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Heat Index
The heat index (HI) is an index that combines air temperature and relative humidity, in shaded areas, to posit a human-perceived equivalent temperature, as how hot it would feel if the humidity were some other value in the shade. The result is also known as the "felt air temperature", "apparent temperature", "real feel" or "feels like". For example, when the temperature is with 70% relative humidity, the heat index is . The humidity where the heat index feels like itself is typically left unstated. The heat index example in this case, 41°C, feels like 41°C only when the humidity is 21%. The human body normally cools itself by perspiration, or sweating. Heat is removed from the body by evaporation of that sweat. However, high relative humidity reduces the evaporation rate. This results in a lower rate of heat removal from the body, hence the sensation of being overheated. This effect is subjective, with different individuals perceiving heat differently for various reasons (such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperature
Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have relied on various reference points and thermometric substances for definition. The most common scales are the Celsius scale with the unit symbol °C (formerly called ''centigrade''), the Fahrenheit scale (°F), and the Kelvin scale (K), the latter being used predominantly for scientific purposes. The kelvin is one of the seven base units in the International System of Units (SI). Absolute zero, i.e., zero kelvin or −273.15 °C, is the lowest point in the thermodynamic temperature scale. Experimentally, it can be approached very closely but not actually reached, as recognized in the third law of thermodynamics. It would be impossible to extract energy as heat from a body at that temperature. Temperature is important in all fields of natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Atmospheric Pressure
The standard atmosphere (symbol: atm) is a unit of pressure defined as Pa. It is sometimes used as a ''reference pressure'' or ''standard pressure''. It is approximately equal to Earth's average atmospheric pressure at sea level. History The standard atmosphere was originally defined as the pressure exerted by 760 mm of mercury at and standard gravity (''g''n = ). It was used as a reference condition for physical and chemical properties, and was implicit in the definition of the Celsius temperature scale, which defined as the boiling point of water at this pressure. In 1954, the 10th General Conference on Weights and Measures (CGPM) adopted ''standard atmosphere'' for general use and affirmed its definition of being precisely equal to dynes per square centimetre (). This defined both temperature and pressure independent of the properties of particular substance. In addition, the CGPM noted that there had been some misapprehension that it "led some physicists to believe th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Index Graph
In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is also often used to refer to the thermal energy contained in a system as a component of its internal energy and that is reflected in the temperature of the system. For both uses of the term, heat is a form of energy. An example of formal vs. informal usage may be obtained from the right-hand photo, in which the metal bar is "conducting heat" from its hot end to its cold end, but if the metal bar is considered a thermodynamic system, then the energy flowing within the metal bar is called internal energy, not heat. The hot metal bar is also transferring heat to its surroundings, a correct statement for both the strict and loose meanings of ''heat''. Another example of informal usage is the term '' heat content'', used despite the fact that ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Index Plot
In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is also often used to refer to the thermal energy contained in a system as a component of its internal energy and that is reflected in the temperature of the system. For both uses of the term, heat is a form of energy. An example of formal vs. informal usage may be obtained from the right-hand photo, in which the metal bar is "conducting heat" from its hot end to its cold end, but if the metal bar is considered a thermodynamic system, then the energy flowing within the metal bar is called internal energy, not heat. The hot metal bar is also transferring heat to its surroundings, a correct statement for both the strict and loose meanings of ''heat''. Another example of informal usage is the term '' heat content'', used despite the fact that p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Oceanic And Atmospheric Administration
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditions, charts the seas, conducts deep sea exploration, and manages fishing and protection of marine mammals and endangered species in the U.S. exclusive economic zone. Purpose and function NOAA's specific roles include: * ''Supplying Environmental Information Products''. NOAA supplies to its customers and partners information pertaining to the state of the oceans and the atmosphere, such as weather warnings and forecasts via the National Weather Service. NOAA's information services extend as well to climate, ecosystems, and commerce. * ''Providing Environmental Stewardship Services''. NOAA is a steward of U.S. coastal and marine environments. In coordination with federal, state, local, tribal and international authorities, NOAA manages the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wet Bulb Globe Temperature
The wet-bulb globe temperature (WBGT) is a type of apparent temperature used to estimate the effect of temperature, humidity, wind speed (wind chill), and visible and infrared radiation (usually sunlight) on humans. It is used by industrial hygienists, athletes, sporting events and the military to determine appropriate exposure levels to high temperatures. It is derived from the following formula: :\mathrm = 0.7T_\mathrm + 0.2T_\mathrm + 0.1T_\mathrm where * ''T''w = Natural wet-bulb temperature (combined with dry-bulb temperature indicates humidity) * ''T''g = Globe thermometer temperature (measured with a globe thermometer, also known as a black globe thermometer) * ''T''d = Dry-bulb temperature (actual air temperature) * Temperatures may be in either Celsius or Fahrenheit Indoors, or when solar radiation is negligible, the following formula is often used: :\mathrm = 0.7T_\mathrm + 0.3T_\mathrm Uses The American Conference of Governmental Industrial Hygienists publish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wet-bulb Temperature
The wet-bulb temperature (WBT) is the temperature read by a thermometer covered in water-soaked (water at ambient temperature) cloth (a wet-bulb thermometer) over which air is passed. At 100% relative humidity, the wet-bulb temperature is equal to the air temperature (dry-bulb temperature); at lower humidity the wet-bulb temperature is lower than dry-bulb temperature because of evaporative cooling. The wet-bulb temperature is defined as the temperature of a parcel of air cooled to saturation (100% relative humidity) by the evaporation of water into it, with the latent heat supplied by the parcel. A wet-bulb thermometer indicates a temperature close to the true (thermodynamic) wet-bulb temperature. The wet-bulb temperature is the lowest temperature that can be reached under current ambient conditions by the evaporation of water only. Even heat-adapted people cannot carry out normal outdoor activities past a wet-bulb temperature of , equivalent to a heat index of . The theoretic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saudi Arabia
Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the fifth-largest country in Asia, the second-largest in the Arab world, and the largest in Western Asia and the Middle East. It is bordered by the Red Sea to the west; Jordan, Iraq, and Kuwait to the north; the Persian Gulf, Qatar and the United Arab Emirates to the east; Oman to the southeast; and Yemen to the south. Bahrain is an island country off the east coast. The Gulf of Aqaba in the northwest separates Saudi Arabia from Egypt. Saudi Arabia is the only country with a coastline along both the Red Sea and the Persian Gulf, and most of its terrain consists of arid desert, lowland, steppe, and mountains. Its capital and largest city is Riyadh. The country is home to Mecca and Medina, the two holiest cities in Islam. Pre-Islamic Arabia, the territory that constitutes modern-day Saudi Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dhahran
Dhahran ( ar, الظهران, ''Al-Dhahran'') is a city located in the Eastern Province, Saudi Arabia. With a total population of 240,742 as of 2021, it is a major administrative center for the Saudi oil industry. Together with the nearby cities of Dammam and Khobar, Dhahran forms part of the Dammam Metropolitan Area, which is commonly known as greater Dammam and has an estimated population of 4,140,000 as of 2012. Large oil reserves were first identified in the Dhahran area in 1931, and in 1935, American company Standard Oil drilled the first commercially viable oil well. Standard Oil later established a subsidiary in Saudi Arabia called the Arabian American Oil Company (ARAMCO), now owned by the Saudi government and known as Saudi Aramco. Dhahran has been the home of Saudi Aramco's headquarters for 80 years and is its first and largest gated compound with more than 50,000 residents. Employees and dependents of Aramco, known as Aramcons, have a tendency to use Dhahran to s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AccuWeather
AccuWeather Inc. is an American media company that provides commercial weather forecasting services worldwide. AccuWeather was founded in 1962 by Joel N. Myers, then a Pennsylvania State University graduate student working on a master's degree in meteorology. His first customer was a natural gas, gas company in Pennsylvania. While running his company, Myers also worked as a member of Penn State's meteorology faculty. The company adopted the name "AccuWeather" in 1971. AccuWeather is headquartered in Ferguson Township, Centre County, Pennsylvania, Ferguson Township, just outside of State College, Pennsylvania, State College, Pennsylvania, with offices at 80 Pine Street in Financial_District,_Manhattan, Manhattan's Financial District in addition to Wichita, Kansas, Wichita, Kansas, and Oklahoma City, Oklahoma. Internationally, AccuWeather has offices in Montreal, Tokyo, Beijing, Seoul, and Mumbai. Company profile AccuWeather provides weather forecasts and warnings and additional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wet-bulb Globe Temperature
The wet-bulb globe temperature (WBGT) is a type of apparent temperature used to estimate the effect of temperature, humidity, wind speed ( wind chill), and visible and infrared radiation (usually sunlight) on humans. It is used by industrial hygienists, athletes, sporting events and the military to determine appropriate exposure levels to high temperatures. It is derived from the following formula: :\mathrm = 0.7T_\mathrm + 0.2T_\mathrm + 0.1T_\mathrm where * ''T''w = Natural wet-bulb temperature (combined with dry-bulb temperature indicates humidity) * ''T''g = Globe thermometer temperature (measured with a globe thermometer, also known as a black globe thermometer) * ''T''d = Dry-bulb temperature (actual air temperature) * Temperatures may be in either Celsius or Fahrenheit Indoors, or when solar radiation is negligible, the following formula is often used: :\mathrm = 0.7T_\mathrm + 0.3T_\mathrm Uses The American Conference of Governmental Industrial Hygienists publishe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parameterization
In mathematics, and more specifically in geometry, parametrization (or parameterization; also parameterisation, parametrisation) is the process of finding parametric equations of a curve, a surface, or, more generally, a manifold or a variety, defined by an implicit equation. The inverse process is called implicitization. "To parameterize" by itself means "to express in terms of parameters". Parametrization is a mathematical process consisting of expressing the state of a system, process or model as a function of some independent quantities called parameters. The state of the system is generally determined by a finite set of coordinates, and the parametrization thus consists of one function of several real variables for each coordinate. The number of parameters is the number of degrees of freedom of the system. For example, the position of a point that moves on a curve in three-dimensional space is determined by the time needed to reach the point when starting from a fixed orig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
