1.
Western United States
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The Western United States, commonly referred to as the American West, the Far West, or simply the West, traditionally refers to the region comprising the westernmost states of the United States. Because European settlement in the U. S. expanded westward after its founding, prior to about 1800, the crest of the Appalachian Mountains was seen as the western frontier. Since then, the frontier moved westward and eventually lands west of the Mississippi River came to be referred to as the West. The West contains several major biomes, the Western U. S. is the largest region of the country, covering more than half the land area of the United States. Given this expansive and diverse geography it is no wonder the region is difficult to specifically define, a majority of the historian respondents placed the eastern boundary of the West east of the Census definition out on the eastern edge of the Great Plains or on the Mississippi River. The survey respondents as a whole showed just how little agreement there was on the boundaries of the West, within a region as large and diverse as the Western United States, smaller areas with more closely shared demographics and geography have developed as subregions. Meanwhile, the states of Idaho, Montana, Oregon and Washington can be considered part of the Northwest or Pacific Northwest, West Texas in the Chihuahuan Desert may be considered as part of the Western U. S. Fort Worth has long laid claim to be Where the West Begins, the West is still one of the most sparsely settled areas in the United States with 49.5 inhabitants per square mile. Only Texas with 78.0 inhabitants/sq mi, Washington with 86.0 inhabitants/sq mi. and California with 213.4 inhabitants/sq mi. exceed the national average of 77.98 inhabitants/sq mi. The entire Western region has also strongly influenced by European, Hispanic or Latino, Asian and Native Americans. African and European Americans, however, continue to wield a stronger political influence because of the rates of citizenship and voting among Asians. The West also contains much of the Native American population in the U. S. particularly in the reservations in the Mountain. The Western United States has a sex ratio than any other region in the United States. Because the tide of development had not yet reached most of the West when conservation became an issue, agencies of the federal government own. National parks are reserved for activities such as fishing, camping, hiking, and boating, but other government lands also allow commercial activities like ranching, logging. The largest city in the region is Los Angeles, located on the West Coast, Other West Coast cities include San Diego, San Bernardino, San Jose, San Francisco, Oakland, Bakersfield, Sacramento, Seattle, Tacoma, and Portland. Prominent cities in the Mountain States include Denver, Colorado Springs, Phoenix, Tucson, Albuquerque, Las Vegas, Salt Lake City, Boise, El Paso, and Cheyenne. Along the Pacific Ocean coast lie the Coast Ranges, which and they collect a large part of the airborne moisture moving in from the ocean
2.
Miocene
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The Miocene is the first geological epoch of the Neogene Period and extends from about 23.03 to 5.333 million years ago. The Miocene was named by Sir Charles Lyell and its name comes from the Greek words μείων and καινός and means less recent because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene Epoch and is followed by the Pliocene Epoch, the earth went from the Oligocene through the Miocene and into the Pliocene, with the climate slowly cooling towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event, the apes arose and diversified during the Miocene, becoming widespread in the Old World. By the end of this epoch, the ancestors of humans had split away from the ancestors of the chimpanzees to follow their own evolutionary path, as in the Oligocene before it, grasslands continued to expand and forests to dwindle in extent. In the Miocene seas, kelp forests made their first appearance, the plants and animals of the Miocene were fairly modern. The Miocene faunal stages from youngest to oldest are typically named according to the International Commission on Stratigraphy, Two subdivisions each form the lower, middle, continents continued to drift toward their present positions. Mountain building took place in western North America, Europe, both continental and marine Miocene deposits are common worldwide with marine outcrops common near modern shorelines. Well studied continental exposures occur in the North American Great Plains, India continued to collide with Asia, creating dramatic new mountain ranges. The Tethys Seaway continued to shrink and then disappeared as Africa collided with Eurasia in the Turkish–Arabian region between 19 and 12 Ma. The subsequent uplift of mountains in the western Mediterranean region and a fall in sea levels combined to cause a temporary drying up of the Mediterranean Sea near the end of the Miocene. The global trend was towards increasing aridity caused primarily by global cooling reducing the ability of the atmosphere to absorb moisture, climates remained moderately warm, although the slow global cooling that eventually led to the Pleistocene glaciations continued. Although a long-term cooling trend was well underway, there is evidence of a period during the Miocene when the global climate rivalled that of the Oligocene. The Miocene warming began 21 million years ago and continued until 14 million years ago, by 8 million years ago, temperatures dropped sharply once again, and the Antarctic ice sheet was already approaching its present-day size and thickness. Greenland may have begun to have large glaciers as early as 7 to 8 million years ago, life during the Miocene Epoch was mostly supported by the two newly formed biomes, kelp forests and grasslands. This allows for more grazers, such as horses, rhinoceroses, ninety five percent of modern plants existed by the end of this epoch. The higher organic content and water retention of the deeper and richer grassland soils, with long term burial of carbon in sediments, produced a carbon and this, combined with higher surface albedo and lower evapotranspiration of grassland, contributed to a cooler, drier climate. The expansion of grasslands and radiations among terrestrial herbivores correlates to fluctuations in CO2
3.
Snake Range
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The Snake Range is a mountain range in White Pine County, Nevada, United States. The south-central portion of the range is included within Great Basin National Park, the range reaches a maximum elevation of 13,065 feet at the summit of Wheeler Peak, the tallest independent mountain within Nevada and the second highest point within the state. The range also contains four of the five highest mountain peaks in Nevada, typical of other ranges in the Basin and Range Province, the Snake Range runs in a north-south direction, for approximately 60 miles. To the west are Spring Valley and the Schell Creek Range, and to the east across the Utah border are Snake Valley, Sacramento Pass is where U. S. Route 6-50, the Loneliest Highway in America, crosses the range. It is the means of eastbound access to this part of eastern Nevada. Great Basin National Park is located in the section of the Snake Range. Established in 1986, it protects the unique geologic and habitat features of the range and Great Basin Desert. The southern section includes the natural rock Lexington Arch. Several large groves of ancient Great Basin Bristlecone Pine trees thrive in the Great Basin montane forests of the higher elevations. The higher elevations of the Snake Range in the section are protected by the Mount Moriah Wilderness Area. The Snake Range includes two groups of peaks, the southern section rises quickly from a point near the border with Lincoln County, reaching the summit of Granite Peak just 10 miles to the north. From there northwards the range continues to rise, passing Lincoln Peak, Mt. Washington, Pyramid Peak, Baker Peak and it finally reaching its apex at Wheeler Peak. North of Wheeler Peak the range begins to drop, reaching 7,154 feet at Sacramento Pass, Sacramento Pass is where the more remote northern section of the range begins. In just 12 miles the range rises past Silver Creek Canyon, to the north of this peak is an unusual formation, a flat plateau of sub-alpine tundra called The Table, covering about 2 square miles at an elevation of 11,000 feet. A grove of ancient Great Basin Bristlecone Pines grows on this plateau near the peak, north of The Table is another unusual geologic feature. Deadman Creek and Smith Creek, draining eastward into Snake Valley, the mouth of this canyon lies below 3, 000-foot cliffs,6,000 feet below and 6 miles away from the summit of Mt. Moriah
4.
White Mountains (California)
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The White Mountains of California and Nevada are a triangular fault-block mountain range facing the Sierra Nevada across the upper Owens Valley. They extend for approximately 60 mi as an elevated plateau about 20 mi wide on the south. The ranges broad southern end is near the community of Big Pine, the narrow northern end is at Montgomery Pass, where U. S. Route 6 crosses. The range lies within the section of the Inyo National Forest. Middle slopes from 6,500 to 8,200 ft have somewhat denser stands of piñon pine and these upper and lower conifer zones are often separated by a zone of mountain mahogany brush. Various subspecies of sagebrush extend from surrounding valleys to the alpine zone. A bristlecone pine in the part of the range is the oldest known living tree in the world. Pine nuts from piñon pine stands were harvested as a staple food by Paiute Indians whose descendants still live in adjacent valleys. The White Mountains also have small remnant groves of pine, Jeffrey pine, ponderosa pine, Sierra juniper. A number of plant species are endemic to the White Mountains, fauna include two herds of bighorn sheep, mule deer, marmots and feral horses. Permanent streams have no fish, but there are naturalized populations of trout including rare Paiute cutthroat trout which is protected from angling. Birds include Clarks nutcracker and other Corvidae which eat and cache pine nuts, cattle from ranches in surrounding valleys are still grazed under permit as high as the alpine zone. Historically sheep were grazed in large numbers, introducing diseases from which the native Bighorn Sheep populations are still slowly recovering. Before European colonization of surrounding valleys in the mid 19th century, Paiute Indians occupied summer hunting camps up to about 13,100 ft, the highest point in the range is White Mountain Peak, which at 14,252 ft is the third-highest summit in California. This peak is actually an extinct volcano rising about 1,600 ft above the plateau surface, the summit is composed of Mesozoic metavolcanic rock – lava lifted and melted by rising granite. The volcano itself is long since gone, the White Mountains are the highest range completely inside the Great Basin, although the adjacent Sierra Nevada Range along the basins western edge has two higher summits. The entire range is within the Inyo National Forest, a four-wheel drive road reaches the summit from the south to service the summit laboratory of the White Mountain Research Station. The road is normally gated seven miles from the summit at an elevation of 11,680 ft, the bench includes Mt. Hogue at 12,743 ft. and further north Mt. Dubois at 13,559 ft. the high point on the plateau
5.
Sandia Mountains
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The Sandia Mountains are a mountain range located in Bernalillo and Sandoval counties, immediately to the east of the city of Albuquerque in New Mexico in the southwestern United States. The range is largely within the Cibola National Forest, and part of the range is protected as the Sandia Mountain Wilderness and its highest point is Sandia Crest,10,678 feet. Sandía means watermelon in Spanish, and is believed to be a reference to the reddish color of the mountains at sunset. Also, when viewed from the west, the profile of the mountains is a ridge, with a thin zone of green conifers near the top. He also notes that the Sandia Pueblo Indians call the mountain Bien Mur, the range measures approximately 17 miles north-south, and the width in the east-west direction varies from 4 to 8 miles. The west side of the range is steep and rugged, with a number of rock walls. The east side has a gentler slope, the Sandias are part of a single larger geologic unit, the Sandia-Manzano Mountains. The other part consists of the Manzano Mountains which lie to the south of the Sandias. The two ranges are separated by Tijeras Canyon, which leads to an important pass, the canyon is traversed by Interstate 40. The Sandias are the highest range in the vicinity, and are well-separated from the higher Sangre de Cristo Mountains. This gives Sandia Crest a relatively high topographic prominence of 4,098 ft. Lying to the east and northeast of the Sandias are two ranges, the Ortiz Mountains and the San Pedro Mountains. The Sandia Mountains are home to the second longest tramway. Over this distance the tram cars ascend over 4,000 feet, the average speed of the tram car is 12 mph, and the length of the ride is approximately 15 minutes. The current longest tramway as of 2010 is in Armenia, the Sandia Mountains are a fault block range, on the eastern edge of the Rio Grande Rift Valley. The Sandias were uplifted in the last ten years as part of the formation of the Rio Grande Rift. They form the boundary of the Albuquerque Basin. The core of the consists of Sandia granite, approximately 1.5 billion years old. This is topped by a thin layer of sedimentary rock of Pennsylvanian age
6.
Mount Whitney
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Mount Whitney is the highest summit in the contiguous United States and the Sierra Nevada, with an elevation of 14,505 feet. The west slope of the mountain is in Sequoia National Park, the east slope is in the Inyo National Forest in Inyo County. The summit of Whitney is on the Sierra Crest and the Great Basin Divide and it lies near many of the highest peaks of the Sierra Nevada. The peak rises dramatically above the Owens Valley, sitting 10,778 feet or just over two miles above the town of Lone Pine 15 miles to the east, in the Owens Valley. It rises more gradually on the west side, lying only about 3,000 feet above the John Muir Trail at Guitar Lake, the mountain is partially dome-shaped, with its famously jagged ridges extending to the sides. Mount Whitney is above the line and has an alpine climate. Very few plants grow near the summit, one example is the Skypilot, the only animals are transient, such as the butterfly Parnassius phoebus and the gray-crowned rosy finch. The mountain is the highest point on the Great Basin Divide, waterways on the west side of the peak flow into Whitney Creek, which flows into the Kern River. The Kern River terminates in the Tulare Basin, during very wet years, water overflows from the Tulare Basin into the San Joaquin River which flows to the Pacific Ocean. From the east, water from Mount Whitney flows to Lone Pine Creek, which joins the Owens River, which in turn terminates at Owens Lake, the estimated elevation of the summit of Mount Whitney has changed over the years. The technology of elevation measurement has become refined and, more importantly. The peak was commonly said to be at 14,494 ft, an older plaque on the summit reads elevation 14,496.811 feet but this was estimated using the older vertical datum from 1929. Since then the shape of the Earth has been estimated more accurately, using a new vertical datum established in 1988 the benchmark is now estimated to be at 14,505 ft. The rise is caused by a fault system that runs along the eastern base of the Sierra. Thus, the granite that forms Mount Whitney is the same as the granite that forms the Alabama Hills, the raising of Whitney is due to the same geological forces that cause the Basin and Range Province, the crust of much of the intermontane west is slowly being stretched. The granite that forms Mount Whitney is part of the Sierra Nevada batholith, in Cretaceous time, masses of molten rock that originated from subduction rose underneath what is now Whitney and solidified underground to form large expanses of granite. In July 1864, the members of the California Geological Survey named the peak after Josiah Whitney, during the same expedition, geologist Clarence King attempted to climb Whitney from its west side, but stopped just short. In 1871, King returned to climb what he believed to be Whitney, upon learning of his mistake in 1873, King finally completed his own first ascent of Whitney, but did so a month too late to claim the first recorded ascent
7.
Pico de Orizaba
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Pico de Orizaba, also known as Citlaltépetl, is a stratovolcano, the highest mountain in Mexico and the third highest in North America, after Denali of the United States and Mount Logan of Canada. It rises 5,636 metres above sea level in the end of the Trans-Mexican Volcanic Belt. The volcano is currently dormant but not extinct, with the last eruption taking place during the 19th century and it is the second most prominent volcanic peak in the world after Africas Mount Kilimanjaro. Pico de Orizaba overlooks the valley and city of Orizaba, from which it gets its name, the name Citlaltépetl is not used by Nahuatl speakers of the Orizaba area, who instead call it Istaktepetl, or White Mountain. In the earliest mention of the volcano, it was referred to by the natives during the Pre-Columbian Era as Poyautécatl, Citlaltépetl was the common name in the Náhuatl language when the Spanish arrived in Mexico. Citlaltépetl comes from the Náhuatl citlalli and tepētl and thus means Star Mountain and this name is thought to be based on the fact that the snow-covered peak can be seen year round for hundreds of kilometers throughout the region. A legend from the city of Coscomatepec tells of how the planet Venus can be seen settling into the crater of Citlaltépetl, during the colonial era, the volcano was also known as Cerro de San Andrés due to the nearby settlement of San Andrés Chalchicomula at its base. A third name, Poyauhtecatl, which means the one that colors or illuminates, has also been recorded and this name was given by the Tlaxcaltecas in memory of their lost country. The peak of Citlaltépetl rises dramatically to an elevation of 5,636 m above sea level, it has a topographic prominence of 4,922 m. Regionally dominant, Pico de Orizaba is the highest peak in Mexico, Orizaba is ranked 7th in the world in topographic prominence. It is the second most prominent volcanic peak in the world after Africas Mount Kilimanjaro, the topography of Pico de Orizaba is asymmetrical from the center of the crater, the eastern face is the steepest side of the volcano and the northwestern face the most gradual side. The gradual slopes of the face of the volcano allows for the presence of large glaciers and is the most traveled route to take for hikers traveling to the summit. Pico de Orizaba is one of three volcanoes in México that continue to support glaciers and is home to the largest glacier in Mexico. Orizaba has nine known glaciers, Gran Glaciar Norte, Lengua del Chichimeco, Jamapa, Toro, Glaciar de la Barba, Noroccidental, Occidental, Suroccidental, the equilibrium line altitude is not known for Orizaba. Snow on the south and southeast sides of the volcano melts quickly because of solar radiation, the insolation angle and wind redeposition on the northwest and north sides allow for constant accumulation of snow providing a source for the outlet glaciers. On the north side of Orizaba, the Gran Glaciar Norte fills the elongated highland basin and is the source for seven outlet glaciers. The main glacier extends 3.5 km north of the rim, has a surface area of about 9.08 km2 descending from 5,650 m to about 5,000 m. It has an irregular and stepped profile that is caused in part by the configuration of the bedrock
8.
California
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California is the most populous state in the United States and the third most extensive by area. Located on the western coast of the U. S, California is bordered by the other U. S. states of Oregon, Nevada, and Arizona and shares an international border with the Mexican state of Baja California. Los Angeles is Californias most populous city, and the second largest after New York City. The Los Angeles Area and the San Francisco Bay Area are the nations second- and fifth-most populous urban regions, California also has the nations most populous county, Los Angeles County, and its largest county by area, San Bernardino County. The Central Valley, an agricultural area, dominates the states center. What is now California was first settled by various Native American tribes before being explored by a number of European expeditions during the 16th and 17th centuries, the Spanish Empire then claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its war for independence. The western portion of Alta California then was organized as the State of California, the California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom. If it were a country, California would be the 6th largest economy in the world, fifty-eight percent of the states economy is centered on finance, government, real estate services, technology, and professional, scientific and technical business services. Although it accounts for only 1.5 percent of the states economy, the story of Calafia is recorded in a 1510 work The Adventures of Esplandián, written as a sequel to Amadis de Gaula by Spanish adventure writer Garci Rodríguez de Montalvo. The kingdom of Queen Calafia, according to Montalvo, was said to be a land inhabited by griffins and other strange beasts. This conventional wisdom that California was an island, with maps drawn to reflect this belief, shortened forms of the states name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, various estimates of the native population range from 100,000 to 300,000. The Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups also were diverse in their organization with bands, tribes, villages. Trade, intermarriage and military alliances fostered many social and economic relationships among the diverse groups, the first European effort to explore the coast as far north as the Russian River was a Spanish sailing expedition, led by Portuguese captain Juan Rodríguez Cabrillo, in 1542. Some 37 years later English explorer Francis Drake also explored and claimed a portion of the California coast in 1579. Spanish traders made unintended visits with the Manila galleons on their trips from the Philippines beginning in 1565
9.
Badwater Basin
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Badwater Basin is an endorheic basin in Death Valley National Park, Death Valley, Inyo County, California, noted as the lowest point in North America, with an elevation of 282 ft below sea level. Mount Whitney, the highest point in the contiguous 48 United States, is only 84.6 miles to the north west. The site itself consists of a small spring-fed pool of bad water next to the road in a sink, the pool does have animal and plant life, including pickleweed, aquatic insects, and the Badwater snail. Adjacent to the pool, where water is not always present at the surface, repeated freeze–thaw, the pool is not the lowest point of the basin, the lowest point is several miles to the west and varies in position, depending on rainfall and evaporation patterns. The salt flats are hazardous to traverse, and so the sign marking the low point is at the pool instead, the basin was considered the lowest elevation in the Western Hemisphere until the discovery of Laguna del Carbón in Argentina at −344 ft. At Badwater Basin, significant rainstorms flood the valley bottom periodically, newly formed lakes do not last long though, because the 1.9 in of average rainfall is overwhelmed by a 150 in annual evaporation rate. This is the greatest evaporation potential in the United States, meaning that a 12 ft lake could dry up in a single year, when the basin is flooded, some of the salt is dissolved, it is redeposited as clean crystals when the water evaporates. A popular site for tourists is the sign marking sea level on the cliff above the Badwater Basin, numerous evaporation cycles and a lack of outflow caused an increasing hypersalinity, typical for endorheic bodies of water. Over time, this hypersalinization, combined with sporadic rainfall and occasional aquifer intrusion, has resulted in periods of briny soup, or salty pools, on the lowest parts of Death Valleys floor. Salts began to crystallize, coating the surface with the thick crust, ranging from 3 to 60 in, Death Valley pupfish List of elevation extremes by country List of elevation extremes by region John McKinney, Californias Desert Parks, A Day Hikers Guide. Wilderness Press 2006, ISBN 0-89997-389-2, S. 54–55 Don J. Easterbrook, geological Society of America 2003, ISBN 94-592-0504-6, S. 63–64 Badwater Basin in the Encyclopædia Britannica
10.
Ecoregion
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An ecoregion is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than an ecozone. All three of these are less or greater than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, the biodiversity of flora, fauna and ecosystems that characterise an ecoregion tends to be distinct from that of other ecoregions. Three caveats are appropriate for all bio-geographic mapping approaches, firstly, no single bio-geographic framework is optimal for all taxa. Ecoregions reflect the best compromise for as many taxa as possible, secondly, ecoregion boundaries rarely form abrupt edges, rather, ecotones and mosaic habitats bound them. Thirdly, most ecoregions contain habitats that differ from their assigned biome, biogeographic provinces may originate due to various barriers. Some physical, some climatic and some ocean chemical related, the history of the term is somewhat vague as it was used in many contexts, forest classifications, biome classifications, biogeographic classifications, etc. The concept of ecoregion of Bailey gives more importance to ecological criteria, while the WWF concept gives more importance to biogeography, there is significant, but not absolute, spatial correlation among these characteristics, making the delineation of ecoregions an imperfect science. Such transition zones are called ecotones, Ecoregions can be categorized using an algorithmic approach or a holistic, “weight-of-evidence” approach where the importance of various factors may vary. An example of the approach is Robert Bailey’s work for the U. S. The intended purpose of ecoregion delineation may affect the method used, according to WWF, the boundaries of an ecoregion approximate the original extent of the natural communities prior to any major recent disruptions or changes. WWF has identified 867 terrestrial ecoregions, and approximately 450 freshwater ecoregions across the Earth, the use of the term ecoregion is an outgrowth of a surge of interest in ecosystems and their functioning. In particular, there is awareness of issues relating to spatial scale in the study and it is widely recognized that interlinked ecosystems combine to form a whole that is greater than the sum of its parts. The Global 200 is the list of ecoregions identified by WWF as priorities for conservation, Terrestrial ecoregions are land ecoregions, as distinct from freshwater and marine ecoregions. In this context, terrestrial is used to mean of land, WWF ecologists currently divide the land surface of the Earth into 8 major ecozones containing 867 smaller terrestrial ecoregions. The WWF effort is a synthesis of previous efforts to define. Many consider this classification to be decisive, and some propose these as stable borders for bioregional democracy initiatives. The eight terrestrial ecozones follow the major floral and faunal boundaries, identified by botanists and zoologists, ecozone boundaries generally follow continental boundaries, or major barriers to plant and animal distribution, like the Himalayas and the Sahara
11.
North America
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North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It can also be considered a subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea. North America covers an area of about 24,709,000 square kilometers, about 16. 5% of the land area. North America is the third largest continent by area, following Asia and Africa, and the fourth by population after Asia, Africa, and Europe. In 2013, its population was estimated at nearly 565 million people in 23 independent states, or about 7. 5% of the worlds population, North America was reached by its first human populations during the last glacial period, via crossing the Bering land bridge. The so-called Paleo-Indian period is taken to have lasted until about 10,000 years ago, the Classic stage spans roughly the 6th to 13th centuries. The Pre-Columbian era ended with the migrations and the arrival of European settlers during the Age of Discovery. Present-day cultural and ethnic patterns reflect different kind of interactions between European colonists, indigenous peoples, African slaves and their descendants, European influences are strongest in the northern parts of the continent while indigenous and African influences are relatively stronger in the south. Because of the history of colonialism, most North Americans speak English, Spanish or French, the Americas are usually accepted as having been named after the Italian explorer Amerigo Vespucci by the German cartographers Martin Waldseemüller and Matthias Ringmann. Vespucci, who explored South America between 1497 and 1502, was the first European to suggest that the Americas were not the East Indies, but a different landmass previously unknown by Europeans. In 1507, Waldseemüller produced a map, in which he placed the word America on the continent of South America. He explained the rationale for the name in the accompanying book Cosmographiae Introductio, for Waldseemüller, no one should object to the naming of the land after its discoverer. He used the Latinized version of Vespuccis name, but in its feminine form America, following the examples of Europa, Asia and Africa. Later, other mapmakers extended the name America to the continent, In 1538. Some argue that the convention is to use the surname for naming discoveries except in the case of royalty, a minutely explored belief that has been advanced is that America was named for a Spanish sailor bearing the ancient Visigothic name of Amairick. Another is that the name is rooted in a Native American language, the term North America maintains various definitions in accordance with location and context. In Canadian English, North America may be used to refer to the United States, alternatively, usage sometimes includes Greenland and Mexico, as well as offshore islands
12.
Sierra Nevada (U.S.)
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The Sierra Nevada is a mountain range in the Western United States, between the Central Valley of California and the Basin and Range Province. The vast majority of the lies in the state of California. The Sierra runs 400 miles north-to-south, and is approximately 70 miles across east-to-west, the Sierra is home to three national parks, twenty wilderness areas, and two national monuments. These areas include Yosemite, Sequoia, and Kings Canyon National Parks, the character of the range is shaped by its geology and ecology. More than one hundred years ago during the Nevadan orogeny. The range started to uplift four M. A. ago, the uplift caused a wide range of elevations and climates in the Sierra Nevada, which are reflected by the presence of five life zones. Uplift continues due to faulting caused by forces, creating spectacular fault block escarpments along the eastern edge of the southern Sierra. The Sierra Nevada has a significant history, the California Gold Rush occurred in the western foothills from 1848 through 1855. Due to inaccessibility, the range was not fully explored until 1912, the Sierra Nevada lies in Central and Eastern California, with a very small but historically important spur extending into Nevada. West-to-east, the Sierra Nevadas elevation increases gradually from 1,000 feet in the Central Valley to an height of about 10,500 feet at its crest only 50–75 miles to the east. The east slope forms the steep Sierra Escarpment, unlike its surroundings, the range receives a substantial amount of snowfall and precipitation due to orographic lift. The Sierra Nevada stretches from the Susan River and Fredonyer Pass in the north to Tehachapi Pass in the south and it is bounded on the west by Californias Central Valley and on the east by the Basin and Range Province. The geographical boundary between the Sierra and the Cascades is virtually indistinguishable, with the Fredonyer Pass designation being traditional, physiographically, the Sierra is a section of the Cascade-Sierra Mountains province, which in turn is part of the larger Pacific Mountain System physiographic division. The range is drained on its western slope by the Central Valley watershed, the northern third of the western Sierra is part of the Sacramento River watershed, and the middle third is drained by the San Joaquin River. The eastern slope watershed of the Sierra is much narrower, its rivers flow out into the endorheic Great Basin of eastern California and western Nevada. Although none of the eastern rivers reach the sea, many of the streams from Mono Lake southwards are diverted into the Los Angeles Aqueduct which provides water to Southern California, the height of the mountains in the Sierra Nevada increases gradually from north to south. Between Fredonyer Pass and Lake Tahoe, the range from 5,000 feet to more than 9,000 feet. The crest near Lake Tahoe is roughly 9,000 feet high, farther south, the highest peak in Yosemite National Park is Mount Lyell
