The Celsius scale known as the centigrade scale, is a temperature scale used by the International System of Units. As an SI derived unit, it is used by all countries except the United States, the Bahamas, the Cayman Islands and Liberia, it is named after the Swedish astronomer Anders Celsius. The degree Celsius can refer to a specific temperature on the Celsius scale or a unit to indicate a difference between two temperatures or an uncertainty. Before being renamed to honor Anders Celsius in 1948, the unit was called centigrade, from the Latin centum, which means 100, gradus, which means steps. From 1743, the Celsius scale is based on 0 °C for the freezing point of water and 100 °C for the boiling point of water at 1 atm pressure. Prior to 1743, the scale was based on the boiling and melting points of water, but the values were reversed; the 1743 scale reversal was proposed by Jean-Pierre Christin. By international agreement, since 1954 the unit degree Celsius and the Celsius scale are defined by absolute zero and the triple point of Vienna Standard Mean Ocean Water, a specially purified water.
This definition precisely relates the Celsius scale to the Kelvin scale, which defines the SI base unit of thermodynamic temperature with symbol K. Absolute zero, the lowest temperature possible, is defined as being 0 K and −273.15 °C. The temperature of the triple point of water is defined as 273.16 K. This means that a temperature difference of one degree Celsius and that of one kelvin are the same. On 20 May 2019, the kelvin, along with it the degree Celsius, will be redefined so that its value will be determined by definition of the Boltzmann constant. In 1742, Swedish astronomer Anders Celsius created a temperature scale, the reverse of the scale now known as "Celsius": 0 represented the boiling point of water, while 100 represented the freezing point of water. In his paper Observations of two persistent degrees on a thermometer, he recounted his experiments showing that the melting point of ice is unaffected by pressure, he determined with remarkable precision how the boiling point of water varied as a function of atmospheric pressure.
He proposed that the zero point of his temperature scale, being the boiling point, would be calibrated at the mean barometric pressure at mean sea level. This pressure is known as one standard atmosphere; the BIPM's 10th General Conference on Weights and Measures defined one standard atmosphere to equal 1,013,250 dynes per square centimetre. In 1743, the Lyonnais physicist Jean-Pierre Christin, permanent secretary of the Académie des sciences, belles-lettres et arts de LyonAcadémie des sciences, belles-lettres et arts de Lyon, working independently of Celsius, developed a scale where zero represented the freezing point of water and 100 represented the boiling point of water. On 19 May 1743 he published the design of a mercury thermometer, the "Thermometer of Lyon" built by the craftsman Pierre Casati that used this scale. In 1744, coincident with the death of Anders Celsius, the Swedish botanist Carl Linnaeus reversed Celsius's scale, his custom-made "linnaeus-thermometer", for use in his greenhouses, was made by Daniel Ekström, Sweden's leading maker of scientific instruments at the time, whose workshop was located in the basement of the Stockholm observatory.
As happened in this age before modern communications, numerous physicists and instrument makers are credited with having independently developed this same scale. The first known Swedish document reporting temperatures in this modern "forward" Celsius scale is the paper Hortus Upsaliensis dated 16 December 1745 that Linnaeus wrote to a student of his, Samuel Nauclér. In it, Linnaeus recounted the temperatures inside the orangery at the University of Uppsala Botanical Garden:...since the caldarium by the angle of the windows from the rays of the sun, obtains such heat that the thermometer reaches 30 degrees, although the keen gardener takes care not to let it rise to more than 20 to 25 degrees, in winter not under 15 degrees... Since the 19th century, the scientific and thermometry communities worldwide have used the phrase "centigrade scale". Temperatures on the centigrade scale were reported as degrees or, when greater specificity was desired, as degrees centigrade; because the term centigrade was the Spanish and French language name for a unit of angular measurement and had a similar connotation in other languages, the term centesimal degree was used when precise, unambiguous language was required by international standards bodies such as the BIPM.
More properly, what was defined as "centigrade" would now be "hectograde". To eliminate any confusion, the 9th CGPM and the CIPM formally adopted "degree Celsius" in 1948, formally keeping the recognized degree symbol, rather than adopting the gradian/centesimal degree symbol. For scientific use, "Celsius" is the term used, with "centigrade" remaining in common but decreasing use in informal contexts in English-speaking countries, it was not until February 1985 that the weather forecasts issued by
Humidity is the amount of water vapour present in air. Water vapour, the gaseous state of water, is invisible to the human eye. Humidity indicates the likelihood for dew, or fog to be present; the amount of water vapour needed to achieve saturation increases as the temperature increases. As the temperature of a parcel of air decreases it will reach the saturation point without adding or losing water mass; the amount of water vapour contained within a parcel of air can vary significantly. For example, a parcel of air near saturation may contain 28 grams of water per cubic metre of air at 30 °C, but only 8 grams of water per cubic metre of air at 8 °C. Three primary measurements of humidity are employed: absolute and specific. Absolute humidity describes the water content of air and is expressed in either grams per cubic metre or grams per kilogram. Relative humidity, expressed as a percentage, indicates a present state of absolute humidity relative to a maximum humidity given the same temperature.
Specific humidity is the ratio of water vapor mass to total moist air parcel mass. Humidity plays an important role for surface life. For animal life dependent on perspiration to regulate internal body temperature, high humidity impairs heat exchange efficiency by reducing the rate of moisture evaporation from skin surfaces; this effect can be calculated using a heat index table known as a humidex. Absolute humidity is the total mass of water vapor present in mass of air, it does not take temperature into consideration. Absolute humidity in the atmosphere ranges from near zero to 30 grams per cubic metre when the air is saturated at 30 °C. Absolute humidity is the mass of the water vapor, divided by the volume of the air and water vapor mixture, which can be expressed as: A H = m H 2 O V n e t; the absolute humidity changes as air pressure changes, if the volume is not fixed. This makes it unsuitable for chemical engineering calculations, e.g. in drying, where temperature can vary considerably.
As a result, absolute humidity in chemical engineering may refer to mass of water vapor per unit mass of dry air known as the humidity ratio or mass mixing ratio, better suited for heat and mass balance calculations. Mass of water per unit volume as in the equation above is defined as volumetric humidity; because of the potential confusion, British Standard BS 1339 suggests avoiding the term "absolute humidity". Units should always be checked. Many humidity charts are given in g/kg or kg/kg; the field concerned with the study of physical and thermodynamic properties of gas–vapor mixtures is named psychrometrics. The relative humidity of an air-water mixture is defined as the ratio of the partial pressure of water vapor in the mixture to the equilibrium vapor pressure of water over a flat surface of pure water at a given temperature: ϕ = p H 2 O p H 2 O ∗ Relative humidity is expressed as a percentage. Relative humidity is an important metric used in weather forecasts and reports, as it is an indicator of the likelihood of precipitation, dew, or fog.
In hot summer weather, a rise in relative humidity increases the apparent temperature to humans by hindering the evaporation of perspiration from the skin. For example, according to the Heat Index, a relative humidity of 75% at air temperature of 80.0 °F would feel like 83.6 °F ±1.3 °F. Specific humidity is the ratio of the mass of water vapor to the total mass of the moist air parcel. Specific humidity is equal to the mixing ratio, defined as the ratio of the mass of water vapor in an air parcel to the mass of dry air for the same parcel; as temperature decreases, the amount of water vapor needed to reach saturation decreases. As the temperature of a parcel of air becomes lower it will reach the point of saturation without adding or losing water mass. A device used to measure humidity is called a hygrometer. A humidistat is a humidity-triggered switch used to control a dehumidifier. There are various devices used to regulate humidity. Calibration standards for the most accurate measurement include the gravimetric hygrometer, chilled mirror hygrometer, electrolytic hygrometer.
The gravimetric method, while the most accurate, is cumbersome. For fast and accurate measurement the chilled mirror method is effective. For process on-line measurements, the most used sensors nowadays are based on capacitance measurements to measure relative humidity with internal conversions to d
A census is the procedure of systematically acquiring and recording information about the members of a given population. The term is used in connection with national population and housing censuses; the United Nations defines the essential features of population and housing censuses as "individual enumeration, universality within a defined territory and defined periodicity", recommends that population censuses be taken at least every 10 years. United Nations recommendations cover census topics to be collected, official definitions and other useful information to co-ordinate international practice; the word is of Latin origin: during the Roman Republic, the census was a list that kept track of all adult males fit for military service. The modern census is essential to international comparisons of any kind of statistics, censuses collect data on many attributes of a population, not just how many people there are. Censuses began as the only method of collecting national demographic data, are now part of a larger system of different surveys.
Although population estimates remain an important function of a census, including the geographic distribution of the population, statistics can be produced about combinations of attributes e.g. education by age and sex in different regions. Current administrative data systems allow for other approaches to enumeration with the same level of detail but raise concerns about privacy and the possibility of biasing estimates. A census can be contrasted with sampling in which information is obtained only from a subset of a population. Modern census data are used for research, business marketing, planning, as a baseline for designing sample surveys by providing a sampling frame such as an address register. Census counts are necessary to adjust samples to be representative of a population by weighting them as is common in opinion polling. Stratification requires knowledge of the relative sizes of different population strata which can be derived from census enumerations. In some countries, the census provides the official counts used to apportion the number of elected representatives to regions.
In many cases, a chosen random sample can provide more accurate information than attempts to get a population census. A census is construed as the opposite of a sample as its intent is to count everyone in a population rather than a fraction. However, population censuses rely on a sampling frame to count the population; this is the only way to be sure that everyone has been included as otherwise those not responding would not be followed up on and individuals could be missed. The fundamental premise of a census is that the population is not known and a new estimate is to be made by the analysis of primary data; the use of a sampling frame is counterintuitive as it suggests that the population size is known. However, a census is used to collect attribute data on the individuals in the nation; this process of sampling marks the difference between historical census, a house to house process or the product of an imperial decree, the modern statistical project. The sampling frame used by census is always an address register.
Thus it is not known how many people there are in each household. Depending on the mode of enumeration, a form is sent to the householder, an enumerator calls, or administrative records for the dwelling are accessed; as a preliminary to the dispatch of forms, census workers will check any address problems on the ground. While it may seem straightforward to use the postal service file for this purpose, this can be out of date and some dwellings may contain a number of independent households. A particular problem is what are termed'communal establishments' which category includes student residences, religious orders, homes for the elderly, people in prisons etc; as these are not enumerated by a single householder, they are treated differently and visited by special teams of census workers to ensure they are classified appropriately. Individuals are counted within households and information is collected about the household structure and the housing. For this reason international documents refer to censuses of housing.
The census response is made by a household, indicating details of individuals resident there. An important aspect of census enumerations is determining which individuals can be counted from which cannot be counted. Broadly, three definitions can be used: de facto residence; this is important to consider individuals who have temporary addresses. Every person should be identified uniquely as resident in one place but where they happen to be on Census Day, their de facto residence, may not be the best place to count them. Where an individual uses services may be more useful and this is at their usual, or de jure, residence. An individual may be represented at a permanent address a family home for students or long term migrants, it is necessary to have a precise definition of residence to decide whether visitors to a country should be included in the population count. This is becoming more important as students travel abroad for education for a period of several years. Other groups causing problems of enumeration are new born babies, people away on holiday, people moving home around census day, people without a fixed address.
People having second homes because of working in another part of the country or retaining a holiday cottage are dif
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
United States Census Bureau
The United States Census Bureau is a principal agency of the U. S. Federal Statistical System, responsible for producing data about the American people and economy; the Census Bureau is part of the U. S. Department of Commerce and its director is appointed by the President of the United States; the Census Bureau's primary mission is conducting the U. S. Census every ten years, which allocates the seats of the U. S. House of Representatives to the states based on their population; the Bureau's various censuses and surveys help allocate over $400 billion in federal funds every year and it helps states, local communities, businesses make informed decisions. The information provided by the census informs decisions on where to build and maintain schools, transportation infrastructure, police and fire departments. In addition to the decennial census, the Census Bureau continually conducts dozens of other censuses and surveys, including the American Community Survey, the U. S. Economic Census, the Current Population Survey.
Furthermore and foreign trade indicators released by the federal government contain data produced by the Census Bureau. Article One of the United States Constitution directs the population be enumerated at least once every ten years and the resulting counts used to set the number of members from each state in the House of Representatives and, by extension, in the Electoral College; the Census Bureau now conducts a full population count every 10 years in years ending with a zero and uses the term "decennial" to describe the operation. Between censuses, the Census Bureau makes population projections. In addition, Census data directly affects how more than $400 billion per year in federal and state funding is allocated to communities for neighborhood improvements, public health, education and more; the Census Bureau is mandated with fulfilling these obligations: the collecting of statistics about the nation, its people, economy. The Census Bureau's legal authority is codified in Title 13 of the United States Code.
The Census Bureau conducts surveys on behalf of various federal government and local government agencies on topics such as employment, health, consumer expenditures, housing. Within the bureau, these are known as "demographic surveys" and are conducted perpetually between and during decennial population counts; the Census Bureau conducts economic surveys of manufacturing, retail and other establishments and of domestic governments. Between 1790 and 1840, the census was taken by marshals of the judicial districts; the Census Act of 1840 established a central office. Several acts followed that revised and authorized new censuses at the 10-year intervals. In 1902, the temporary Census Office was moved under the Department of Interior, in 1903 it was renamed the Census Bureau under the new Department of Commerce and Labor; the department was intended to consolidate overlapping statistical agencies, but Census Bureau officials were hindered by their subordinate role in the department. An act in 1920 changed the date and authorized manufacturing censuses every two years and agriculture censuses every 10 years.
In 1929, a bill was passed mandating the House of Representatives be reapportioned based on the results of the 1930 Census. In 1954, various acts were codified into Title 13 of the US Code. By law, the Census Bureau must count everyone and submit state population totals to the U. S. President by December 31 of any year ending in a zero. States within the Union receive the results in the spring of the following year; the United States Census Bureau defines four statistical regions, with nine divisions. The Census Bureau regions are "widely used...for data collection and analysis". The Census Bureau definition is pervasive. Regional divisions used by the United States Census Bureau: Region 1: Northeast Division 1: New England Division 2: Mid-Atlantic Region 2: Midwest Division 3: East North Central Division 4: West North Central Region 3: South Division 5: South Atlantic Division 6: East South Central Division 7: West South Central Region 4: West Division 8: Mountain Division 9: Pacific Many federal, state and tribal governments use census data to: Decide the location of new housing and public facilities, Examine the demographic characteristics of communities and the US, Plan transportation systems and roadways, Determine quotas and creation of police and fire precincts, Create localized areas for elections, utilities, etc.
Gathers population information every 10 years The United States Census Bureau is committed to confidentiality, guarantees non-disclosure of any addresses or personal information related to individuals or establishments. Title 13 of the U. S. Code establishes penalties for the disclosure of this information. All Census employees must sign an affidavit of non-disclosure prior to employment; the Bureau cannot share responses, addresses or personal information with anyone including United States or foreign government
George and Neva Barbee House
The George and Neva Barbee House known as the Dr. G. S. Barbee House, is a historic home located at Zebulon, Wake County, North Carolina, a town near Raleigh, NC. Constructed in 1914, the two-story, brick American Foursquare house was designed in the American Craftsman / Bungalow style, it features a hipped roof with overhanging eaves, a porte cochere, a sheltered wraparound porch, a nearly solid brick porch balustrade. It was listed on the National Register of Historic Places in 2007. List of Registered Historic Places in North Carolina
Pamlico Sound in North Carolina in the US is the largest lagoon along the North American East Coast, extending 80 mi long and 15 to 20 miles wide. It is part of a large, interconnected network of lagoon estuaries that includes Albemarle Sound, Currituck Sound, Croatan Sound, Pamlico Sound, Bogue Sound, Core Sound, Roanoke Sound. Together, these sounds, known as the Albemarle-Pamlico sound system, comprise the second largest estuary in the United States, covering over 3,000 sq. mi. of open water. The Pamlico Sound is separated from the Atlantic Ocean by the Outer Banks, a row of low, sandy barrier islands that include Cape Hatteras National Seashore, Cape Lookout National Seashore, Pea Island National Wildlife Refuge; the Albemarle-Pamlico Sound is one of nineteen great waters recognized by the America's Great Waters Coalition. Pamlico Sound is connected to the north with Albemarle Sound through passages provided by the Roanoke Sound and Croatan Sound. Core Sound is located at the Pamlico's narrow southern end.
It is fed by the Neuse and Pamlico rivers from the west, from the east by Oregon Inlet, Hatteras Inlet, Ocracoke Inlet, which provide passage to the Atlantic Ocean. The salinity of the sound averages 20 ppt, compared to an average coastal salinity of 35 ppt in the Atlantic and 3 ppt in the Currituck Sound, located north of the Albemarle Sound; the sound and its ocean inlets are noted for wide expanses of shallow water and occasional shoaling, making the area hazardous for larger vessels. While the deepest hole of the estuary can be found in the Pamlico Sound, depths range from 5 to 6 feet. In addition, the shallow waters are susceptible to wind and barometric pressure-driven tidal fluctuations; this effect is amplified on the tributary rivers, where water levels can change by as much as two feet in three hours when winds are aligned with the rivers' axes and are blowing strongly. In March 1524, Italian Explorer Giovanni da Verrazzano mistook the sound for the Pacific Ocean because of its wide expanse and separation from the Atlantic Ocean by the Outer Banks barrier islands.
The sound was named for the Pamlico Native American tribe that lived along the sound's mainland banks and who were referred to as the Pamouik by the Raleigh expeditions. Three locations of Pamlico Sound in the Outer Banks between Cape Hatteras and Cape Fear were once under serious consideration by the United States Atomic Energy Commission as an atomic bomb test site during the late 1940s and early 1950s. Portions of Pamlico Sound are used as a training range for Camp Lejeune. In 1987, Congress declared the Albemarle-Pamlico Sound an "estuary of national significance." For vacationers to the Outer Banks, the Pamlico Sound is a "watersports playground" providing opportunities for fishing and crabbing, kayaking, windsurfing, parasailing and more. In 2012, the economic impact of tourism to the Albemarle-Pamlico Sound area exceeded $1.3 billion. The sound supports local commercial fishing, shrimping and oystering. 90% of North Carolina's commercial fishing catches are attributed to the Pamlico Sound, generating $100 million per year.
Along the coastal areas are numerous waterfowl nesting sites, including Pea Island National Wildlife Refuge on the Outer Banks, Swanquarter National Wildlife Refuge on the mainland. Dolphins and sea turtles are abundant, with occasional visits by seals such as harp seal in early January and February. Many other cetaceans including rare species such as fin whales, Cuvier's beaked whales, orcas are present off Outer Banks and Cape Hatteras. Whales such as Atlantic gray, North Atlantic right, North Atlantic humpback were common. Endangered species such as leatherback turtles, great white sharks, basking sharks are known to visit the sound as well; the sound sports a variety of fish populations including red drum, speckled trout, striped bass, spot, pompano and bluefish. In addition, shellfish populations including blue crab, shrimp and clams are healthy. U. S. Geological Survey Geographic Names Information System: Pamlico Sound Pamlico Sound Boating