The meridian 100° west of the

Prime Meridian A prime meridian is an arbitrarily chosen meridian (geography), meridian (a line of longitude) in a geographic coordinate system at which longitude is defined to be 0°. On a spheroid, a prime meridian and its anti-meridian (the 180th meridian ...

Greenwich Greenwich ( , , ) is an List of areas of London, area in south-east London, England, within the Ceremonial counties of England, ceremonial county of Greater London, east-south-east of Charing Cross. Greenwich is notable for its maritime hi ...

is a line of

longitude Longitude (, ) is a geographic coordinate that specifies the east- west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek lett ...

that extends from the

North Pole The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere where the Earth's rotation, Earth's axis of rotation meets its surface. It is called the True North Pole to distingu ...

across the

Arctic Ocean The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, ...

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

, the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

, the

Southern Ocean The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the world ocean, generally taken to be south of 60th parallel south, 60° S latitude and encircling Antarctica. With a size of , it is the seco ...

, and

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

to the

South Pole The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is the point in the Southern Hemisphere where the Earth's rotation, Earth's axis of rotation meets its surface. It is called the True South Pole to distinguish ...

. The 100th meridian west forms a

great circle In mathematics, a great circle or orthodrome is the circular intersection of a sphere and a plane passing through the sphere's center point. Discussion Any arc of a great circle is a geodesic of the sphere, so that great circles in spher ...

with the 80th meridian east. In the United States, this meridian roughly marks the boundary between the

semi-arid climate A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of se ...

in the west and the humid continental and

humid subtropical climate A humid subtropical climate is a subtropical -temperate climate type, characterized by long and hot summers, and cool to mild winters. These climates normally lie on the southeast side of all continents (except Antarctica), generally between ...

s in the east and is used as shorthand to refer to that arid-humid boundary. The meridian coincides with the approximate center of the continental United States, and is featured prominently on the cover of the

Charter of the United Nations The Charter of the United Nations is the foundational treaty of the United Nations (UN). It establishes the purposes, governing structure, and overall framework of the UN system, including its six principal organs: the Secretariat, the G ...

From Pole to Pole

Starting at the

and heading south to the

, the 100th meridian west passes through: :

United States

In the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

the meridian 100° west of Greenwich forms the eastern border of the Texas panhandle with

Oklahoma Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northea ...

(which traces its origin to the Adams-Onís Treaty in 1819 which settled the border between

New Spain New Spain, officially the Viceroyalty of New Spain ( ; Nahuatl: ''Yankwik Kaxtillan Birreiyotl''), originally the Kingdom of New Spain, was an integral territorial entity of the Spanish Empire, established by Habsburg Spain. It was one of several ...

and the United States between the Red River and

Arkansas River The Arkansas River is a major tributary of the Mississippi River. It generally flows to the east and southeast as it traverses the U.S. states of Colorado, Kansas, Oklahoma, and Arkansas. The river's source basin lies in Colorado, specifically ...

). Dodge City, Kansas lies exactly at the intersection of the Arkansas River and the 100th meridian. As first noted by John Wesley Powell in the 1870s, there is a big difference in rainfall by the different sides of the meridian. In the central

Great Plains The Great Plains is a broad expanse of plain, flatland in North America. The region stretches east of the Rocky Mountains, much of it covered in prairie, steppe, and grassland. They are the western part of the Interior Plains, which include th ...

, it roughly marks the western boundary of the normal reach of moist air from the

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

, and the approximate boundary (although some areas do push the boundary slightly farther east) between the

to the west and the humid continental (north of about 37°N) and humid subtropical (south of about 37°N) climates to the east. West of the meridian, raising livestock is much more economically important than east of it, and what

agriculture Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created ...

does exist relies heavily on irrigation. Historically, the meridian has often been taken as a rough boundary between the eastern and western United States. White settlement, spreading westward after the

American Civil War The American Civil War (April 12, 1861May 26, 1865; also known by Names of the American Civil War, other names) was a civil war in the United States between the Union (American Civil War), Union ("the North") and the Confederate States of A ...

, settled the area around this meridian during the 1870s. A sign across U.S. Highway 30 in Cozad, Nebraska, marks the place where the 100th meridian intersects with the routes of the

Oregon Trail The Oregon Trail was a east–west, large-wheeled wagon route and Westward Expansion Trails, emigrant trail in North America that connected the Missouri River to valleys in Oregon Territory. The eastern part of the Oregon Trail crossed what ...

, Pony Express,

transcontinental railroad A transcontinental railroad or transcontinental railway is contiguous rail transport, railroad trackage that crosses a continent, continental land mass and has terminals at different oceans or continental borders. Such networks may be via the Ra ...

, and the Lincoln Highway.

In popular culture

The song " At the Hundredth Meridian" by

The Tragically Hip The Tragically Hip, often referred to simply as the Hip, was a Canadian rock band formed in Kingston, Ontario in 1984, consisting of vocalist Gord Downie, guitarist Paul Langlois, guitarist Rob Baker (known as Bobby Baker until 1994), bassis ...

is about the 100th meridian west, specifically in Canada, and how it has traditionally been considered "where the

begin."

References

External links

* https://www.earthmagazine.org/article/dividing-line-past-present-and-future-100th-meridian {{DEFAULTSORT:100th Meridian West w100 meridian west Borders of Oklahoma Borders of Texas

From Pole to Pole

United States

In popular culture

See also

References

External links