Population density is a measurement of population per unit area or unit volume. It is applied to living organisms, most of the time to humans, it is a key geographical term. In simple terms population density refers to the number of people living in an area per kilometer square. Population density is population divided by total land water volume, as appropriate. Low densities may lead to further reduced fertility; this is called the Allee effect after the scientist. Examples of the causes in low population densities include: Increased problems with locating sexual mates Increased inbreeding For humans, population density is the number of people per unit of area quoted per square kilometer or square mile; this may be calculated for a county, country, another territory or the entire world. The world's population is around 7,500,000,000 and Earth's total area is 510,000,000 square kilometers. Therefore, the worldwide human population density is around 7,500,000,000 ÷ 510,000,000 = 14.7 per km2. If only the Earth's land area of 150,000,000 km2 is taken into account human population density is 50 per km2.
This includes all continental and island land area, including Antarctica. If Antarctica is excluded population density rises to over 55 people per km2. However, over half of the Earth's land mass consists of areas inhospitable to human habitation, such as deserts and high mountains, population tends to cluster around seaports and fresh-water sources. Thus, this number by itself does not give any helpful measurement of human population density. Several of the most densely populated territories in the world are city-states and dependencies; these territories have a small area and a high urbanization level, with an economically specialized city population drawing on rural resources outside the area, illustrating the difference between high population density and overpopulation The potential to maintain the agricultural aspects of deserts is limited as there is not enough precipitation to support a sustainable land. The population in these areas are low. Therefore, cities in the Middle East, such as Dubai, have been increasing in population and infrastructure growth at a fast pace.
Cities with high population densities are, by some, considered to be overpopulated, though this will depend on factors like quality of housing and infrastructure and access to resources. Most of the most densely populated cities are in Southeast Asia, though Cairo and Lagos in Africa fall into this category. City population and area are, however dependent on the definition of "urban area" used: densities are invariably higher for the central city area than when suburban settlements and the intervening rural areas are included, as in the areas of agglomeration or metropolitan area, the latter sometimes including neighboring cities. For instance, Milwaukee has a greater population density when just the inner city is measured, the surrounding suburbs excluded. In comparison, based on a world population of seven billion, the world's inhabitants, as a loose crowd taking up ten square feet per person, would occupy a space a little larger than Delaware's land area; the Gaza Strip has a population density of 5,046 pop/km.
Although arithmetic density is the most common way of measuring population density, several other methods have been developed to provide a more accurate measure of population density over a specific area. Arithmetic density: The total number of people / area of land Physiological density: The total population / area of arable land Agricultural density: The total rural population / area of arable land Residential density: The number of people living in an urban area / area of residential land Urban density: The number of people inhabiting an urban area / total area of urban land Ecological optimum: The density of population that can be supported by the natural resources Demography Human geography Idealized population Optimum population Population genetics Population health Population momentum Population pyramid Rural transport problem Small population size Distance sampling List of population concern organizations List of countries by population density List of cities by population density List of city districts by population density List of English districts by population density List of European cities proper by population density List of United States cities by population density List of islands by population density List of U.
S. states by population density List of Australian suburbs by population density Selected Current and Historic City, Ward & Neighborhood Density Duncan Smith / UCL Centre for Advanced Spatial Analysis. "World Population Density". Exploratory map shows data from the Global Human Settlement Layer produced by the European Commission JRC and the CIESIN Columbia University
1910 United States Census
The Thirteenth United States Census, conducted by the Census Bureau on April 15, 1910, determined the resident population of the United States to be 92,228,496, an increase of 21.0 percent over the 76,212,168 persons enumerated during the 1900 Census. The 1910 Census switched from a portrait page orientation to a landscape orientation; the 1910 census collected the following information: Full documentation for the 1910 census, including census forms and enumerator instructions, is available from the Integrated Public Use Microdata Series. The column titles in the census form are as follows: LOCATION. Street, road, etc. House number. 1. Number of dwelling house in order of visitation. 2. Number of family in order of visitation. 3. NAME of each person whose place of abode on April 15, 1910, was in this family. Enter surname first the given name and middle initial, if any. Include every person living on April 15, 1910. Omit children born since April 15, 1910. RELATION. 4. Relationship of this person to the head of the family.
PERSONAL DESCRIPTION. 5. Sex. 6. Color or race. 7. Age at last birthday. 8. Whether single, widowed, or divorced. 9. Number of years of present marriage. 10. Mother of how many children: Number born. 11. Mother of how many children: Number now living. NATIVITY. Place of birth of each person and parents of each person enumerated. If born in the United States, give the state or territory. If of foreign birth, give the country. 12. Place of birth of this Person. 13. Place of birth of Father of this person. 14. Place of birth of Mother of this person. CITIZENSHIP. 15. Year of immigration to the United States. 16. Whether naturalized or alien. 17. Whether able to speak English. OCCUPATION. 18. Trade or profession of, or particular kind of work done by this person, as spinner, laborer, etc. 19. General nature of industry, business, or establishment in which this person works, as cotton mill, dry goods store, etc. 20. Whether as employer, employee, or work on own account. If an employee— 21. Whether out of work on April 15, 1910.
22. Number of weeks out of work during year 1909. EDUCATION. 23. Whether able to read. 24. Whether able to write. 25. Attended school any time since September 1, 1909. OWNERSHIP OF HOME. 26. Owned or rented. 27. Owned free or mortgaged. 28. Farm or house. 29. Number of farm schedule. 30. Whether a survivor of the Union or Confederate Army or Navy. 31. Whether blind. 32. Whether deaf and dumb. Special Notation In 1912 and 1959, New Mexico, Arizona and Hawaii would become the 47th, 48th, 49th and 50th states admitted to the Union; the 1910 population count for each of these areas was 327,301, 204,354, 64,356 and 191,909 respectively. On this basis, the ranking list above would be modified as follows: First 42 ranked states - positions unchanged New Mexico, Arizona, Hawaii, Wyoming and Alaska; the original census enumeration sheets were microfilmed by the Census Bureau in the 1940s. The microfilmed census is available in rolls from the National Records Administration. Several organizations host images of the microfilmed census online, along which digital indices.
Microdata from the 1910 census are available through the Integrated Public Use Microdata Series. Aggregate data for small areas, together with electronic boundary files, can be downloaded from the National Historical Geographic Information System. 1911 U. S Census Report Contains 1910 Census results Historic US Census data census.gov/population/www/censusdata/PopulationofStatesandCountiesoftheUnitedStates1790-1990.pdf
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
A derecho is a widespread, long-lived, straight-line wind storm, associated with a fast-moving group of severe thunderstorms known as a mesoscale convective system. Derechos can cause hurricane-force winds, heavy rains, flash floods. In many cases, convection-induced winds take on a bow echo form of squall line forming beneath an area of diverging upper tropospheric winds troposphere, in a region of both rich low-level moisture and both warm-air advection. Derechos move in the direction of movement of their associated storms, similar to an outflow boundary, except that the wind remains sustained for a greater period of time, may exceed hurricane-force. A derecho-producing convective system may remain active for many hours and over multiple days. A warm-weather phenomenon, derechos occur in summer during June and August in the Northern Hemisphere, within areas of moderately strong instability and moderately strong vertical wind shear. However, derechos may occur at any time of the year, can occur as at night as during the day.
Various studies since the 1980s have shed light on the physical processes responsible for the production of widespread damaging winds by thunderstorms. In addition, it has become apparent that the most damaging derechos are associated with particular types of mesoscale convective systems that are self-perpetuating. In addition, the term "derecho" sometimes is misapplied to convectively-generated wind events that are not well-organized or long-lasting. For these reasons, a more precise, physically-based definition of "derecho" has been introduced within the meteorological community. Derecho comes from the Spanish word in adjective form for "straight", in contrast with a tornado, a "twisted" wind; the word was first used in the American Meteorological Journal in 1888 by Gustavus Detlef Hinrichs in a paper describing the phenomenon and based on a significant derecho event that crossed Iowa on 31 July 1877. Organized areas of thunderstorm activity reinforce pre-existing frontal zones, can outrun cold fronts.
The resultant mesoscale convective system forms at the point of the strongest divergence of the upper-level flow in the area of greatest low-level inflow and convergence. The convection tends to move east or toward the equator parallel to low-level thickness lines and somewhat to the right of the mean tropospheric flow; when the convection is linear or curved, the MCS is called a squall line, with the strongest winds occurring just behind the leading edge of the significant wind shift and pressure rise. Classic derechos occur with squall lines that contain bow- or spearhead-shaped features as seen by weather radar that are known as bow echoes or spearhead echoes. Squall lines "bow out" due to the formation of a mesoscale high pressure system which forms within the stratiform rain area behind the initial convective line; this high pressure area is formed due to strong descending air currents behind the squall line, could come in the form of a downburst. The size of the bow may vary, the storms associated with the bow may die and redevelop.
During the cool season within the Northern Hemisphere, derechos develop within a pattern of mid-tropospheric southwesterly winds, in an environment of low to moderate atmospheric instability, high values of vertical wind shear within the lowest 5 km of the atmosphere). Warm season derechos in the Northern Hemisphere most form in west to northwesterly flow at mid-levels of the troposphere, with moderate to high levels of thermodynamic instability; as mentioned, derechos favor environments of low-level warm advection and significant low-level moisture. A common definition is a thunderstorm complex that produces a damaging wind swath of at least 400 km, featuring a concentrated area of convectively-induced wind gusts exceeding 30 m/s. According to the National Weather Service criterion, a derecho is classified as a band of storms that have winds of at least 30 m/s along the entire span of the storm front, maintained over a time span of at least six hours; some studies add a requirement that no more than two or three hours separate any two successive wind reports.
A more recent, more physically-based definition of "derecho" proposes that the term be reserved for use with convective systems that not only contain unique radar-observed features such as bow echoes and mesovortices, but for events that produce damage swaths at least 100 km wide and 650 km long. Four types of derechos are recognized: Serial derecho – This type of derecho is associated with a deep low. Single-bow – A large bow echo around or upwards of 400 km long; this type of serial derecho is less common than the multi-bow kind. An example of a single-bow serial derecho is the derecho that occurred in association with the October 2010 North American storm complex. Multi-bow – Multiple bow derechos are embedded in a large squall line around 400 km long. One example of a multi-bow serial derecho is a derecho that occurred during the 1993 Storm of the Century in Florida; because of embedd
1940 United States Census
The Sixteenth United States Census, conducted by the Census Bureau, determined the resident population of the United States to be 132,164,569, an increase of 7.3 percent over the 1930 population of 123,202,624 people. The census date of record was April 1, 1940. A number of new questions were asked including where people were 5 years before, highest educational grade achieved, information about wages; this census introduced sampling techniques. Other innovations included a field test of the census in 1939; this was the first census in which every state had a population greater than 100,000. The 1940 census collected the following information: In addition, a sample of individuals were asked additional questions covering age at first marriage and other topics. Full documentation on the 1940 census, including census forms and a procedural history, is available from the Integrated Public Use Microdata Series. Following completion of the census, the original enumeration sheets were microfilmed; as required by Title 13 of the U.
S. Code, access to identifiable information from census records was restricted for 72 years. Non-personally identifiable information Microdata from the 1940 census is available through the Integrated Public Use Microdata Series. Aggregate data for small areas, together with electronic boundary files, can be downloaded from the National Historical Geographic Information System. On April 2, 2012—72 years after the census was taken—microfilmed images of the 1940 census enumeration sheets were released to the public by the National Archives and Records Administration; the records are indexed only by enumeration district upon initial release. Official 1940 census website 1940 Census Records from the U. S. National Archives and Records Administration 1940 Federal Population Census Videos, training videos for enumerators at the U. S. National Archives Selected Historical Decennial Census Population and Housing Counts from the U. S. Census Bureau Snow, Michael S. "Why the huge interest in the 1940 Census?"
CNN. Monday April 9, 2012. 1941 U. S Census Report Contains 1940 Census results 1940 Census Questions Hosted at CensusFinder.com
Somerset Township, Jackson County, Illinois
Somerset Township is one of sixteen townships in Jackson County, Illinois, USA. As of the 2010 census, its population was 4,205 and it contained 1,886 housing units. According to the 2010 census, the township has a total area of 37.63 square miles, of which 37.13 square miles is land and 0.49 square miles is water. Murphysboro Harrison at 37.796718°N 89.337033°W / 37.796718. Illinois Route 13 Illinois Route 149 Lake Murphysboro State Park Elverado Community Unit School District 196 Murphysboro Community Unit School District 186 Illinois' 12th congressional district State House District 115 State Senate District 58 "Somerset Township, Jackson County, Illinois". Geographic Names Information System. United States Geological Survey. Retrieved 2010-01-17. United States Census Bureau 2007 TIGER/Line Shapefiles United States National Atlas City-Data.com Illinois State Archives
The Tri-State Tornado of Wednesday, March 18, 1925 was the deadliest tornado in United States history. It was the most exceptional tornado during a major outbreak of at least 12 known significant tornadoes, spanning a large portion of the Midwestern and Southern United States; this one tornado alone inflicted 695 fatalities, more than twice as many as the second deadliest, the Great Natchez, Mississippi Tornado of May 7, 1840. The 151 to 235 mi track left by the tornado was the longest recorded in the world as it crossed from southeastern Missouri, through southern Illinois into southwestern Indiana. Although not rated by NOAA, it is recognized by most experts as an F5 tornado, the maximum damage rating issued on the Fujita scale; the tornado was first sighted as a visible and small condensation funnel in the rugged forested hills of Moore Township, Shannon County, Missouri at about 1:00 p.m. The first fatality occurred around 1:01 p.m. north-northwest of Ellington by which time the tornado had grown large.
Several homes and other structures were destroyed north of town. The tornado sped to the northeast, causing $500,000 worth of property damage and the near annihilation of Annapolis, where much of the town was leveled, two people were killed; the tornado struck the mining town of Leadanna, where mining machinery and several structures were destroyed, two other people were killed. In Bollinger County, 32 children were injured when two schools were damaged and multiple homes were destroyed. Deep ground scouring was observed near the town of Sedgewickville as well; the tornado carried sheets of iron as far as 50 mi away. Crossing into Perry County, the tornado displayed a double funnel as it struck the town of Biehle, destroying many homes in and around the town, killing four people. Numerous other homes were leveled near Frohna as well; the town of Cornwall was hit by the tornado. At least 11 people died altogether in Missouri; the tornado crossed the Mississippi River into southern Illinois, debarking trees and scouring the ground in rural areas before hitting the town of Gorham, at 2:30 pm obliterating the entire town, killing 34.
Every structure in Gorham was leveled or swept away, railroad tracks were ripped from the ground. More than half the town's population was injured or killed and seven fatalities occurred at a school. Continuing to the northeast at an average speed of 62 mph, the tornado cut a swath 1 mi wide through Murphysboro flattening a large portion of the town. Entire rows of homes were swept away in some areas. Many other structures were damaged or destroyed throughout the town, including the M&O railroad shop, where 35 people were killed. Schools in the area were devastated as well, with 17 students killed at the Longfellow School, 9 others killed at the Logan School. After the tornado passed, large fires ignited and swept through the rubble, burning many of the trapped survivors alive. In Murphysboro, a total of 234 were killed, the most tornadic deaths in a single city in U. S. history. The tornado struck the nearby town of De Soto, devastated. 69 people were killed there, many homes were swept away. 33 of the deaths were students that were killed in the partial collapse of the De Soto School, the worst tornadic death toll at a single school in U.
S. history. The tornado continued impacted the small village of Bush, killing seven people there. Several homes were leveled, pieces of wood were speared into the town's water tower. Heavy railroad axles were lifted and scattered across the railyard. Further east, the mining town of West Frankfort was devastated by the massive tornado, with 152 fatalities occurring in that area; the tornado struck the northwest side of town, leveling many businesses and sweeping away entire subdivisions. At the Orient Mine, a large multi-ton coal tipple was rolled by the tornado. Extreme damage continued east of town, as a railroad trestle was torn from its supports, 300 ft of railroad track was ripped from the ground and blown away. Several small mining villages in the area were obliterated; the tornado destroyed the small town of Parrish, where 22 people were killed, the town was never rebuilt. Severe damage and several fatalities occurred in the Olga area in Hamilton County west of Dale. Within 40 minutes, 541 lives were lost and 1,423 were injured.
The tornado proceeded to devastate additional rural areas across Hamilton and White counties, claiming 65 more residents before crossing into Indiana. An estimated 613 people died in Illinois, the most tornadic deaths within a state in U. S. history. Crossing the Wabash River into Indiana, the tornado struck and demolished all of Griffin, where most structures were leveled, some were swept away. 26 people were killed there. The tornado devastated rural areas, clipped the town of Owensville, resulting in two fatalities in that town; the tornado roared into Princeton, destroying half the town and killing 45 people. Large sections of neighborhoods in Princeton were leveled, a Heinz factory was badly damaged; the tornado traveled more than 10 mi to the northeast before dissipating at about 4:38 pm around 2.5 mi south-southeast of Petersburg. In Indiana, at least 71 perished. In all, at least 695 people died and 2,027 were injured, the majority in southern Illinois. Three states, 13 counties, more than 19 communities, four of which were effaced (several of these