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67-882: Coordinates : 41°13′0.639″N 118°45′21.606″W / 41.21684417°N 118.75600167°W / 41.21684417; -118.75600167 Protected area in Nevada, United States Black Rock Desert IUCN category Ib ( wilderness area ) [REDACTED] BLM map of the Black Rock-High Rock NCA and 10 wilderness areas including Black Rock Desert Wilderness [REDACTED] [REDACTED] Location of Black Rock Desert Wilderness in Nevada Show map of Nevada [REDACTED] [REDACTED] Location of Black Rock Desert Wilderness in United States Show map of
134-532: A prime meridian at the westernmost known land, designated the Fortunate Isles , off the coast of western Africa around the Canary or Cape Verde Islands , and measured north or south of the island of Rhodes off Asia Minor . Ptolemy credited him with the full adoption of longitude and latitude, rather than measuring latitude in terms of the length of the midsummer day. Ptolemy's 2nd-century Geography used
201-646: A little before 1300; the text was translated into Latin at Florence by Jacopo d'Angelo around 1407. In 1884, the United States hosted the International Meridian Conference , attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich , England as the zero-reference line. The Dominican Republic voted against
268-416: A location often facetiously called Null Island . In order to use the theoretical definitions of latitude, longitude, and height to precisely measure actual locations on the physical earth, a geodetic datum must be used. A horizonal datum is used to precisely measure latitude and longitude, while a vertical datum is used to measure elevation or altitude. Both types of datum bind a mathematical model of
335-535: A longitudinal degree is 111.3 km. At 30° a longitudinal second is 26.76 m, at Greenwich (51°28′38″N) 19.22 m, and at 60° it is 15.42 m. On the WGS 84 spheroid, the length in meters of a degree of latitude at latitude ϕ (that is, the number of meters you would have to travel along a north–south line to move 1 degree in latitude, when at latitude ϕ ), is about The returned measure of meters per degree latitude varies continuously with latitude. Similarly,
402-402: A more unified bureau mission and recognized the value of the remaining public lands by declaring that these lands would remain in public ownership. The law directed that these lands be managed with a view toward "multiple use" defined as "management of the public lands and their various resource values so that they are utilized in the combination that will best meet the present and future needs of
469-670: A national cartographical organization include the North American Datum , the European ED50 , and the British OSGB36 . Given a location, the datum provides the latitude ϕ {\displaystyle \phi } and longitude λ {\displaystyle \lambda } . In the United Kingdom there are three common latitude, longitude, and height systems in use. WGS 84 differs at Greenwich from
536-590: A pilot project on the Pryor Mountains Wild Horse Range known as the Adopt-A-Horse initiative. The program took advantage of provisions in the WFRHBA to allow private "qualified" individuals to "adopt" as many horses as they wanted if they could show that they could provide adequate care for the animals. At the time, title to the horses remained permanently with the federal government. The pilot project
603-513: A regular and recurring presence on a vast amount of public lands, roads and recreation sites. They focus on the protection of natural and cultural resources, other BLM employees and visitors. Given the many locations of BLM public lands, these rangers use canines, helicopters, snowmobiles, dirt bikes and boats to perform their duties. By contrast BLM special agents are criminal investigators who plan and conduct investigations concerning possible violations of criminal and administrative provisions of
670-841: A simple translation may be sufficient. Datums may be global, meaning that they represent the whole Earth, or they may be local, meaning that they represent an ellipsoid best-fit to only a portion of the Earth. Examples of global datums include World Geodetic System (WGS 84, also known as EPSG:4326 ), the default datum used for the Global Positioning System , and the International Terrestrial Reference System and Frame (ITRF), used for estimating continental drift and crustal deformation . The distance to Earth's center can be used both for very deep positions and for positions in space. Local datums chosen by
737-500: A year, or 10 m in a century. A weather system high-pressure area can cause a sinking of 5 mm . Scandinavia is rising by 1 cm a year as a result of the melting of the ice sheets of the last ice age , but neighboring Scotland is rising by only 0.2 cm . These changes are insignificant if a local datum is used, but are statistically significant if a global datum is used. On the GRS 80 or WGS 84 spheroid at sea level at
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#1733085144055804-583: Is where Earth's equatorial radius a {\displaystyle a} equals 6,378,137 m and tan β = b a tan ϕ {\displaystyle \textstyle {\tan \beta ={\frac {b}{a}}\tan \phi }\,\!} ; for the GRS 80 and WGS 84 spheroids, b a = 0.99664719 {\textstyle {\tfrac {b}{a}}=0.99664719} . ( β {\displaystyle \textstyle {\beta }\,\!}
871-418: Is a spherical or geodetic coordinate system for measuring and communicating positions directly on Earth as latitude and longitude . It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms the basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system , the geographic coordinate system
938-689: Is an agency within the United States Department of the Interior responsible for administering U.S. federal lands . Headquartered in Washington, D.C. , the BLM oversees more than 247.3 million acres (1,001,000 km ) of land, or one-eighth of the United States's total landmass. The Bureau was created by Congress during the presidency of Harry S. Truman in 1946 by combining two existing agencies:
1005-746: Is known as the reduced (or parametric) latitude ). Aside from rounding, this is the exact distance along a parallel of latitude; getting the distance along the shortest route will be more work, but those two distances are always within 0.6 m of each other if the two points are one degree of longitude apart. Like any series of multiple-digit numbers, latitude-longitude pairs can be challenging to communicate and remember. Therefore, alternative schemes have been developed for encoding GCS coordinates into alphanumeric strings or words: These are not distinct coordinate systems, only alternative methods for expressing latitude and longitude measurements. Bureau of Land Management The Bureau of Land Management ( BLM )
1072-685: Is located within the Black Rock Desert – High Rock Canyon Emigrant Trails National Conservation Area , also managed by the BLM. See also [ edit ] Black Rock Desert-High Rock Canyon Emigrant Trails National Conservation Area List of largest wilderness areas in the United States References [ edit ] ^ Protected Planet Website - Retrieved March 28, 2023 ^ "Black Rock Desert Wilderness" . Geographic Names Information System . United States Geological Survey , United States Department of
1139-540: Is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid ), as different datums will yield different latitude and longitude values for the same location. The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene , who composed his now-lost Geography at
1206-546: Is not protected by a national park or monument designation. The BLM's May 30, 2019 statement proposed an additional 183,668 acres on "lands managed by the Canyon Country, Color Country, Green River, and West Desert districts" that would be listed for the quarterly oil and gas lease sale on September 10, 2019. In their May 2019, September lease offerings, the BLM said that they had "245 million acres of public land located primarily in 12 Western states, including Alaska" and across
1273-619: Is the SIG Sauer P320 chambered in 9mm which is replacing the SIG Sauer P226 /P229 both chambered in .40 S&W. The BLM manages free-roaming horses and burros on public lands in ten western states. Though they are feral , the agency is obligated to protect them under the Wild and Free-Roaming Horses and Burros Act of 1971 (WFRHBA). As the horses have few natural predators, populations have grown substantially. WFRHBA as enacted provides for
1340-530: Is the agency's largest ever purchase in the state. In 2024 the Department of the Interior has begun to advance a new rule according to which the Bureau of Land Management can distribute restoration leases and mitigation leases exactly in the same way as it distributes new leases for oil and gas drilling. The designed land will be used for nature conservation including use of indigenous knowledge. Established in 2000,
1407-731: Is the angle east or west of a reference meridian to another meridian that passes through that point. All meridians are halves of great ellipses (often called great circles ), which converge at the North and South Poles. The meridian of the British Royal Observatory in Greenwich , in southeast London, England, is the international prime meridian , although some organizations—such as the French Institut national de l'information géographique et forestière —continue to use other meridians for internal purposes. The prime meridian determines
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#17330851440551474-405: Is ultimately calculated from latitude and longitude, it is crucial that they clearly state the datum on which they are based. For example, a UTM coordinate based on WGS84 will be different than a UTM coordinate based on NAD27 for the same location. Converting coordinates from one datum to another requires a datum transformation such as a Helmert transformation , although in certain situations
1541-629: The Bureau of Land Management . It is located in the east arm of the Black Rock Desert playa east of the Black Rock Range and west of the Jackson Mountains . The wilderness has a land area of 314,829 acres, or 1,274.1 km. It is the largest U.S. designated wilderness area that is managed solely by the Bureau of Land Management, and the largest that is not located within a National Forest, National Park (or Preserve), or National Wildlife Refuge. It
1608-466: The Department of the Interior . It took several years for this new agency to integrate and reorganize. In the end, the Bureau of Land Management became less focused on land disposal and more focused on the long term management and preservation of the land. The agency achieved its current form by combining offices in the western states and creating a corresponding office for lands both east of and alongside
1675-701: The Grand Staircase–Escalante National Monument in southern Utah, the first of now 20 national monuments established on BLM lands and managed by the agency. The establishment of Grand Staircase–Escalante foreshadowed later creation of the BLM's National Landscape Conservation System in 2000. Use of the Antiquities Act authority, to the extent it effectively scuttled a coal mine to have been operated by Andalex Resources , delighted recreation and conservation enthusiasts but set up larger confrontations with state and local authorities. Under
1742-489: The Library of Alexandria in the 3rd century BC. A century later, Hipparchus of Nicaea improved on this system by determining latitude from stellar measurements rather than solar altitude and determining longitude by timings of lunar eclipses , rather than dead reckoning . In the 1st or 2nd century, Marinus of Tyre compiled an extensive gazetteer and mathematically plotted world map using coordinates measured east from
1809-673: The Mississippi River . As a matter of course, the BLM's emphasis fell on activities in the western states as most of the mining, land sales, and federally owned areas are located west of the Mississippi. BLM personnel on the ground have typically been oriented toward local interests, while bureau management in Washington are led by presidential guidance. By means of the Federal Land Policy and Management Act of 1976, Congress created
1876-698: The National Conservation Lands (formerly known as the National Landscape Conservation System), totaling about 36 million acres (150,000 km ). In addition the National Conservation Lands include nearly 2,400 miles of Wild and Scenic Rivers , and nearly 6,000 miles of National Scenic and Historic Trails . There are more than 63,000 oil and gas wells on BLM public lands. Total energy leases generated approximately $ 5.4 billion in 2013, an amount divided among
1943-574: The National Landscape Conservation System is overseen by the BLM. The National Landscape Conservation System lands constitute just about 12% of the lands managed by the BLM. Congress passed Title II of the Omnibus Public Land Management Act of 2009 (Public Law 111-11) to make the system a permanent part of the public lands protection system in the United States. By designating these areas for conservation,
2010-652: The Treasury , the states, and Native American groups. The BLM's roots go back to the Land Ordinance of 1785 and the Northwest Ordinance of 1787. These laws provided for the survey and settlement of the lands that the original Thirteen Colonies ceded to the federal government after the American Revolution . As additional lands were acquired by the United States from Spain , France and other countries,
2077-678: The United States Congress directed that they be explored, surveyed, and made available for settlement. During the Revolutionary War, military bounty land was promised to soldiers who fought for the colonies. After the war, the Treaty of Paris of 1783 , signed by the United States, the UK , France , and Spain , ceded territory to the United States. In the 1780s, other states relinquished their own claims to land in modern-day Ohio . By this time,
Black Rock Desert Wilderness - Misplaced Pages Continue
2144-715: The United States General Land Office and the Grazing Service . The agency manages the federal government's nearly 700 million acres (2,800,000 km ) of subsurface mineral estate located beneath federal, state and private lands severed from their surface rights by the Homestead Act of 1862 . Most BLM public lands are located in these 12 western states: Alaska , Arizona , California , Colorado , Idaho , Montana , Nevada , New Mexico , Oregon , Utah , Washington and Wyoming . The mission of
2211-636: The United States General Land Office as part of the Department of the Treasury to oversee the disposition of these federal lands. By the early 1800s, promised bounty land claims were finally fulfilled. In the 19th century, other bounty land and homestead laws were enacted to dispose of federal land. Several different types of patents existed. These include cash entry, credit, homestead, Indian, military warrants, mineral certificates, private land claims, railroads, state selections, swamps, town sites, and town lots. A system of local land offices spread throughout
2278-555: The American people." Since the Reagan administration in the 1980s, Republicans have often given priority to local control and to grazing, mining and petroleum production, while Democrats have more often emphasized environmental concerns even when granting mining and drilling leases. In September 1996, then President Bill Clinton used his authority under the Antiquities Act to establish
2345-495: The BLM and other statutes under the United States Code. Special agents are normally plain clothes officers who carry concealed firearms and other defensive equipment, make arrests, carry out complex criminal investigations, present cases for prosecution to local United States Attorneys and prepare investigative reports. Criminal investigators occasionally conduct internal and civil claim investigations. The current sidearm
2412-513: The BLM is "to sustain the health, diversity, and productivity of the public lands for the use and enjoyment of present and future generations." Originally BLM holdings were described as "land nobody wanted" because homesteaders had passed them by. All the same, ranchers hold nearly 18,000 permits and leases for livestock grazing on 155 million acres (630,000 km ) of BLM public lands. The agency manages 221 wilderness areas , 29 national monuments and some 636 other protected areas as part of
2479-615: The Biden administration, the BLM is working on a pilot project called "outcomes-based grazing", to see if cattle grazing can help achieve conservation, agency director Tracy Stone-Manning said in an interview published in April 2022. In June 2022, the BLM finalized two acquisitions in Colorado and Wyoming, acquiring over 40,000 acres of previously inaccessible land. The acquisition in Wyoming for 35,670 acres
2546-1165: The Colorado Lahontan Rye Patch South Fork Walker River Wild Horse Other Beaver Dam Berlin–Ichthyosaur Cathedral Gorge Cave Lake Dayton Echo Canyon Ice Age Fossils Kershaw–Ryan Lake Tahoe–Nevada Spring Mountain Ranch Spring Valley Valley of Fire Van Sickle Washoe Lake Previous Belmont Courthouse Floyd Lamb Walker Lake [REDACTED] Nevada portal Authority control databases [REDACTED] International VIAF National United States Israel Retrieved from " https://en.wikipedia.org/w/index.php?title=Black_Rock_Desert_Wilderness&oldid=1218539219 " Categories : IUCN Category Ib Black Rock Desert Protected areas of
2613-502: The Equator, one latitudinal second measures 30.715 m , one latitudinal minute is 1843 m and one latitudinal degree is 110.6 km. The circles of longitude, meridians, meet at the geographical poles, with the west–east width of a second naturally decreasing as latitude increases. On the Equator at sea level, one longitudinal second measures 30.92 m, a longitudinal minute is 1855 m and
2680-572: The Great Basin Wilderness areas of Nevada Protected areas of Humboldt County, Nevada Protected areas of Pershing County, Nevada Bureau of Land Management areas in Nevada Hidden categories: Pages using gadget WikiMiniAtlas Articles with short description Short description matches Wikidata Coordinates on Wikidata Geographic coordinate system A geographic coordinate system ( GCS )
2747-5973: The Interior . Retrieved 2009-05-04 . ^ "BLM Black Rock Desert-High Rock Canyon Emigrant Trails National Conservation Area" . Bureau of Land Management . Archived from the original on 2007-07-03 . Retrieved 2007-12-30 . External links [ edit ] Black Rock Desert Wilderness page at Wilderness.net v t e Black Rock Desert Geography Antelope Range Badger Mountains Black Rock Range Calico Hills Division Range Empire Fox Range Gerlach Granite Range Hannan Range High Rock Canyon Hills Hog Ranch Mountains Jackson Mountains Kamma Mountains Kings River Lake Lahontan Little High Rock Mountains Massacre Range Montana Mountains Pine Forest Range Poker Brown Mountains Quinn River Selenite Range Sentinel Hills Seven Troughs Range Sheephead Mountains Smoke Creek Desert Smoke Creek Mountains Yellow Hills [REDACTED] History Peter Lassen Applegate Trail Thrust2 land speed record (1983) Thrust SSC land speed record (1997) CSXT Space Shot (2004) Protected areas Black Rock–High Rock NCA Black Rock Desert Wilderness Calico Mountains Wilderness East Fork High Rock Canyon Wilderness High Rock Canyon Wilderness High Rock Lake Wilderness Little High Rock Canyon Wilderness North Black Rock Range Wilderness North Jackson Mountains Wilderness Pahute Peak Wilderness South Jackson Mountains Wilderness Transportation Empire Airport Old SR 34 Old SR 48 Old SR 49/Jungo Road SR 447 Uses and Activities Burning Man Camping Dooby Lane High Power Rocketry Land sailing Mining Rockhounding v t e Protected areas of Nevada Federal National Parks and Monuments Avi Kwa Ame NM ( BLM ) Basin and Range NM (BLM) Death Valley NP Gold Butte NM (BLM) Great Basin NP Tule Springs Fossil Beds NM National Recreation Areas Lake Mead Spring Mountains ( USFS ) National Forests Humboldt–Toiyabe Inyo Lake Tahoe Basin National Conservation Areas Black Rock Desert–High Rock Canyon Emigrant Trails Red Rock Canyon Sloan Canyon Wilderness Areas Alta Toquima Arc Dome Arrow Canyon Bald Mountain Becky Peak Big Rocks Black Canyon Black Rock Desert Boundary Peak Bridge Canyon Bristlecone Calico Mountains Clover Mountains Currant Mountain Death Valley Delamar Mountains East Fork High Rock Canyon East Humboldt Eldorado Far South Egans Fortification Range Goshute Canyon Government Peak Grant Range High Rock Canyon High Rock Lake High Schells Highland Ridge Ireteba Peaks Jarbidge Jimbilnan Jumbo Springs La Madre Mountains Lime Canyon Little High Rock Canyon Meadow Valley Range Mormon Mountains Mt Charleston Mt Grafton Mt Irish Mt Moriah Mt Rose Muddy Mountains Nellis Wash North Black Rock Range North Jackson Mountains North McCullough Pahute Peak Parsnip Peak Pinto Valley Quinn Canyon Rainbow Mountain Red Mountain Ruby Mountains Santa Rosa–Paradise Peak Shellback South Egan Range South Jackson Mountains South McCullough South Pahroc Range Spirit Mountain Table Mountain Tunnel Spring Wee Thump Joshua Tree Weepah Spring White Pine Range White Rock Range Worthington Mountains Wovoka National Wildlife Refuges Anaho Island Ash Meadows Desert Fallon Moapa Valley Pahranagat Ruby Lake Sheldon Stillwater State Historic Parks Elgin Schoolhouse Fort Churchill Mormon Station Old Las Vegas Mormon Fort Ward Charcoal Ovens Recreation Areas Big Bend of
Black Rock Desert Wilderness - Misplaced Pages Continue
2814-557: The National Parks and Public Land Legacy Restoration Fund each year for five years for needed maintenance for critical facilities and infrastructure in national parks, forests, wildlife refuges, recreation areas and American Indian schools. The Act also committed $ 900 million a year in royalties from offshore oil and natural gas to permanently fund the Land and Water Conservation Fund investments in conservation and recreation opportunities across
2881-599: The Trump administration, the BLM offered millions of acres of available Federal lands for 10-year leases for commercial development, potentially in oil and gas and mining, with the stated goal of "promoting American energy security". The BLM holds quarterly oil and gas lease sales. According to a June 18, 2018 article in The Atlantic , under the tenure of then- United States Secretary of the Interior , Ryan Zinke "practically gave away hundreds of thousands of acres of open land across
2948-519: The United States Location Black Rock Desert, Nevada, United States Coordinates 41°13′0.639″N 118°45′21.606″W / 41.21684417°N 118.75600167°W / 41.21684417; -118.75600167 Elevation 1,207 m (3,960 ft) Established 2000 Operator Bureau of Land Management The Black Rock Desert Wilderness is a U S Wilderness Area in Nevada under
3015-550: The United States another "700 million acres of sub-surface mineral estate" is under their management. The statement also said that these "diverse activities authorized on these lands generated $ 96 billion in sales of goods and services throughout the American economy in fiscal year 2017" while supporting over 468,000 jobs". On August 4, 2020, President Trump signed the Great American Outdoors Act into law, committing up to $ 1.9 billion from energy development revenues to
3082-475: The United States needed revenue to function and land was sold as a source of income for the government. In order to sell the land, surveys needed to be conducted. The Land Ordinance of 1785 instructed a geographer to oversee this work as undertaken by a group of surveyors. The first years of surveying were completed by trial and error; once the territory of Ohio had been surveyed, a modern public land survey system had been developed. In 1812, Congress established
3149-792: The United States. There are several herds of horses and burros roaming free on 26.9 million acres of range spread out in ten western states. It is essential to maintain a balance that keeps herd management land and animal population healthy. Some programs and partnerships include the Mustang Heritage Foundation, U.S. Border Patrol, Idaho 4H, Napa Mustang Days and Little Book Cliffs Darting Team. These partnerships help with adoption and animal population as well as education and raising awareness about wild horses and burros. In 2009, BLM opened Renewable Energy Coordination Offices in order to approve and oversee wind, solar, biomass, and geothermal projects on BLM-managed lands. The offices were located in
3216-766: The West, leasing it to energy companies for pennies on the dollar." The Salt Lake Tribune reported that in March 2019, the price per acre for leases near the Golden Spike National Historical Park , in Utah were "$ 1.50 an acre for the next two years". By September 11, 2018, the Department of Interior was offering 2.9 million acres to be leased to commercial operations including drilling for oil and gas and mining in New Mexico, Colorado, Arizona, and other states where public land
3283-450: The country. Also in August 2020, the BLM headquarters was relocated to Grand Junction, Colorado , by an order signed by Interior Secretary David Bernhardt . The relocation was praised by Republican Western politicians but criticized by Democrats as a move to weaken the agency through the loss of experienced staffers, who opted to stay in Washington, D.C. Some ranchers were concerned about
3350-508: The early successes of the adoption program, the BLM has struggled to maintain acceptable herd levels, as without natural predators, herd sizes can double every four years. As of 2014, there were more than 49,000 horses and burros on BLM-managed land, exceeding the BLM's estimated "appropriate management level" (AML) by almost 22,500. The Bureau of Land Management has implemented several programs and has developed partnerships as part of their management plan for preserving wild burros and horses in
3417-460: The far western Aleutian Islands . The combination of these two components specifies the position of any location on the surface of Earth, without consideration of altitude or depth. The visual grid on a map formed by lines of latitude and longitude is known as a graticule . The origin/zero point of this system is located in the Gulf of Guinea about 625 km (390 mi) south of Tema , Ghana ,
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#17330851440553484-440: The isolation of Grand Junction compared to other Western cities, having limited flights and road access. After the announcement, 87% of D.C.-based employees left, prompting former lead career BLM official Steve Ellis to state "the bureau lost a tremendous amount of expertise...[of] very seasoned people." On September 17, 2021, Secretary Deb Haaland announced that the headquarters would be moved back to Washington, D.C. Under
3551-859: The law directed the BLM to ensure these places are protected for future generations, similar to national parks and wildlife refuges . Source: BLM Resources and Statistics The BLM, through its Office of Law Enforcement & Security, functions as a federal law enforcement agency of the United States Government. BLM law enforcement rangers and special agents receive their training through Federal Law Enforcement Training Centers (FLETC). Full-time staffing for these positions approaches 300. Uniformed rangers enforce laws and regulations governing BLM lands and resources. As part of that mission, these BLM rangers carry firearms and defensive equipment, make arrests, execute search warrants, complete reports and testify in court. They seek to establish
3618-415: The length in meters of a degree of longitude can be calculated as (Those coefficients can be improved, but as they stand the distance they give is correct within a centimeter.) The formulae both return units of meters per degree. An alternative method to estimate the length of a longitudinal degree at latitude ϕ {\displaystyle \phi } is to assume a spherical Earth (to get
3685-473: The motion, while France and Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911. The latitude ϕ of a point on Earth's surface is the angle between the equatorial plane and the straight line that passes through that point and through (or close to) the center of the Earth. Lines joining points of the same latitude trace circles on
3752-516: The one used on published maps OSGB36 by approximately 112 m. The military system ED50 , used by NATO , differs from about 120 m to 180 m. Points on the Earth's surface move relative to each other due to continental plate motion, subsidence, and diurnal Earth tidal movement caused by the Moon and the Sun. This daily movement can be as much as a meter. Continental movement can be up to 10 cm
3819-404: The proper Eastern and Western Hemispheres , although maps often divide these hemispheres further west in order to keep the Old World on a single side. The antipodal meridian of Greenwich is both 180°W and 180°E. This is not to be conflated with the International Date Line , which diverges from it in several places for political and convenience reasons, including between far eastern Russia and
3886-415: The public rangelands by establishment of advisory boards that set grazing fees. The Oregon and California Revested Lands Sustained Yield Management Act of 1937, commonly referred as the O&C Act, required sustained yield management of the timberlands in western Oregon. In 1946, the Grazing Service was merged with the United States General Land Office to form the Bureau of Land Management within
3953-522: The removal of excess animals; the killing of lame, old, or sick animals; the private placement or adoption of excess animals; and even the killing of healthy animals if range management required it. The killing of healthy or unhealthy horses has almost never occurred. Pursuant to the Public Rangelands Improvement Act of 1978 , the BLM has established 179 "herd management areas" (HMAs) covering 31.6 million acres (128,000 km ) acres where feral horses can be found on federal lands. In 1973, BLM began
4020-430: The same datum will obtain the same location measurement for the same physical location. However, two different datums will usually yield different location measurements for the same physical location, which may appear to differ by as much as several hundred meters; this not because the location has moved, but because the reference system used to measure it has shifted. Because any spatial reference system or map projection
4087-484: The same prime meridian but measured latitude from the Equator instead. After their work was translated into Arabic in the 9th century, Al-Khwārizmī 's Book of the Description of the Earth corrected Marinus' and Ptolemy's errors regarding the length of the Mediterranean Sea , causing medieval Arabic cartography to use a prime meridian around 10° east of Ptolemy's line. Mathematical cartography resumed in Europe following Maximus Planudes ' recovery of Ptolemy's text
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#17330851440554154-486: The shape of the earth (usually a reference ellipsoid for a horizontal datum, and a more precise geoid for a vertical datum) to the earth. Traditionally, this binding was created by a network of control points , surveyed locations at which monuments are installed, and were only accurate for a region of the surface of the Earth. Some newer datums are bound to the center of mass of the Earth. This combination of mathematical model and physical binding mean that anyone using
4221-406: The surface of Earth called parallels , as they are parallel to the Equator and to each other. The North Pole is 90° N; the South Pole is 90° S. The 0° parallel of latitude is designated the Equator , the fundamental plane of all geographic coordinate systems. The Equator divides the globe into Northern and Southern Hemispheres . The longitude λ of a point on Earth's surface
4288-439: The territories, patenting land that was surveyed via the corresponding Office of the Surveyor General of a particular territory. This pattern gradually spread across the entire United States. The laws that spurred this system with the exception of the General Mining Law of 1872 and the Desert Land Act of 1877 have since been repealed or superseded. In the early 20th century, Congress took additional steps toward recognizing
4355-399: The value of the assets on public lands and directed the Executive Branch to manage activities on the remaining public lands. The Mineral Leasing Act of 1920 allowed leasing, exploration, and production of selected commodities, such as coal , oil , gas , and sodium to take place on public lands. The Taylor Grazing Act of 1934 established the United States Grazing Service to manage
4422-445: The width per minute and second, divide by 60 and 3600, respectively): where Earth's average meridional radius M r {\displaystyle \textstyle {M_{r}}\,\!} is 6,367,449 m . Since the Earth is an oblate spheroid , not spherical, that result can be off by several tenths of a percent; a better approximation of a longitudinal degree at latitude ϕ {\displaystyle \phi }
4489-457: Was so successful that BLM allowed it to go nationwide in 1976. The Adopt-a-Horse program quickly became the primary method of removing excess feral horses from BLM land given the lack of other viable methods. The BLM also uses limited amounts of contraceptives in the herd, in the form of PZP vaccinations; advocates say that additional use of these vaccines would help to diminish the excess number of horses currently under BLM management. Despite
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