is 38 degree true north of the Earth equator. The 38th parallel north has been especially important in the recent history of Korea....	The boundary between the Soviet Soviet Union The Union of Soviet Socialist Republics was a Constitution of the Soviet Union socialist state that existed in Eurasia from 1922 to 1991.The name is a translation of the , romanization of Russian Soyuz Sovetskikh Sotsialisticheskikh Respublik, abbreviated ????, SSSR.... and American occupation zones in Korea Korea Korea is a geographic area composed of two sovereign countries, a civilization, and a former state situated on the Korean Peninsula in East Asia.... from 1945 until Korean War Korean War The Korean War refers to a period of military conflict between North Korea and South Korea regimes, with major hostilities lasting from June 25, 1950 until the armistice signed on July 27, 1953.... (1950-1953).
37°N 37th parallel north The 37th parallel north is a circle of latitude that is 37 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 37? north passes through:...	In the , the southern border of Utah Utah The State of Utah is a western United States U.S. state of the United States. It was the List of U.S. states by date of statehood admitted to the United States on January 4, 1896.... with the northern border of Arizona Arizona The State of Arizona is a U.S. state located in the Southwestern United States of the United States. The capital and largest city is Phoenix, Arizona.... . The southern border of Colorado Colorado The State of Colorado is a U.S. state located in the Mountain States of the United States of America. Colorado may also be considered to be a part of the Western United States and Southwestern United States regions of the United States.... with the northern borders of New Mexico New Mexico New Mexico is a U. S. State located in the Southwestern United States of the United States. Inhabited by Native Americans in the United States populations for many centuries, it has also has been part of the Spanish Empire viceroyalty of New Spain, part of Mexico, and a U.S.... and Oklahoma Oklahoma Oklahoma is a U.S. state and a sovereignty located in the South Central United States and Southern United States of the United States of America .... . The southern border of Kansas Kansas The State of Kansas is a Midwestern U.S. state in the Central United States of the United States of America, an area often referred to as the United States "Heartland".... with the northern border of Oklahoma Oklahoma Oklahoma is a U.S. state and a sovereignty located in the South Central United States and Southern United States of the United States of America .... .
36°30'N	The historic Missouri Compromise Missouri Compromise The Missouri Compromise was an agreement passed in 1820 between the slave state and free state factions in the United States Congress, involving primarily the regulation of slavery in the Historic regions of the United States.... line. In the , defines part of the border between Oklahoma Oklahoma Oklahoma is a U.S. state and a sovereignty located in the South Central United States and Southern United States of the United States of America .... and Texas Texas Texas is a U.S. state located in the South Central United States, nicknamed the Lone Star State. Texas is the second largest U.S. state in both area and population, spanning , and with a growing population of 24.3 million residents.... , most of the border between Missouri Missouri Missouri is a U.S. state in the Midwestern United States of the United States bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska.... and Arkansas Arkansas Arkansas is a U.S. state located in the Southern United States of the United States. Arkansas shares a border with six states, with its eastern border largely defined by the Mississippi River.... . Geographically it is a Westward extension of the border between Virginia Virginia The Commonwealth of Virginia is an United States U.S. state on the East Coast of the United States of the Southern United States. The state is known as the "Old Dominion" and sometimes as "Mother of Presidents", because it is the birthplace of Lists of United States Presidents by place of birth#By state.... and North Carolina North Carolina North Carolina is a U.S. state located on the Atlantic Seaboard in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north.... and part of the border between Kentucky Kentucky The Commonwealth of Kentucky is a U.S. state located in the East Central United States of America. Kentucky is normally included in the group of Southern United States , but it is uncommonly included, geographically and culturally, in the Midwestern United States.... and Tennessee Tennessee Tennessee is a U.S. state located in the Southern United States United States. In 1796, it became the sixteenth state to join the United States.... .
36°N 36th parallel north The 36th parallel north is a circle of latitude that is 36 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 36? north passes through:...	In the , a short section of the border between the Missouri Bootheel and Arkansas Arkansas Arkansas is a U.S. state located in the Southern United States of the United States. Arkansas shares a border with six states, with its eastern border largely defined by the Mississippi River.... .
35°N 35th parallel north The 35th parallel north is a circle of latitude that is 35 degree true north of the Earth equator.In the United States, the parallel defines the southern border of Tennessee, and the border between North Carolina and Georgia ....	In the , the southern border of Tennessee Tennessee Tennessee is a U.S. state located in the Southern United States United States. In 1796, it became the sixteenth state to join the United States.... , which meets Mississippi Mississippi Mississippi is a U.S. state located in the Deep South of the United States. Jackson, Mississippi is the state capital and largest city. The state's name comes from the Mississippi River, which flows along its western boundary, and takes its name from the Anishinaabe language word misi-ziibi .... , Alabama Alabama Alabama is a state located in the Southern United States of the United States of America. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west.... and Georgia Georgia (U.S. state) Georgia is a U.S. state in the United States and was one of the original Thirteen Colonies that revolted against United Kingdom rule in the American Revolution.... . Also, part of the border between North Carolina North Carolina North Carolina is a U.S. state located on the Atlantic Seaboard in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north.... and Georgia Georgia (U.S. state) Georgia is a U.S. state in the United States and was one of the original Thirteen Colonies that revolted against United Kingdom rule in the American Revolution.... .
33°N 33rd parallel north The 33rd parallel north is a circle of latitude that is 33 degree true north of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 33? north passes through:...	In the , the southern border of Arkansas Arkansas Arkansas is a U.S. state located in the Southern United States of the United States. Arkansas shares a border with six states, with its eastern border largely defined by the Mississippi River.... , which meets the northern border of Louisiana Louisiana The State of Louisiana is a U.S. state located in the U.S. Southern States of the United States of America. Its capital is Baton Rouge and largest city is New Orleans.... . Historically, it defined the southern border of the Louisiana Territory Louisiana Territory Louisiana Territory was a historic organized territory of the United States consisting of the portion of the Louisiana Purchase that was not partitioned off into Territory of Orleans, which later became the state of Louisiana.... .
32°N 32nd parallel north The 32nd parallel north is a circle of latitude that is 32 degree true north of the Earth equator.In the United States, the parallel defines part of the border between New Mexico and Texas....	In the , part of the border between New Mexico New Mexico New Mexico is a U. S. State located in the Southwestern United States of the United States. Inhabited by Native Americans in the United States populations for many centuries, it has also has been part of the Spanish Empire viceroyalty of New Spain, part of Mexico, and a U.S.... and Texas Texas Texas is a U.S. state located in the South Central United States, nicknamed the Lone Star State. Texas is the second largest U.S. state in both area and population, spanning , and with a growing population of 24.3 million residents.... .
31°N 31st parallel north The 31st parallel north is a circle of latitude that is 31 degree true north of the Earth equator.Part of the border between Iran and Iraq is defined by the parallel....	Part of the border between and . In the , part of the border between Mississippi Mississippi Mississippi is a U.S. state located in the Deep South of the United States. Jackson, Mississippi is the state capital and largest city. The state's name comes from the Mississippi River, which flows along its western boundary, and takes its name from the Anishinaabe language word misi-ziibi .... and Louisiana Louisiana The State of Louisiana is a U.S. state located in the U.S. Southern States of the United States of America. Its capital is Baton Rouge and largest city is New Orleans.... , and part of the border between Alabama Alabama Alabama is a state located in the Southern United States of the United States of America. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west.... and Florida Florida Florida is a U.S. state located in the Southeastern United States of the United States, bordering Alabama to the northwest and Georgia to the northeast.... .
28°N 28th parallel north The 28th parallel north is a circle of latitude that is 28 degree true north of the Earth equator.In Mexico the parallel defines the border between the states of Baja California and Baja California Sur....	In , the border between Baja California Baja California Baja California is the northernmost States of Mexico of Mexico. Before becoming a state in 1953, the area was known as the North Territory of Baja California.... and Baja California Sur Baja California Sur Baja California Sur The state is known for its natural riches and tourism. The Vizca?no Desert and small coastal lakes San Ignacio and Ojo de Liebre in the north are protected by the federal government.... .
26°N 26th parallel north The 26th parallel north is a circle of latitude that is 26 degree true north of the Earth equator.A section of the border between Western Sahara and Mauritania is defined by the parallel....	Part of the border between Western Sahara Western Sahara Western Sahara is a territory of North Africa, bordered by Morocco to the north, Algeria in the northeast, Mauritania to the east and south, and the Atlantic Ocean on the west.... (claimed by ) and .
25°N 25th parallel north The 25th parallel north is a circle of latitude that is 25 degree true north of the Earth equator, just north of the Tropic of Cancer.The northernmost section of the border between Mauritania and Mali is defined by the parallel....	Part of the border between and .
24°N 24th parallel north The 24th parallel north is a circle of latitude that is 24 degree true north of the Earth equator.The parallel defines a short section of the border between India and Myanmar ....	A short section of the border between and (Burma).
22°N 22nd parallel north The 22nd parallel north is a circle of latitude that is 22 degree true north of the Earth equator.The majority of the border between Egypt and Sudan follows the parallel....	Much of the border between and , partly disputed (see also Hala'ib Triangle Hala'ib Triangle The Hala'ib Triangle or Halayeb Triangle is an area of land measuring 20,580 km? located on the Red Sea African coast, between the political borders of Egypt and the administrative boundary .... ).
20°N 20th parallel north The 20th parallel north is a circle of latitude that is 20 degree true north of the Earth equator.The parallel defines part of the border between Libya and Sudan, and within Sudan it defines the border between the Northern, Sudan and North Darfur states....	A short section of the border between and , and within Sudan, the northern border of the Darfur Darfur Darfur is a region in Sudan. An independent sultanate for several hundred years, it was incorporated into Sudan by History of the Anglo-Egyptian co-dominium.... region.
17°N 17th parallel north The 17th parallel north is a circle of latitude that is 17 degree true north of the Earth equator.The parallel is particularly significant in the history of Vietnam ....	The division between Republic of Vietnam (South Vietnam) and Democratic Republic of Vietnam (North Vietnam) during the Vietnam War Vietnam War The Vietnam War, also known as the Second Indochina Wars, the Vietnam Conflict, or often in Vietnam the American War occurred in Vietnam, Laos and Cambodia from 1959 to April 30, 1975.... .
10°N 10th parallel north The 10th parallel north is a circle of latitude that is 10 degree true north of the Earth equator.A section of the border between Guinea and Sierra Leone is defined by the parallel....	Part of the border between and .
8°N 8th parallel north The 8th parallel north is a circle of latitude that is 8 degree true north of the Earth equator.The parallel defines part of the border between Somalia and Ethiopia....	Part of the border between and .
1°N 1st parallel north The 1st parallel north is a circle of latitude that is 1 degree true north of the Earth equator.The parallel defines part of the border between Equatorial Guinea and Gabon....	Part of the border between and .
1°S 1st parallel south The 1st parallel south is a circle of latitude that is 1 degree south of the Earth equator.The parallel defines most of the border between Uganda and Tanzania, and a very short section of the border between Kenya and Tanzania....	Most of the border between and , and a very short section of the border between and in Lake Victoria Lake Victoria Lake Victoria or Victoria Nyanza is one of the Great Lakes of Africa.Lake Victoria is 68,800 square kilometres in size, making it the continent's largest lake, the largest tropical lake in the world, and the second widest fresh water lake in the world in terms of surface area .... .
7°S 7th parallel south The 7th parallel south is a circle of latitude that is 7 degree south of the Earth equator.Part of the border between the Democratic Republic of the Congo and Angola is defined by the parallel....	A short section of the border between and .
8°S 8th parallel south The 8th parallel south is a circle of latitude that is 8 degree south of the Earth equator.Two sections of the border between the Democratic Republic of the Congo and Angola are defined by the parallel....	Two short sections of the border between and .
10°S 10th parallel south The 10th parallel south is a circle of latitude that is 10 degree south of the Earth equator.Part of the border between Brazil and Peru is defined by the parallel....	A short section of the border between and .
13°S 13th parallel south The 13th parallel south is a circle of latitude that is 13 degree south of the Earth equator.Part of the border between Angola and Zambia is defined by the parallel....	Part of the border between and .
13°S 13th parallel south The 13th parallel south is a circle of latitude that is 13 degree south of the Earth equator.Part of the border between Angola and Zambia is defined by the parallel....	Part of the border between and .
16°S 16th parallel south The 16th parallel south is a circle of latitude that is 16 degree south of the Earth equator.A section of the border between Mozambique and Zimbabwe is defined by the parallel....	Part of the border between and .
22°S 22nd parallel south The 22nd parallel south is a circle of latitude that is 22 degree south of the Earth equator.A section of the border between Namibia and Botswana, and two sections of the border between Bolivia and Argentina are defined by the parallel....	A short section of the border between and , and parts of the border between and .
26°S 26th parallel south The 26th parallel south is a circle of latitude that is 26 degree south of the Earth equator. It crosses through Africa, Australia and South America....	In , the border between South Australia South Australia South Australia is a States and territories of Australia of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.... and the Northern Territory Northern Territory The Northern Territory is a federal states and territories of Australia of Australia, occupying much of the centre of the mainland continent, as well as the central northern regions.... , and part of the border between South Australia South Australia South Australia is a States and territories of Australia of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.... and Queensland Queensland Queensland is a States and territories of Australia of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory to the west, South Australia to the south-west and New South Wales to the south.... .
29°S 29th parallel south The 29th parallel south is a circle of latitude that is 29 degree south of the Earth equator.In Australia, much of the border between Queensland and New South Wales is defined by the parallel....	In , much of the border between Queensland Queensland Queensland is a States and territories of Australia of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory to the west, South Australia to the south-west and New South Wales to the south.... and New South Wales New South Wales New South Wales is Australia's oldest and most populous States and territories of Australia, located in the south-east of the country, north of Victoria and south of Queensland.... .
35°S 35th parallel south The 35th parallel south is a circle of latitude that is 35 degree south of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 35? south passes through:...	In , part of the border between Córdoba Province Córdoba Province (Argentina) C?rdoba is a Provinces of Argentina of Argentina, located in the center of the country. Its capital, C?rdoba, Argentina, is the second largest city in the country.... and La Pampa Province La Pampa Province La Pampa is a Provinces of Argentina of Argentina, located in the Pampas in the center of the country. Neighboring provinces are from the north clockwise San Luis Province, C?rdoba Province, Argentina, Buenos Aires Province, R?o Negro Province, Neuqu?n Province and Mendoza Province.... .
36°S 36th parallel south The 36th parallel south is a circle of latitude that is 36 degree south of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 36? south passes through:...	In , part of the border between Mendoza Province Mendoza Province Mendoza is one of the Provinces of Argentina of Argentina, located in the western central part of the country in the Cuyo, Argentina region. Neighboring provinces are from the north clockwise San Juan Province, Argentina, San Luis Province, La Pampa,and Neuqu?n Province.... and La Pampa Province La Pampa Province La Pampa is a Provinces of Argentina of Argentina, located in the Pampas in the center of the country. Neighboring provinces are from the north clockwise San Luis Province, C?rdoba Province, Argentina, Buenos Aires Province, R?o Negro Province, Neuqu?n Province and Mendoza Province.... .
42°S 42nd parallel south The 42nd parallel south is a circle of latitude that is 42 degree south of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 42? south passes through:...	In , the border between Río Negro Province Río Negro Province R?o Negro is a Provinces of Argentina of Argentina, located at the northern edge of Patagonia. Neighboring provinces are from the south clockwise Chubut Province, Neuqu?n Province, Mendoza Province, La Pampa and Buenos Aires Province.... and Chubut Province Chubut Province Chubut a province in the southern part of Argentina situated between the 42nd Circle of latitude South and 46th Parallel South , the Andes range separating Argentina from Chile, and the Atlantic ocean.... .
45°S 45th parallel south The 45th parallel south is a circle of latitude that is 45 degree south of the Earth equator. The parallel is the line that marks the theoretical halfway point between the equator and the South Pole....	The theoretical halfway point between the Equator and the South Pole.
46°S 46th parallel south The 46th parallel south is a circle of latitude that is 46 degree south of the Earth equator.Starting at the Prime Meridian and heading eastwards, the parallel 46? south passes through:...	In , the border between Chubut Province Chubut Province Chubut a province in the southern part of Argentina situated between the 42nd Circle of latitude South and 46th Parallel South , the Andes range separating Argentina from Chile, and the Atlantic ocean.... and Santa Cruz Province Santa Cruz Province (Argentina) Santa Cruz is a Provinces of Argentina of Argentina, located in the southern part of the country, in Patagonia. It borders Chubut Province province to the north, and Chile to the west and south.... .
52°S 52nd parallel south The 52nd parallel south is a circle of latitude that is 52 degree south of the Earth equator.The parallel defines part of the border between Argentina and Chile....	Part of the border between and .
60°S 60th parallel south The 60th parallel south is a circle of latitude that is 60 degree south of the Earth equator.The parallel marks the northern limit of the Southern Ocean....	The northern boundary of Antarctica Antarctica Antarctica is Earth's southernmost continent, overlying the South Pole. It is situated in the Antarctica of the southern hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean.... for the purposes of the Antarctic Treaty System Antarctic Treaty System The Antarctic Treaty and related agreements, collectively called the Antarctic Treaty System or ATS, regulate international relations with respect to Antarctica, Earth's only continent without a native human population.... (see ). The northern boundary of the Southern Ocean Southern Ocean The Southern Ocean, also known as the Great Southern Ocean, the Antarctic Ocean and the South Polar Ocean, comprises the southernmost waters of the World Ocean south of 60th parallel south latitude.... .

Altitude

Altitude has an effect on a location's position relative to the plane

Plane (mathematics)

In mathematics, a plane is a curvature surface. Planes can arise as subspaces of some higher dimensional space, as with the walls of a room, or they may enjoy an independent existence in their own right, as in the setting of Euclidean geometry....
formed by a circle of latitude. Since latitude is determined by the normal

Surface normal

A surface normal, or simply normal, to a Flatness is a vector which is perpendicular to that surface. A normal to a non-flat surface at a Point P on the surface is a vector perpendicular to the Tangent space to that surface at P....
to the Earth's surface, locations sharing the same latitude—but having different elevations (e.g., lying along this normal)—no longer lie within this plane. Rather, all points sharing the same latitude and of varying elevation occupy a cone

Conical surface

In geometry, a conical surface is the unbounded surface formed by the union of all the straight line that pass through a fixed point — the apex or vertex — and any point of some fixed space curve — the directrix — that does not contain the apex....
formed by the rotation of this normal around the Earth's axis.