Inn
Inns are establishments or buildings where travelers can seek lodging and food and drink. They are located in the country or along a highway. Inns in Europe were first established when the Romans built their system of Roman roads two millennia ago; some inns in Europe are several centuries old. In addition to providing for the needs of travelers, inns traditionally acted as community gathering places. Inns in Europe provided not only food and lodging, but stabling and fodder for the travelers' horses. Famous London examples of inns include the Tabard. There is however no longer other kinds of establishment. Many pubs use the name "inn", either because they are long established and may have been coaching inns, or to summon up a particular kind of image. Inns were like bed and breakfasts, with a community dining room, used for town meetings or rented for wedding parties; the front, facing the road was welcoming for travelers. The back usually had at least one livery barn for travelers to keep their horses.
There were not lobbies as in modern inns. Many inns were large estates that had extra rooms for renting. During the 19th century the inn played a major role in the growing transportation system of England. Industry was on the rise and people were traveling more in order to keep and maintain business; the English Inn was considered an important part of English infrastructure as it helped maintain a smooth flow of travel throughout the country. As modes of transport have evolved, tourist lodging has adapted to serve each generation of traveller. A stagecoach made frequent stops at roadside coaching inns for water and horses. A passenger train stops only at designated stations in the city centre, around which were built grand railway hotels. Motorcar traffic on old-style two-lane highways may pause at any camp, cabin court or motel along the way, while freeway traffic is restricted to access from designated off-ramps to side roads which become crowded with hotel chain operators; the original functions of an inn are now split among separate establishments, such as hotels and motels, all of which might provide the traditional functions of an inn but which focus more on lodging customers than on other services.
The lodging aspect of the word inn lives on in hotel brand names like Holiday Inn, in some laws that refer to lodging operators as innkeepers. The Inns of Court in London were once accommodations for members of the legal profession. Other forms of inn exist throughout the world. Among them are the honjin and ryokan of Japan, caravanserai of the Central Asia and Middle East, Jiuguan in ancient China. In Asia Minor, during the periods of rule by the Seljuq and Ottoman Turks, impressive structures functioning as inns were built because it was thought that inns were significant; these inns provided accommodation for people and their vehicles or animals and served as a resting place for people, whether travelling on foot or by other means. These inns were built between towns; these structures were called caravansarais which were inns with large courtyards with ample supplies of water for both drinking and other uses. They would routinely contain a café in addition to supplies of food and fodder. After the caravans traveled a while they would take a break at these caravansarais, spend the night there to rest both themselves and their animals.
The term "inn" characterized a rural hotel which provided lodging and refreshments, accommodations for travelers' horses. To capitalize on this nostalgic image many lower end and middling modern motor hotel operators seek to distance themselves from similar motels by styling themselves "inns", regardless of services and accommodations provided. Examples are Holiday Inn, Comfort Inn, Days Inn and Knights Inn; the term inn is retained in its historic use in many laws governing motels and hotels known as "innkeeper's acts", or refer to hôteliers and motel operators as "innkeepers" in the body of the legislation These laws define the innkeepers' liability for valuables entrusted to them by clients and determine whether an innkeeper holds any lien against such goods. In some jurisdictions, an offence named as "defrauding an innkeeper" prohibits fraudulently obtaining "food, lodging, or other accommodation at any hotel, boarding house, or eating house". Burke, Thomas The Book of the Inn: being two hundred pictures of the English inn from the earliest times to the coming of the railway hotel.
London: Constable Burke, Thomas The English Inn. London: Herbert Jenkins --do.-- --do.--Revised. London: Herbert Jenkins Everitt, Alan "The English Urban Inn", in his: Landscape and Community in England. London: Hambledon Press ISBN 0907628427 (The Oxford Companion to Local
Eldorado National Forest
Eldorado National Forest is a U. S. National Forest located in eastern California. Most of the forest lies in El Dorado County. In descending order of land area the others counties are: Amador and Placer counties in California; the forest is bordered on the north by the Tahoe National Forest, on the east by the Lake Tahoe Basin Management Unit, on the southeast by the Humboldt-Toiyabe National Forest, to the south by the Stanislaus National Forest. Eldorado National Forest headquarters are located in California. There are local ranger district offices in Camino, Georgetown and Pollock Pines. A complicated ownership pattern exists; the parcels of Other Ownership are isolated and surrounded on all sides by government land. An opposite pattern occurs outside of the Forest Boundary where several small scattered pieces of National Forest lands are separated from the main body and surrounded by lands of Other Ownership. Gross area: 786,994 acres Other ownership: 190,270 acres Net area: 596,724 acres The Forest ranges in elevation from 1,000 feet in the foothills to more than 10,000 feet above sea level along the Sierra crest.
The mountainous topography is broken by the steep canyons of the Mokelumne, Cosumnes and Rubicon rivers. Plateaus of moderate relief are located between these steep canyons; the Desolation Wilderness is located within the forest's boundaries, as is most of the Mokelumne Wilderness. A cool montane version of Mediterranean climate extends over most of the forest with warm, dry summers and cold, wet winters. Annual precipitation: 40 to 70 inches on average. Precipitation falls from October through April. Temperature range: 0 °F in winter to 100 °F in the summer. Snow pack: 5 to 10 feet on average, can be as high as 15 feet. Snow is present from December to May at elevations above 6,000 feet. A wide variety of hardwoods, shrubs, native grasses, forbs are represented in the various Eldorado National Forest ecosystems; the principal plant communities found here are: Interior chaparral Oak woodlands Lower Montane forest — indicator species: Pinus ponderosa - Ponderosa Pine, Pinus jeffreyi - Jeffrey Pine Upper Montane forest — indicator species: Abies magnifica - Red Fir Subalpine zone.
Old-growth forests totaling 122,000 acres have been identified in the Eldorado National Forest, consisting of: Sierra Nevada mixed conifer forestsCoast Douglas-fir Ponderosa Pine White Fir andLodgepole Pine forests Red Fir forests The major commercial Forest species are White Fir, Red Fir, Ponderosa Pine, Jeffrey pine, Sugar Pine, Douglas Fir, Incense Cedar. Water is a major resource of the Eldorado National Forest; the forest receives about 56 inches of precipitation annually. Average annual runoff is about 29 inches; this is equal to an annual water yield of 2.4 acre feet per acre. 611 miles of fishable streams in four major drainage systems: Middle Fork of the American River, South Fork of the American River, Cosumnes River, North Fork of the Mokelumne River. 297 lakes and reservoirs, which total 11,994 acres. 11 large reservoirs account for 9,000 acres. The rest are small, high mountain lakes; the Eldorado National Forest has a high density of transportation routes, with 2,367 miles of roads, 349 miles of trails.
Roads under Forest Service jurisdiction total 2,158 miles. There are 209 miles of county roads, 400 miles of private roads within the National Forest boundaries; the forest was established on July 1910 from a portion of Tahoe National Forest and other lands. List of plants of the Sierra Nevada Index: Fauna of the Sierra Nevada The forest was formed by the last ice age. Official website Gorp.com: Eldorado National Forest
Mediterranean climate
A Mediterranean climate or dry summer climate is characterized by rainy winters and dry summers, with less than 40 mm of precipitation for at least three summer months. While the climate receives its name from the Mediterranean Basin, these are located on the western coasts of continents, between 30 and 45 degrees north and south of the equator between oceanic climates towards the poles, semi-arid and arid climates towards the equator. In essence, due to the seasonal shift of the subtropical high-pressure belts with the apparent movement of the Sun, a Mediterranean climate is an intermediate type between these other climates, with winters warmer and drier than oceanic climates and summers imitating sunny weather in semi-arid and arid climates; the resulting vegetation of Mediterranean climates are the garrigue or maquis in the Mediterranean Basin, the chaparral in California, the fynbos in South Africa, the mallee in Australia, the matorral in Chile. Areas with this climate are where the so-called "Mediterranean trinity" of agricultural products have traditionally developed: wheat and olive.
Most large, historic cities of the Mediterranean basin lie within Mediterranean climatic zones, including Algiers, Beirut, İzmir, Marseille, Rome and Valencia. Examples of major cities with Mediterranean climates that lie outside of the historic Mediterranean basin include major examples as Adelaide, Cape Town, Dushanbe, Los Angeles, Perth, San Francisco and Victoria. Under the Köppen climate classification, "hot dry-summer" climates and "cool dry-summer" climates are referred to as "Mediterranean". Under the Köppen climate system, the first letter indicates the climate group. Temperate climates or "C" zones have an average temperature above 0 °C, but below 18 °C, in their coolest months; the second letter indicates the precipitation pattern. Köppen has defined a dry summer month as a month with less than 30 mm of precipitation and with less than one-third that of the wettest winter month. Some, use a 40 mm level; the third letter indicates the degree of summer heat: "a" represents an average temperature in the warmest month above 22 °C, while "b" indicates the average temperature in the warmest month below 22 °C.
Under the Köppen classification, dry-summer climates occur on the western sides of continents. Csb zones in the Köppen system include areas not associated with Mediterranean climates but with Oceanic climates, such as much of the Pacific Northwest, much of southern Chile, parts of west-central Argentina, parts of New Zealand. Additional highland areas in the subtropics meet Cs requirements, though they, are not associated with Mediterranean climates, as do a number of oceanic islands such as Madeira, the Juan Fernández Islands, the western part of the Canary Islands, the eastern part of the Azores. Under Trewartha's modified Köppen climate classification, the two major requirements for a Cs climate are revised. Under Trewartha's system, at least eight months must have average temperatures of 10 °C or higher, the average annual precipitation must not exceed 900 mm. Thus, under this system, many Csb zones in the Köppen system become Do, the rare Csc zones become Eo, with only the classic dry-summer to warm winter, low annual rainfall locations included in the Mediterranean type climate.
During summer, regions of Mediterranean climate are influenced by cold ocean currents which keep the weather in the region dry and pleasant. Similar to desert climates, in many Mediterranean climates there is a strong diurnal character to daily temperatures in the warm summer months due to strong heating during the day from sunlight and rapid cooling at night. In winter, Mediterranean climate zones are no longer influenced by the cold ocean currents and therefore warmer water settles near land and causes clouds to form and rainfall becomes much more likely; as a result, areas with this climate receive all of their precipitation during their winter and spring seasons, may go anywhere from 3 to 6 months during the summer without having any significant precipitation. In the lower latitudes, precipitation decreases in both the winter and summer because they are closer to the Horse latitudes, thus bringing smaller amounts of rain. Toward the polar latitudes, total moisture increases; the rainfall tends to be more evenly distributed throughout the year in Southern Europe, while in the Eastern Mediterranean and in Southern California the summer is nearly or dry.
In places where evapotranspiration is higher, steppe climates tend to prevail, but still follow the weather pattern of the Mediterranean climate. The majority of the regions with Mediterranean climates have mild winters and warm summers; however winter and summer temperatures can vary between different regions with a Mediterranean climate. For instance, in the case of winters and Los Angeles experience mild temperatures in the winter, with frost and snowfall unknown, whereas Tashkent has colder winters with annual frosts and snowfall. Or to consider summer, Athens experiences rather high temperatures in that season. In contrast, San Francisco has cool summers with daily highs around 21 °C due to
ZIP Code
A ZIP Code is a postal code used by the United States Postal Service in a system it introduced in 1963. The term ZIP is an acronym for Zone Improvement Plan; the basic format consists of five digits. An extended ZIP+4 code was introduced in 1983 which includes the five digits of the ZIP Code, followed by a hyphen and four additional digits that reference a more specific location; the term ZIP Code was registered as a servicemark by the U. S. Postal Service, but its registration has since expired; the early history and context of postal codes began with postal district/zone numbers. The United States Post Office Department implemented postal zones for numerous large cities in 1943. For example: The "16" was the number of the postal zone in the specific city. By the early 1960s, a more organized system was needed, non-mandatory five-digit ZIP Codes were introduced nationwide on July 1, 1963; the USPOD issued its Publication 59: Abbreviations for Use with ZIP Code on October 1, 1963, with the list of two-letter state abbreviations which are written with both letters capitalized.
An earlier list in June had proposed capitalized abbreviations ranging from two to five letters. According to Publication 59, the two-letter standard was "based on a maximum 23-position line, because this has been found to be the most universally acceptable line capacity basis for major addressing systems", which would be exceeded by a long city name combined with a multi-letter state abbreviation, such as "Sacramento, Calif." along with the ZIP Code. The abbreviations have remained unchanged, with the exception of Nebraska, changed from NB to NE in 1969 at the request of the Canadian postal administration, to avoid confusion with the Canadian province of New Brunswick. Robert Moon is considered the father of the ZIP Code; the post office only credits Moon with the first three digits of the ZIP Code, which describe the sectional center facility or "sec center." An SCF is a central mail processing facility with those three digits. The fourth and fifth digits, which give a more precise locale within the SCF, were proposed by Henry Bentley Hahn Sr.
The SCF sorts mail to all post offices with those first three digits in their ZIP Codes. The mail is sorted according to the final two digits of the ZIP Code and sent to the corresponding post offices in the early morning. Sectional centers do not deliver mail and are not open to the public, most of their employees work the night shift. Mail picked up at post offices is sent to their own SCF in the afternoon, where the mail is sorted overnight. In the case of large cities, the last two digits coincide with the older postal zone number thus: In 1967, these became mandatory for second- and third-class bulk mailers, the system was soon adopted generally; the United States Post Office used a cartoon character, which it called Mr. ZIP, to promote the use of the ZIP Code, he was depicted with a legend such as "USE ZIP CODE" in the selvage of panes of postage stamps or on the covers of booklet panes of stamps. In 1971 Elmira Star-Gazette reporter Dick Baumbach found out the White House was not using a ZIP Code on its envelopes.
Herb Klein, special assistant to President Nixon, responded by saying the next printing of envelopes would include the ZIP Code. In 1983, the U. S. Postal Service introduced an expanded ZIP Code system that it called ZIP+4 called "plus-four codes", "add-on codes", or "add-ons". A ZIP+4 Code uses the basic five-digit code plus four additional digits to identify a geographic segment within the five-digit delivery area, such as a city block, a group of apartments, an individual high-volume receiver of mail, a post office box, or any other unit that could use an extra identifier to aid in efficient mail sorting and delivery. However, initial attempts to promote universal use of the new format met with public resistance and today the plus-four code is not required. In general, mail is read by a multiline optical character reader that instantly determines the correct ZIP+4 Code from the address—along with the more specific delivery point—and sprays an Intelligent Mail barcode on the face of the mail piece that corresponds to 11 digits—nine for the ZIP+4 Code and two for the delivery point.
For Post Office Boxes, the general rule is. The add-on code is one of the following: the last four digits of the box number, zero plus the last three digits of the box number, or, if the box number consists of fewer than four digits, enough zeros are attached to the front of the box number to produce a four-digit number. However, there is no uniform rule, so the ZIP+4 Code must be looked up individually for each box; the ZIP Code is translated into an Intelligent Mail barcode, printed on the mailpiece to make it easier for automated machines to sort. A barcode can be printed by the sender, it is better to let the post office put one on. In general, the post office uses OCR technology, though in some cases a human might have to read and enter the address. Customers who send bulk mail can get a discount on postage if they have printed the barcode themselves and have presorted the mai
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
Cattle
Cattle—colloquially cows—are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, are most classified collectively as Bos taurus. Cattle are raised as livestock for meat, for milk, for hides, which are used to make leather, they are used as riding animals and draft animals. Another product of cattle is dung, which can be used to create fuel. In some regions, such as parts of India, cattle have significant religious meaning. Cattle small breeds such as the Miniature Zebu, are kept as pets. Around 10,500 years ago, cattle were domesticated from as few as 80 progenitors in central Anatolia, the Levant and Western Iran. According to an estimate from 2011, there are 1.4 billion cattle in the world. In 2009, cattle became one of the first livestock animals to have a mapped genome; some consider cattle the oldest form of wealth, cattle raiding one of the earliest forms of theft. Cattle were identified as three separate species: Bos taurus, the European or "taurine" cattle.
The aurochs is ancestral to both taurine cattle. These have been reclassified as one species, Bos taurus, with three subspecies: Bos taurus primigenius, Bos taurus indicus, Bos taurus taurus. Complicating the matter is the ability of cattle to interbreed with other related species. Hybrid individuals and breeds exist, not only between taurine cattle and zebu, but between one or both of these and some other members of the genus Bos – yaks and gaur. Hybrids such as the beefalo breed can occur between taurine cattle and either species of bison, leading some authors to consider them part of the genus Bos, as well; the hybrid origin of some types may not be obvious – for example, genetic testing of the Dwarf Lulu breed, the only taurine-type cattle in Nepal, found them to be a mix of taurine cattle and yak. However, cattle cannot be hybridized with more distantly related bovines such as water buffalo or African buffalo; the aurochs ranged throughout Europe, North Africa, much of Asia. In historical times, its range became restricted to Europe, the last known individual died in Mazovia, Poland, in about 1627.
Breeders have attempted to recreate cattle of similar appearance to aurochs by crossing traditional types of domesticated cattle, creating the Heck cattle breed. The noun cattle encompasses both sexes; the singular, technically means the female, the male being bull. The plural form cows is sometimes used colloquially to refer to both sexes collectively, as e.g. in a herd, but that usage can be misleading as the speaker's intent may indeed be just the females. The bovine species per se is dimorphic. Cattle did not originate as the term for bovine animals, it was borrowed from Anglo-Norman catel, itself from medieval Latin capitale'principal sum of money, capital', itself derived in turn from Latin caput'head'. Cattle meant movable personal property livestock of any kind, as opposed to real property; the word is a variant of chattel and related to capital in the economic sense. The term replaced earlier Old English feoh ` property', which survives today as fee; the word "cow" came via Anglo-Saxon cū, from Common Indo-European gʷōus = "a bovine animal", compare Persian: gâv, Sanskrit: go-, Welsh: buwch.
The plural cȳ became ki or kie in Middle English, an additional plural ending was added, giving kine, but kies and others. This is the origin of the now archaic English plural, "kine"; the Scots language singular is coo or cou, the plural is "kye". In older English sources such as the King James Version of the Bible, "cattle" refers to livestock, as opposed to "deer" which refers to wildlife. "Wild cattle" may refer to undomesticated species of the genus Bos. Today, when used without any other qualifier, the modern meaning of "cattle" is restricted to domesticated bovines. In general, the same words are used in different parts of the world, but with minor differences in the definitions; the terminology described here contrasts the differences in definition between the United Kingdom and other British-influenced parts of the world such as Canada, New Zealand and the United States. An "intact" adult male is called a bull. A wild, unmarked bull is known as a micky in Australia. An unbranded bovine of either sex is called a maverick in the Canada.
An adult female that has had a calf is a cow. A young female before she has had a calf of her own and is under three years of age is called a heifer. A young female that has had only one calf is called a first-calf heifer. Young cattle of both sexes are called calves until they are weaned weaners until they are a year old in some areas. After that, they are referred to as stirks if between one and two years of age. A castrated male is called a steer in the United States.
Precipitation
In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation include drizzle, sleet, snow and hail. Precipitation occurs when a portion of the atmosphere becomes saturated with water vapor, so that the water condenses and "precipitates", thus and mist are not precipitation but suspensions, because the water vapor does not condense sufficiently to precipitate. Two processes acting together, can lead to air becoming saturated: cooling the air or adding water vapor to the air. Precipitation forms as smaller droplets coalesce via collision with other rain drops or ice crystals within a cloud. Short, intense periods of rain in scattered locations are called "showers."Moisture, lifted or otherwise forced to rise over a layer of sub-freezing air at the surface may be condensed into clouds and rain. This process is active when freezing rain occurs. A stationary front is present near the area of freezing rain and serves as the foci for forcing and rising air.
Provided necessary and sufficient atmospheric moisture content, the moisture within the rising air will condense into clouds, namely stratus and cumulonimbus. The cloud droplets will grow large enough to form raindrops and descend toward the Earth where they will freeze on contact with exposed objects. Where warm water bodies are present, for example due to water evaporation from lakes, lake-effect snowfall becomes a concern downwind of the warm lakes within the cold cyclonic flow around the backside of extratropical cyclones. Lake-effect snowfall can be locally heavy. Thundersnow is possible within lake effect precipitation bands. In mountainous areas, heavy precipitation is possible where upslope flow is maximized within windward sides of the terrain at elevation. On the leeward side of mountains, desert climates can exist due to the dry air caused by compressional heating. Most precipitation is caused by convection; the movement of the monsoon trough, or intertropical convergence zone, brings rainy seasons to savannah climes.
Precipitation is a major component of the water cycle, is responsible for depositing the fresh water on the planet. 505,000 cubic kilometres of water falls as precipitation each year. Given the Earth's surface area, that means the globally averaged annual precipitation is 990 millimetres, but over land it is only 715 millimetres. Climate classification systems such as the Köppen climate classification system use average annual rainfall to help differentiate between differing climate regimes. Precipitation may occur on other celestial bodies, e.g. when it gets cold, Mars has precipitation which most takes the form of frost, rather than rain or snow. Precipitation is a major component of the water cycle, is responsible for depositing most of the fresh water on the planet. 505,000 km3 of water falls as precipitation each year, 398,000 km3 of it over the oceans. Given the Earth's surface area, that means the globally averaged annual precipitation is 990 millimetres. Mechanisms of producing precipitation include convective and orographic rainfall.
Convective processes involve strong vertical motions that can cause the overturning of the atmosphere in that location within an hour and cause heavy precipitation, while stratiform processes involve weaker upward motions and less intense precipitation. Precipitation can be divided into three categories, based on whether it falls as liquid water, liquid water that freezes on contact with the surface, or ice. Mixtures of different types of precipitation, including types in different categories, can fall simultaneously. Liquid forms of precipitation include drizzle. Rain or drizzle that freezes on contact within a subfreezing air mass is called "freezing rain" or "freezing drizzle". Frozen forms of precipitation include snow, ice needles, ice pellets and graupel; the dew point is the temperature to which a parcel must be cooled in order to become saturated, condenses to water. Water vapor begins to condense on condensation nuclei such as dust and salt in order to form clouds. An elevated portion of a frontal zone forces broad areas of lift, which form clouds decks such as altostratus or cirrostratus.
Stratus is a stable cloud deck which tends to form when a cool, stable air mass is trapped underneath a warm air mass. It can form due to the lifting of advection fog during breezy conditions. There are four main mechanisms for cooling the air to its dew point: adiabatic cooling, conductive cooling, radiational cooling, evaporative cooling. Adiabatic cooling occurs when air expands; the air can rise due to convection, large-scale atmospheric motions, or a physical barrier such as a mountain. Conductive cooling occurs when the air comes into contact with a colder surface by being blown from one surface to another, for example from a liquid water surface to colder land. Radiational cooling occurs due to the emission of infrared radiation, either by the air or by the surface underneath. Evaporative cooling occurs when moisture is added to the air through evaporation, which forces the air temperature to cool to its wet-bulb temperature, or until it reaches saturation; the main ways water vapor is added to the air are: wind convergence into areas of upward motion, precipitation or virga falling from above, daytime heating evaporating water from the surface of oceans, water bodies or wet lan
United States
California
