National Weather Service
The National Weather Service is an agency of the United States federal government, tasked with providing weather forecasts, warnings of hazardous weather, other weather-related products to organizations and the public for the purposes of protection and general information. It is a part of the National Oceanic and Atmospheric Administration branch of the Department of Commerce, is headquartered in Silver Spring, within the Washington metropolitan area; the agency was known as the United States Weather Bureau from 1890 until it adopted its current name in 1970. The NWS performs its primary task through a collection of national and regional centers, 122 local Weather Forecast Offices; as the NWS is an agency of the U. S. federal government, most of its products are in available free of charge. In 1870, the Weather Bureau of the United States was established through a joint resolution of Congress signed by President Ulysses S. Grant with a mission to "provide for taking meteorological observations at the military stations in the interior of the continent and at other points in the States and Territories...and for giving notice on the northern Lakes and on the seacoast by magnetic telegraph and marine signals, of the approach and force of storms."
The agency was placed under the Secretary of War as Congress felt "military discipline would secure the greatest promptness and accuracy in the required observations." Within the Department of War, it was assigned to the U. S. Army Signal Service under Brigadier General Albert J. Myer. General Myer gave the National Weather Service its first name: The Division of Telegrams and Reports for the Benefit of Commerce. Cleveland Abbe – who began developing probabilistic forecasts using daily weather data sent by the Cincinnati Chamber of Commerce and Western Union, which he convinced to back the collection of such information in 1869 – was appointed as the Bureau's first chief meteorologist. In his earlier role as the civilian assistant to the chief of the Signal Service, Abbe urged the Department of War to research weather conditions to provide a scientific basis behind the forecasts. While a debate went on between the Signal Service and Congress over whether the forecasting of weather conditions should be handled by civilian agencies or the Signal Service's existing forecast office, a Congressional committee was formed to oversee the matter, recommending that the office's operations be transferred to the Department of War following a two-year investigation.
The agency first became a civilian enterprise in 1890, when it became part of the Department of Agriculture. Under the oversight of that branch, the Bureau began issuing flood warnings and fire weather forecasts, issued the first daily national surface weather maps; the first Weather Bureau radiosonde was launched in Massachusetts in 1937, which prompted a switch from routine aircraft observation to radiosondes within two years. The Bureau prohibited the word "tornado" from being used in any of its weather products out of concern for inciting panic until 1938, when it began disseminating tornado warnings to emergency management personnel; the Bureau would be moved to the Department of Commerce in 1940. On July 12, 1950, bureau chief Francis W. Reichelderfer lifted the agency's ban on public tornado alerts in a Circular Letter, noting to all first order stations that "Weather Bureau employees should avoid statements that can be interpreted as a negation of the Bureau's willingness or ability to make tornado forecasts", that a "good probability of verification" exist when issuing such forecasts due to the difficulty in predicting tornadic activity.
However it would not be until it faced criticism for continuing to refuse to provide public tornado warnings and preventing the release of the USAF Severe Weather Warning Center's tornado forecasts beyond military personnel that the Bureau issued its first experimental public tornado forecasts in March 1952. In 1957, the Bureau began using radars for short-term forecasting of local storms and hydrological events, using modified versions of those used by Navy aircraft to create the WSR-57, with a network of WSR systems being deployed nationwide through the early 1960s; the Weather Bureau became part of the Environmental Science Services Administration when that agency was formed in August 1966. The Environmental Science Services Administration was renamed the National Oceanic and Atmospheric Administration on October 1, 1970, with the enactment of the National Environmental Policy Act. At this time, the Weather Bureau became the National Weather Service. NEXRAD, a system of Doppler radars deployed to improve the detection and warning time of severe local storms, replaced the WSR-57 and WSR-74 systems between 1988 and 1997.
Bob Glahn has written a comprehensive history of the first hundred years of the National Weather Service. The NWS, through a variety of sub-organizations, issues different forecasts to users, including the general public. Although, throughout history, text forecasts have been the means of product dissemination, the NWS has been using more forecast products of a digital, gridded, im
Hurricane Dennis was an early-forming major hurricane in the Caribbean and Gulf of Mexico during the record-breaking 2005 Atlantic hurricane season. Dennis was the fourth named storm, second hurricane, first major hurricane of the season. Forming in July, the hurricane became the strongest Atlantic hurricane to form before August at the time, a title it held for only six days before being surpassed by Hurricane Emily. Dennis made landfall in Cuba twice as a Category 4 hurricane on the Saffir-Simpson scale and made landfall on the United States' Florida Panhandle as a Category 3 storm, coming less than a year after the devastating Hurricane Ivan. Dennis killed 88 people in total and was responsible for $2.5 billion in damages to the United States, not counting additional damage in the Caribbean. The tropical wave that became Dennis was identified by the National Hurricane Center on June 26, 2005, well inland over Africa, it emerged over the Atlantic Ocean on June 29 and moved to the west. Dry conditions over the Sahara inhibited development, though the wave found more favorable conditions and intensified into a tropical depression on July 4 while nearing the Windward Islands.
The depression soon crossed the island country of Grenada before entering the Caribbean Sea, where favorable environmental factors, such as low wind shear and high sea surface temperatures, fueled intensification. Turning west-northwest, the system achieved tropical storm status on July 5 and hurricane status the following day. Formation of a well-defined eye and central dense overcast signaled Dennis's intensification into a major hurricane on July 7; the hurricane subsequently traversed the Jamaica Channel, bringing deadly floods to both Jamaica and Haiti. The powerful storm soon struck Granma Province, Cuba, as a Category 4 hurricane early on July 8. Weakening due to interaction with land, Dennis regained its strength. Paralleling the southwestern coast of Cuba, Dennis attained its peak winds of 150 mph that day before making a second landfall in the country, this time in Matanzas Province. Interaction with the mountains of Cuba caused significant weakening; the hurricane reached Category 4 strength for the third time on July 10 as it approached Florida, attaining its lowest barometric pressure of 930 mbar.
This ranked Dennis as the strongest hurricane in the Atlantic basin to form before August. Weakening ensued as the hurricane approached the Florida Panhandle, the storm making landfall over Santa Rosa Island on July 10 as a Category 3. Weakening continued as the cyclone moved further inland, the storm lost tropical cyclone status. Dennis' remnant circulation remained, traversing the Mississippi River Valley and Ohio River Valley before dissipating over Ontario on July 18. In Haiti, officials noted that many were not obliging. In Cuba more than 600,000 residents were moved from their homes to government shelters or other locations in anticipation of Dennis. All schools were closed, most flights in the country were suspended or cancelled; the Cayman Islands chapter of the Red Cross opened shelters on July 7 and placed 120 volunteers on standby. Schools and government offices closed for the duration of Dennis's passage. In the United States, the governors of Florida, Alabama and Louisiana all declared states of emergency in their states.
At 6 am CDT on July 9, 2005, all southbound lanes on Interstate 65 from Mobile to Montgomery, were closed. Traffic was redirected. In Alabama residents in all parts of Mobile County, those south of I-10 in Baldwin County, were ordered to evacuate. Similar orders were issued in Mississippi for parts of Jackson and Harrison counties. Military installations such as NAS Pensacola, Whiting Field, Eglin AFB, Hurlburt Field and Tyndall AFB were all evacuated days before the storm. Additionally, Red Cross officials opened 87 shelters across the state which were able to hold about 14,000 evacuees. In Florida, about 50,000 tourists in the Keys were forced to evacuate by July 8; the MacDill Air Force Base in Tampa evacuated its aircraft to McConnell Air Force Base near Wichita, Kansas. 700,000 people in the Florida panhandle were evacuated in the days prior to Dennis, 100,000 of them in Escambia County alone. As a result of the large evacuations, more than 200 truckloads provided about 1.8 million gallons of gasoline.
The Red Cross moved 60 mobile canteens capable of serving 30,000 hot meals each a day to the staging points of Hattiesburg and Jackson. National guardsmen were mobilized, four emergency medical teams, each capable of setting up a small field hospital, were on standby. At Eglin Air Force Base, about 20,000 military personnel were evacuated, at Hurlburt Field, home to Air Force's 16th Special Operations Wing, a mandatory evacuation was ordered for all 15,000 airmen and their families. Heavy rain from the outer bands of Dennis produced widespread flooding and landslides in Haiti; the resulting torrents killed at least 56 people, injured 36 others, left 24 more missing. At least nine of the fatalities occurred. Extensive property damage was incurred with 929 homes destroyed and another 3,058 damaged, leaving 1,500 families homeles
2005 Atlantic hurricane season
The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in recorded history, shattering numerous records. The impact of the season was catastrophic, its storms caused an estimated total of 3,960 deaths and $180.7 billion in damage, making it the second costliest season on record, surpassed only by the 2017 season. Of the storms that made landfall, five of the season's seven major hurricanes—Dennis, Katrina and Wilma—were responsible for the majority of the destruction. Stan was the most destructive storm, not a major hurricane; the Mexican states of Quintana Roo and Yucatán and the U. S. states of Florida and Louisiana were each struck twice by major hurricanes. The most devastating effects of the season were felt on the United States' Gulf Coast, where a 30-foot storm surge from Hurricane Katrina caused severe flooding that destroyed most structures on the Mississippi coastline. Furthermore, Hurricane Stan combined with an extratropical system to cause deadly mudslides across Central America, with Guatemala being hardest-hit.
The 2005 season was the first to observe more tropical storms and cyclones in the Atlantic than in the West Pacific. This event was repeated in the 2010 season; the season began on June 1, 2005, lasted until November 30, although it persisted into January 2006 due to continued storm activity. A record twenty-eight tropical and subtropical storms formed, of which a record fifteen became hurricanes. Of these, a record-tying seven strengthened into major hurricanes, a record-tying five became Category 4 hurricanes and a record four reached Category 5 strength, the highest categorization for hurricanes on the Saffir-Simpson Hurricane Scale. Among these Category 5 storms were hurricanes Katrina and Wilma the second costliest and the most intense Atlantic hurricanes on record; the 2005 season was notable because the annual pre-designated list of storm names was used up and six Greek letter names had to be used. Forecasts of hurricane activity are issued before each hurricane season by noted hurricane expert William M. Gray and his associates at Colorado State University, separately by forecasters with the U.
S. Government's Atmospheric Administration. Prior to and during the 2005 season, Gray issued four forecasts, each time increasing the predicted level of activity; the NOAA issued two forecasts, one shortly before the season and one two months into the season, drastically increasing the predicted level of activity in the second release. Nonetheless, all forecasts fell far short of the actual activity of the season. On December 3, 2004, Gray's team issued its first extended-range forecast for the 2005 season, predicting a above-average season. Additionally, the team predicted a increased chance of a major hurricane striking the East Coast of the United States and the Florida peninsula. Though the forecast predicted above-average activity, the level predicted was less than the 2004 season. On April 1, 2005, after confirming that El Niño conditions would not develop and his team revised the December forecast upward, expecting thirteen tropical storms instead of eleven and seven hurricanes instead of six.
In addition, the chance of a storm impacting the United States was raised slightly. On May 16, 2005, 16 days before the season began, NOAA issued its outlook for the 2005 season, forecasting a 70% chance of above-normal activity; the accumulated cyclone energy value for the season was predicted to be 120–190% of the median ACE of 87.5 × 104 kt2. Shortly thereafter, on May 31, the day before the season began, Gray's team revised its April forecast upwards to 15 named storms, 8 hurricanes, 4 major hurricanes. On August 2, after an extraordinarily active early season, the NOAA released an updated outlook on the remainder of the season raising the expected level of activity to numbers about double those of a normal season; the ACE value was now forecast to be 180 to 270% of the median. The NOAA noted a higher than normal confidence in the forecast of above-normal activity. On August 5, 2005, Gray and his associates issued their updated forecast. Although neither the NOAA nor Gray had forecast such high levels of activity the midseason outlooks fell far short of the actual level of activity.
The actual ACE would prove to be 248 × 104 kt2 — 277% of the median. On June 8, nearly two months earlier than when the 2004 season started, Tropical Storm Arlene formed in the western Caribbean, crossing Cuba before making landfall on the Florida Panhandle on June 11. Arlene caused only moderate damage, although one swimmer was caught in a riptide and drowned in Miami Beach, Florida. Tropical Storm Bret formed in the Bay of Campeche on June 28 and made landfall in Veracruz the next morning; the storm caused flooding which killed two people. Hurricane Cindy formed in the Gulf of Mexico on July 4. Thought to be a tropical storm, Cindy made landfall in Louisiana on July 5 as a minimal hurricane, dropping up to five in of rain, spawning several tornadoes, flooding some coastal areas including Coden and killing three people. Cindy
The eye is a region of calm weather at the center of strong tropical cyclones. The eye of a storm is a circular area 30–65 km in diameter, it is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds occur. The cyclone's lowest barometric pressure occurs in the eye and can be as much as 15 percent lower than the pressure outside the storm. In strong tropical cyclones, the eye is characterized by light winds and clear skies, surrounded on all sides by a towering, symmetric eyewall. In weaker tropical cyclones, the eye is less well defined and can be covered by the central dense overcast, an area of high, thick clouds that show up brightly on satellite imagery. Weaker or disorganized storms may feature an eyewall that does not encircle the eye or have an eye that features heavy rain. In all storms, the eye is the location of the storm's minimum barometric pressure—where the atmospheric pressure at sea level is the lowest. A typical tropical cyclone will have an eye of 30–65 km across situated at the geometric center of the storm.
The eye may be clear or have spotty low clouds, it may be filled with low- and mid-level clouds, or it may be obscured by the central dense overcast. There is, however little wind and rain near the center; this is in stark contrast to conditions in the eyewall. Due to the mechanics of a tropical cyclone, the eye and the air directly above it are warmer than their surroundings. While quite symmetric, eyes can be oblong and irregular in weakening storms. A large ragged eye is a non-circular eye which appears fragmented, is an indicator of a weak or weakening tropical cyclone. An open eye is an eye which can be circular, but the eyewall does not encircle the eye indicating a weakening, moisture-deprived cyclone. Both of these observations are used to estimate the intensity of tropical cyclones via Dvorak analysis. Eyewalls are circular. While typical mature storms have eyes that are a few dozen miles across intensifying storms can develop an small and circular eye, sometimes referred to as a pinhole eye.
Storms with pinhole eyes are prone to large fluctuations in intensity, provide difficulties and frustrations for forecasters. Small/minuscule eyes—those less than 10 nmi across—often trigger eyewall replacement cycles, where a new eyewall begins to form outside the original eyewall; this can take place anywhere from fifteen to hundreds of kilometers outside the inner eye. The storm develops two concentric eyewalls, or an "eye within an eye". In most cases, the outer eyewall begins to contract soon after its formation, which chokes off the inner eye and leaves a much larger but more stable eye. While the replacement cycle tends to weaken storms as it occurs, the new eyewall can contract quickly after the old eyewall dissipates, allowing the storm to re-strengthen; this may trigger another re-strengthen cycle of eyewall replacement. Eyes can range in size from 370 km to a mere 3.7 km across. While it is uncommon for storms with large eyes to become intense, it does occur in annular hurricanes. Hurricane Isabel was the eleventh most powerful North Atlantic hurricane in recorded history, sustained a large, 65–80 km -wide eye for a period of several days.
Tropical cyclones form from large, disorganized areas of disturbed weather in tropical regions. As more thunderstorms form and gather, the storm develops rainbands which start rotating around a common center; as the storm gains strength, a ring of stronger convection forms at a certain distance from the rotational center of the developing storm. Since stronger thunderstorms and heavier rain mark areas of stronger updrafts, the barometric pressure at the surface begins to drop, air begins to build up in the upper levels of the cyclone; this results in the formation of an upper level anticyclone, or an area of high atmospheric pressure above the central dense overcast. Most of this built up air flows outward anticyclonically above the tropical cyclone. Outside the forming eye, the anticyclone at the upper levels of the atmosphere enhances the flow towards the center of the cyclone, pushing air towards the eyewall and causing a positive feedback loop. However, a small portion of the built-up air, instead of flowing outward, flows inward towards the center of the storm.
This causes air pressure to build further, to the point where the weight of the air counteracts the strength of the updrafts in the center of the storm. Air begins to descend in the center of the storm, creating a rain-free area—a newly formed eye. There are many aspects of this process. Scientists do not know why a ring of convection forms around the center of circulation instead of on top of it, or why the upper-level anticyclone only ejects a portion of the excess air above the storm. Many theories exist as to the exact process by which the eye forms: all, known for sure is that the eye is necessary for tropical cyclones to achieve high wind speeds; the formation of an eye is always an indicator of increasing tropical cyclone organisation and strength. Because of this, forecasters watch developing storms for signs of eye formation. For storms with a clear eye, detection of the eye is as simple as looking at pictures from a weather satellite. However, for storms with a filled eye, or an eye covered by the central dense ove
United States dollar
The United States dollar is the official currency of the United States and its territories per the United States Constitution since 1792. In practice, the dollar is divided into 100 smaller cent units, but is divided into 1000 mills for accounting; the circulating paper money consists of Federal Reserve Notes that are denominated in United States dollars. Since the suspension in 1971 of convertibility of paper U. S. currency into any precious metal, the U. S. dollar is, de facto, fiat money. As it is the most used in international transactions, the U. S. dollar is the world's primary reserve currency. Several countries use it as their official currency, in many others it is the de facto currency. Besides the United States, it is used as the sole currency in two British Overseas Territories in the Caribbean: the British Virgin Islands and Turks and Caicos Islands. A few countries use the Federal Reserve Notes for paper money, while still minting their own coins, or accept U. S. dollar coins. As of June 27, 2018, there are $1.67 trillion in circulation, of which $1.62 trillion is in Federal Reserve notes.
Article I, Section 8 of the U. S. Constitution provides that the Congress has the power "To coin money". Laws implementing this power are codified at 31 U. S. C. § 5112. Section 5112 prescribes the forms; these coins are both designated in Section 5112 as "legal tender" in payment of debts. The Sacagawea dollar is one example of the copper alloy dollar; the pure silver dollar is known as the American Silver Eagle. Section 5112 provides for the minting and issuance of other coins, which have values ranging from one cent to 100 dollars; these other coins are more described in Coins of the United States dollar. The Constitution provides that "a regular Statement and Account of the Receipts and Expenditures of all public Money shall be published from time to time"; that provision of the Constitution is made specific by Section 331 of Title 31 of the United States Code. The sums of money reported in the "Statements" are being expressed in U. S. dollars. The U. S. dollar may therefore be described as the unit of account of the United States.
The word "dollar" is one of the words in the first paragraph of Section 9 of Article I of the Constitution. There, "dollars" is a reference to the Spanish milled dollar, a coin that had a monetary value of 8 Spanish units of currency, or reales. In 1792 the U. S. Congress passed a Coinage Act. Section 9 of that act authorized the production of various coins, including "DOLLARS OR UNITS—each to be of the value of a Spanish milled dollar as the same is now current, to contain three hundred and seventy-one grains and four sixteenth parts of a grain of pure, or four hundred and sixteen grains of standard silver". Section 20 of the act provided, "That the money of account of the United States shall be expressed in dollars, or units... and that all accounts in the public offices and all proceedings in the courts of the United States shall be kept and had in conformity to this regulation". In other words, this act designated the United States dollar as the unit of currency of the United States. Unlike the Spanish milled dollar, the U.
S. dollar is based upon a decimal system of values. In addition to the dollar the coinage act established monetary units of mill or one-thousandth of a dollar, cent or one-hundredth of a dollar, dime or one-tenth of a dollar, eagle or ten dollars, with prescribed weights and composition of gold, silver, or copper for each, it was proposed in the mid-1800s that one hundred dollars be known as a union, but no union coins were struck and only patterns for the $50 half union exist. However, only cents are in everyday use as divisions of the dollar. XX9 per gallon, e.g. $3.599, more written as $3.599⁄10. When issued in circulating form, denominations equal to or less than a dollar are emitted as U. S. coins while denominations equal to or greater than a dollar are emitted as Federal Reserve notes. Both one-dollar coins and notes are produced today, although the note form is more common. In the past, "paper money" was issued in denominations less than a dollar and gold coins were issued for circulation up to the value of $20.
The term eagle was used in the Coinage Act of 1792 for the denomination of ten dollars, subsequently was used in naming gold coins. Paper currency less than one dollar in denomination, known as "fractional currency", was sometimes pejoratively referred to as "shinplasters". In 1854, James Guthrie Secretary of the Treasury, proposed creating $100, $50 and $25 gold coins, which were referred to as a "Union", "Half Union", "Quarter Union", thus implying a denomination of 1 Union = $100. Today, USD notes are made from cotton fiber paper, unlike most common paper, made of wood fiber. U. S. coins are produced by the United States Mint. U. S. dollar banknotes are printed by the Bureau of Engraving and Printing and, since 1914, have been issued by t
Honduras the Republic of Honduras, is a country in Central America. In the past, it was sometimes referred to as "Spanish Honduras" to differentiate it from British Honduras, which became modern-day Belize; the republic of Honduras is bordered to the west by Guatemala, to the southwest by El Salvador, to the southeast by Nicaragua, to the south by the Pacific Ocean at the Gulf of Fonseca, to the north by the Gulf of Honduras, a large inlet of the Caribbean Sea. Honduras was home to several important Mesoamerican cultures, most notably the Maya, before the Spanish invaded in the sixteenth century; the Spanish introduced Roman Catholicism and the now predominant Spanish language, along with numerous customs that have blended with the indigenous culture. Honduras became independent in 1821 and has since been a republic, although it has endured much social strife and political instability, remains one of the poorest countries in the Western Hemisphere. In 1960, the northern part of what was the Mosquito Coast was transferred from Nicaragua to Honduras by the International Court of Justice.
The nation's economy is agricultural, making it vulnerable to natural disasters such as Hurricane Mitch in 1998. The lower class is agriculturally based while wealth is concentrated in the country's urban centers. Honduras has a Human Development Index of 0.625, classifying it as a nation with medium development. When the Index is adjusted for income inequality, its Inequality-adjusted Human Development Index is 0.443. Honduran society is predominantly Mestizo; the nation had a high political stability until its 2009 coup and again with the 2017 presidential election. Honduras has high levels of sexual violence. Honduras has a population exceeding 9 million, its northern portions are part of the Western Caribbean Zone, as reflected in the area's demographics and culture. Honduras is known for its rich natural resources, including minerals, tropical fruit, sugar cane, as well as for its growing textiles industry, which serves the international market; the literal meaning of the term "Honduras" is "depths" in Spanish.
The name could either refer to the bay of Trujillo as an anchorage, fondura in the Leonese dialect of Spanish, or to Columbus's alleged quote that "Gracias a Dios que hemos salido de esas Honduras". It was not until the end of the 16th century. Prior to 1580, Honduras referred to only the eastern part of the province, Higueras referred to the western part. Another early name is Guaymuras, revived as the name for the political dialogue in 2009 that took place in Honduras as opposed to Costa Rica. Hondurans are referred to as Catracho or Catracha in Spanish; the word was coined by Nicaraguans and derives from the last name of the Spanish Honduran General Florencio Xatruch, who in 1857 led Honduran armed forces against an attempted invasion by North American adventurer William Walker. The nickname is considered not derogatory. In pre-Columbian times, modern Honduras was part of the Mesoamerican cultural area. In the west, Mayan civilization flourished for hundreds of years; the dominant state within Honduras' borders was in Copán.
Copán fell with the other Lowland centres during the conflagrations of the Terminal Classic in the 9th century. The Maya of this civilization survive in western Honduras as the Ch'orti', isolated from their Choltian linguistic peers to the west. Remnants of other Pre-Columbian cultures are found throughout the country. Archaeologists have studied sites such as Naco and La Sierra in the Naco Valley, Los Naranjos on Lake Yojoa, Yarumela in the Comayagua Valley, La Ceiba and Salitron Viejo, Selin Farm and Cuyamel in the Aguan valley, Cerro Palenque, Curruste, Despoloncal in the lower Ulua river valley, many others. On his fourth and the final voyage to the New World in 1502, Christopher Columbus landed near the modern town of Trujillo, near Guaimoreto Lagoon, becoming the first European to visit the Bay Islands on the coast of Honduras. On 30 July 1502, Columbus sent his brother Bartholomew to explore the islands and Bartholomew encountered a Mayan trading vessel from Yucatán, carrying well-dressed Maya and a rich cargo.
Bartholomew's men stole the cargo they wanted and kidnapped the ship's elderly captain to serve as an interpreter in the first recorded encounter between the Spanish and the Maya. In March 1524, Gil González Dávila became the first Spaniard to enter Honduras as a conquistador. Followed by Hernán Cortés, who had brought forces down from Mexico. Much of the conquest took place in the following two decades, first by groups loyal to Cristóbal de Olid, by those loyal to Francisco de Montejo but most by those following Alvarado. In addition to Spanish resources, the conquerors relied on armed forces from Mexico—Tlaxcalans and Mexica armies of thousands who remained garrisoned in the region. Resistance to conquest was led in particular by Lempira. Many regions in the north of Honduras never fell to the Spanish, notably the Miskito Kingdom. After the Spanish conquest, Honduras became part of Spain's vast empire in the New World within the Kingdom of Guatemala. Trujillo and Gracias were the first city-capitals.
The Spanish ruled the region for three centuries. Honduras was organized as a province of the Kingdom of Guatemala and the capital was fixed, first at Trujillo on the Atlantic coast, at Comayagua, final
Atmospheric pressure, sometimes called barometric pressure, is the pressure within the atmosphere of Earth. The standard atmosphere is a unit of pressure defined as 1013.25 mbar, equivalent to 760 mmHg, 29.9212 inches Hg, or 14.696 psi. The atm unit is equivalent to the mean sea-level atmospheric pressure on Earth, that is, the Earth's atmospheric pressure at sea level is 1 atm. In most circumstances atmospheric pressure is approximated by the hydrostatic pressure caused by the weight of air above the measurement point; as elevation increases, there is less overlying atmospheric mass, so that atmospheric pressure decreases with increasing elevation. Pressure measures force per unit area, with SI units of Pascals. On average, a column of air with a cross-sectional area of 1 square centimetre, measured from mean sea level to the top of Earth's atmosphere, has a mass of about 1.03 kilogram and exerts a force or "weight" of about 10.1 newtons or 2.37 lbf, resulting in a pressure at sea level of about 10.1 N/cm2 or 101 kN/m2.
A column of air with a cross-sectional area of 1 in2 would have a mass of about 6.65 kg and a weight of about 65.4 N or 14.7 lbf, resulting in a pressure of 10.1 N/cm2 or 14.7 lbf/in2. Atmospheric pressure is caused by the gravitational attraction of the planet on the atmospheric gases above the surface, is a function of the mass of the planet, the radius of the surface, the amount and composition of the gases and their vertical distribution in the atmosphere, it is modified by the planetary rotation and local effects such as wind velocity, density variations due to temperature and variations in composition. The mean sea-level pressure is the average atmospheric pressure at mean sea level; this is the atmospheric pressure given in weather reports on radio and newspapers or on the Internet. When barometers in the home are set to match the local weather reports, they measure pressure adjusted to sea level, not the actual local atmospheric pressure; the altimeter setting in aviation is an atmospheric pressure adjustment.
Average sea-level pressure is 1013.25 mbar. In aviation, weather reports, QNH is transmitted around the world in millibars or hectopascals, except in the United States and Colombia where it is reported in inches of mercury; the United States and Canada report sea-level pressure SLP, adjusted to sea level by a different method, in the remarks section, not in the internationally transmitted part of the code, in hectopascals or millibars. However, in Canada's public weather reports, sea level pressure is instead reported in kilopascals. In the US weather code remarks, three digits are all; the highest sea-level pressure on Earth occurs in Siberia, where the Siberian High attains a sea-level pressure above 1050 mbar, with record highs close to 1085 mbar. The lowest measurable sea-level pressure is found at the centers of tropical cyclones and tornadoes, with a record low of 870 mbar. Surface pressure is the atmospheric pressure at a location on Earth's surface, it is directly proportional to the mass of air over that location.
For numerical reasons, atmospheric models such as general circulation models predict the nondimensional logarithm of surface pressure. The average value of surface pressure on Earth is 985 hPa; this is in contrast to mean sea-level pressure, which involves the extrapolation of pressure to sea-level for locations above or below sea-level. The average pressure at mean sea-level in the International Standard Atmosphere is 1013.25 hPa, or 1 atmosphere, or 29.92 inches of mercury. Pressure and the acceleration due to gravity, are related by P = F/A = /A, where A is surface area. Atmospheric pressure is thus proportional to the weight per unit area of the atmospheric mass above that location. Pressure on Earth varies with the altitude of the surface. Pressure varies smoothly from the Earth's surface to the top of the mesosphere. Although the pressure changes with the weather, NASA has averaged the conditions for all parts of the earth year-round; as altitude increases, atmospheric pressure decreases.
One can calculate the atmospheric pressure at a given altitude. Temperature and humidity affect the atmospheric pressure, it is necessary to know these to compute an accurate figure; the graph at right was developed for a temperature of 15 °C and a relative humidity of 0%. At low altitudes above sea level, the pressure decreases by about 1.2 kPa for every 100 metres. For higher altitudes within the troposphere, the following equation relates atmospheric pressure p to altitude h p = p 0 ⋅ g ⋅ M R 0 ⋅