The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
In mountaineering, a first ascent is the first successful, documented attainment of the top of a mountain, or the first to follow a particular climbing route. First mountain ascents are notable because they entail genuine exploration, with greater risks and recognition than climbing a route pioneered by others; the person who performs the first ascent is called the first ascensionist. In free climbing, a first ascent of a climbing route is the first successful, documented climb of a route without using equipment such as anchors or ropes for aiding progression or resting; the details of the first ascents of many prominent mountains are scanty or unknown. Today, first ascents are carefully recorded and mentioned in guidebooks. Overwhelmingly, the idea of a "first ascent" is a modern one in places such as Africa and the Americas with a history of colonialism. There may be little or no physical evidence or documentation about the climbing activities of indigenous peoples living near the mountain.
For example, the volcano Llullaillaco on the border of Argentina and Chile is known to have been climbed in the prehistoric period due to the presence of Incan artifacts at the summit, yet credit for the first recorded ascent is given to Chilean climbers Bión González and Juan Harseim, who summited in 1952. The term is used when referring to ascents made using a specific technique or taking a specific route, such as via the North Face, without ropes or without oxygen. In rock climbing, some of the earlier first ascents for difficult routes, involved a mix of free and aid climbing; as a result, purist free climbers have developed the designation first free ascent to acknowledge ascents intentionally made more challenging by using equipment for protection only. Second ascents are noteworthy in climbing circles involving improving on a pioneering route through lessons learned from it, experience which may span from technical improvements to having a better understanding of how much gear and provisions to take.
Some other "first ascents" could be recorded for particular routes. One is the First Winter Ascent, which is, as the name suggests, the first ascent made during winter season; this is most important where the climate of winter is a factor in increasing the difficulty grade of the route. In the Northern Hemisphere conventional winter ascents are made between December 21 and March 21 and are not related to the conditions. In the Himalayan area, although Nepal and China's winter season permits start on December 1, the conventional winter ascents begin on December 21. Another is the First Solo Ascent, the first ascent made by a single climber; this is most important on high-level rock climbing, when the climber has to provide his own security or when climbing without any protection at all. Another type of ascent known as FFA is the first female ascent. While not considered as important, this designation remains significant on some difficult, limit-pushing climbs, where the first female ascent may not happen until well after the FA, due to possible difficulties encountered by female physicality.
The term last ascent has been used to refer to an ascent of a mountain or face that has subsequently changed to such an extent – because of rockfall – that the route no longer exists. It can be used facetiously to refer to a climb, so unpleasant or unaesthetic that no one would willingly repeat the first ascent party's ordeal. List of first ascents Notable first free ascents List of first ascents in the Alps List of first ascents in the Himalaya Glossary of climbing terms Alpinist Magazine – Peter Mortimer's First Ascent, Issue 17
A summit is a point on a surface, higher in elevation than all points adjacent to it. The topographic terms acme, apex and zenith are synonymous; the term top is used only for a mountain peak, located at some distance from the nearest point of higher elevation. For example, a big massive rock next to the main summit of a mountain is not considered a summit. Summits near a higher peak, with some prominence or isolation, but not reaching a certain cutoff value for the quantities, are considered subsummits of the higher peak, are considered part of the same mountain. A pyramidal peak is an exaggerated form produced by ice erosion of a mountain top. Summit may refer to the highest point along a line, trail, or route; the highest summit in the world is Everest with height of 8844.43 m above sea level. The first official ascent was made by Sir Edmund Hillary, they reached the mountain`s peak in 1953. Whether a highest point is classified as a summit, a sub peak or a separate mountain is subjective; the UIAA definition of a peak is.
Otherwise, it's a subpeak. In many parts of the western United States, the term summit refers to the highest point along a road, highway, or railroad. For example, the highest point along Interstate 80 in California is referred to as Donner Summit and the highest point on Interstate 5 is Siskiyou Mountain Summit. A summit climbing differs from the common mountaineering. Summit expedition requires: 1+ year of training, a good physical shape, a special gear. Although a huge part of climber’s stuff can be left and taken at the base camps or given to porters, there is a long list of personal equipment. In addition to common mountaineers’ gear, Summit climbers need to take Diamox and bottles of oxygen. There are special requirements for crampons, ice axe, rappel device, etc. Geoid Hill – Landform that extends above the surrounding terrain Nadir Summit accordance Peak finder Summit Climbing Gear List
Sierra Peaks Section
The Sierra Peaks Section is a mountaineering society within the Angeles Chapter of the Sierra Club that serves to provide mountaineering activities for Sierra Club members in the Sierra Nevada, to honor mountaineers who have summited Sierra Nevada peaks. The Sierra Peaks Section was established in 1955; the Section maintains historic summit registers at Bancroft Library on the University of California, Berkeley campus. To become a member of the SPS, one must be a Sierra Club member and have climbed at least six peaks on the SPS List. For verification purposes, two of those ascents must be done on an official SPS trip. Accomplished members are award with emblems, with the following grades: Third List Completion Second List Completion First List Completion Master Emblem Senior Emblem EmblemUpon receiving one of the normal emblems, members may be recognized with one of the following additional emblems, which are not ranked: Geographic Emblem Explorer Emblem To the general public, they are most known for their peak bagging list, created in 1955, a product of the Sierra Club's long legacy of promoting climbing in the Sierra Nevada.
Completing the list is prestigious in American mountaineering circles, climbers who complete the list are cited as having done so. The list is divided into three levels of importance; the Emblem peaks are considered the most iconic peaks of the Sierra Nevada, to summit all of them is the goal of many peak baggers and alpinists. Mountaineers peaks are less notable peaks known for presenting mountaineering challenges. There are the numerous general peaks of lesser note; the list is an example of a subjective "decision by committee" list with the peaks on the list being determined by the Sierra Club. Peaks are added or removed from the list due to a variety of factors, such as accessibility and interest; the list is followed by thousands of hikers and has been noted in numerous books and guides on the Sierra Nevada. There are 15 Emblem peaks, 35 Mountaineers peaks, 197 general peaks, for a total of 247 peaks; the number of peaks is traditionally set at 248, the original number of peaks listed in 1955.
The elevations listed below are those described on the list, may not be the actual elevations of those peaks, although they are accurate to within 50 feet. Other peak bagging lists: New England Fifty Finest Adirondack High Peaks Secor, R. J.. The High Sierra: peaks, trail. Seattle, WA: Mountaineers Books. ISBN 978-0-89886-971-2. Official web site
In topography, prominence measures the height of a mountain or hill's summit relative to the lowest contour line encircling it but containing no higher summit within it. It is a measure of the independence of a summit. A peak's key col is a unique point on this contour line and the parent peak is some higher mountain, selected according to various objective criteria. There are at least two definitions of prominence: The prominence of a peak is the minimum height necessary to descend to get from the summit to any higher terrain, which can be calculated for a given peak in the following way: for every path connecting the peak to higher terrain, find the lowest point on the path. See Figure 1; the prominence of a peak is the height of the peak’s summit above the lowest contour line encircling it but containing no higher summit within it. This allows the prominence of points like Everest to be calculated, as long as a lowest point can be defined; the following mental exercise may illustrate the meaning of topographic prominence.
Imagine a peak and imagine that an imaginary sea level rises to the peak. Now lower the imaginary sea level and an imaginary island appears beneath your feet; the island will merge with other islands that emerge. The island will touch an island with a higher peak than the initial island The summit of that island is the parent peak of the summit, the point at which the two islands touch is the key col of the summit, the elevation rise from the key col to the summit is the topographic prominence of the summit; the parent peak may be either far from the subject peak. The summit of Mount Everest is the parent peak of Aconcagua at a distance of 17,755 km, as well as the parent of the South Summit of Mount Everest at a distance of 360 m; the key col may be close to the subject peak or far from it. The key col for Aconcagua, if sea level is disregarded, is the Bering Strait at a distance of 13,655 km; the key col for the South Summit of Mount Everest is about 100 m distant. Prominence is interesting to many mountaineers because it is an objective measurement, correlated with the subjective significance of a summit.
Peaks with low prominence are either subsidiary tops of some higher summit or insignificant independent summits. Peaks with high prominence tend to be the highest points around and are to have extraordinary views. Only summits with a sufficient degree of prominence are regarded as independent mountains. For example, the world's second-highest mountain is K2. While Mount Everest's South Summit is taller than K2, it is not considered an independent mountain because it is a sub-summit of the main summit. Many lists of mountains take topographic prominence as cutoff. John and Anne Nuttall's The Mountains of England and Wales uses a cutoff of 15 m, Alan Dawson's list of Marilyns uses 150 m.. In the contiguous United States, the famous list of "fourteeners" uses a cutoff of 300 ft / 91 m. In the U. S. 2000 ft of prominence has become an informal threshold that signifies that a peak has major stature. Lists with a high topographic prominence cutoff tend to favor isolated peaks or those that are the highest point of their massif.
While the use of prominence as a cutoff to form a list of peaks ranked by elevation is standard and is the most common use of the concept, it is possible to use prominence as a mountain measure in itself. This generates lists of peaks ranked by prominence, which are qualitatively different from lists ranked by elevation; such lists tend to emphasize isolated high peaks, such as range or island high points and stratovolcanoes. One advantage of a prominence-ranked list is that it needs no cutoff since a peak with high prominence is automatically an independent peak, it is common to define a peak's parent as a particular peak in the higher terrain connected to the peak by the key col. If there are many higher peaks there are various ways of defining which one is the parent, not based on geological or geomorphological factors; the "parent" relationship defines a hierarchy. For example, in Figure 1, the middle peak is a subpeak of the right peak, in turn a subpeak of the left peak, the highest point on its landmass.
In that example, there is no controversy over the hierarchy. These different definitions follow. A special case occurs for the highest point on an oceanic continent; some sources define no parent in this case. Called prominence island parentage, this is defined as follows. In figure 2 the key col of peak A is at the meeting place of two closed contours, one encircling A and the other containing at least one higher peak; the encirclement parent of A is the highest peak, inside this other contour. In terms of the
Geographic coordinate system
A geographic coordinate system is a coordinate system that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are chosen such that one of the numbers represents a vertical position and two or three of the numbers represent a horizontal position. A common choice of coordinates is latitude and elevation. To specify a location on a plane requires a map projection; the invention of a geographic coordinate system is credited to Eratosthenes of Cyrene, who composed his now-lost Geography at the Library of Alexandria in the 3rd century BC. A century 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 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, 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 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 a little before 1300. 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 the motion, while Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911.
In order to be unambiguous about the direction of "vertical" and the "horizontal" surface above which they are measuring, map-makers choose a reference ellipsoid with a given origin and orientation that best fits their need for the area they are mapping. They choose the most appropriate mapping of the spherical coordinate system onto that ellipsoid, called a terrestrial reference system or geodetic datum. 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. Points on the Earth's surface move relative to each other due to continental plate motion and diurnal Earth tidal movement caused by the Moon and the Sun; this daily movement can be as much as a metre. Continental movement can be up to 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 neighbouring 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. Examples of global datums include World Geodetic System, the default datum used for the Global Positioning System, the International Terrestrial Reference Frame, used for estimating continental drift and crustal deformation; the distance to Earth's center can be used both for deep positions and for positions in space. Local datums chosen by a national cartographical organisation include the North American Datum, the European ED50, the British OSGB36. Given a location, the datum provides the latitude ϕ and longitude λ. In the United Kingdom there are three common latitude and height systems in use. WGS 84 differs at Greenwich from the one used on published maps OSGB36 by 112 m; the military system ED50, used by NATO, differs from about 120 m to 180 m. The latitude and longitude on a map made against a local datum may not be the same as one obtained from a GPS receiver. Coordinates from the mapping system can sometimes be changed into another datum using a simple translation.
For example, to convert from ETRF89 to the Irish Grid add 49 metres to the east, subtract 23.4 metres from the north. More one datum is changed into any other datum using a process called Helmert transformations; this involves converting the spherical coordinates into Cartesian coordinates and applying a seven parameter transformation, converting back. In popular GIS software, data projected in latitude/longitude is represented as a Geographic Coordinate System. For example, data in latitude/longitude if the datum is the North American Datum of 1983 is denoted by'GCS North American 1983'; the "latitude" 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 the center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels, as they are parallel to the Equator and to each other; the North Pole is 90° N. The 0° parallel of latitude is designated the Equator, the fun