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Albedo
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Examples of terrestrial albedo effects
Aerosols (very fine particles/droplets in the atmosphere) have both direct and indirect effects on Earth's radiative balance. The direct (albedo) effect is generally to cool the planet; the indirect effect (the particles act as cloud condensation nuclei and thereby change cloud properties) is less certain. As per Spracklen et al. the effects are:
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Examples of terrestrial albedo effects
In extremely polluted cities like Delhi, aerosol pollutants influence local weather and induce an urban cool island effect during the day.
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Examples of terrestrial albedo effects
Another albedo-related effect on the climate is from black carbon particles. The size of this effect is difficult to quantify: the Intergovernmental Panel on Climate Change estimates that the global mean radiative forcing for black carbon aerosols from fossil fuels is +0.2 W m, with a range +0.1 to +0.4 W m. Black carbon is a bigger cause of the melting of the polar ice cap in the Arctic than carbon dioxide due to its effect on the albedo.
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Astronomical albedo
In astronomy, the term albedo can be defined in several different ways, depending upon the application and the wavelength of electromagnetic radiation involved.
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Astronomical albedo
The albedos of planets, satellites and minor planets such as asteroids can be used to infer much about their properties. The study of albedos, their dependence on wavelength, lighting angle ("phase angle"), and variation in time composes a major part of the astronomical field of photometry. For small and far objects that cannot be resolved by telescopes, much of what we know comes from the study of their albedos. For example, the absolute albedo can indicate the surface ice content of outer Solar System objects, the variation of albedo with phase angle gives information about regolith properties, whereas unusually high radar albedo is indicative of high metal content in asteroids.
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Astronomical albedo
Enceladus, a moon of Saturn, has one of the highest known optical albedos of any body in the Solar System, with an albedo of 0.99. Another notable high-albedo body is Eris, with an albedo of 0.96. Many small objects in the outer Solar System and asteroid belt have low albedos down to about 0.05. A typical comet nucleus has an albedo of 0.04. Such a dark surface is thought to be indicative of a primitive and heavily space weathered surface containing some organic compounds.
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Astronomical albedo
The overall albedo of the Moon is measured to be around 0.14, but it is strongly directional and non-Lambertian, displaying also a strong opposition effect. Although such reflectance properties are different from those of any terrestrial terrains, they are typical of the regolith surfaces of airless Solar System bodies.
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Astronomical albedo
Two common optical albedos that are used in astronomy are the (V-band) geometric albedo (measuring brightness when illumination comes from directly behind the observer) and the Bond albedo (measuring total proportion of electromagnetic energy reflected). Their values can differ significantly, which is a common source of confusion.
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Astronomical albedo
In detailed studies, the directional reflectance properties of astronomical bodies are often expressed in terms of the five Hapke parameters which semi-empirically describe the variation of albedo with phase angle, including a characterization of the opposition effect of regolith surfaces. One of these five parameters is yet another type of albedo called the single-scattering albedo. It is used to define scattering of electromagnetic waves on small particles. It depends on properties of the material (refractive index), the size of the particle, and the wavelength of the incoming radiation.
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Astronomical albedo
An important relationship between an object's astronomical (geometric) albedo, absolute magnitude and diameter is given by:
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Astronomical albedo
where A {\displaystyle A} is the astronomical albedo, D {\displaystyle D} is the diameter in kilometers, and H {\displaystyle H} is the absolute magnitude.
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Astronomical albedo
In planetary radar astronomy, a microwave (or radar) pulse is transmitted toward a planetary target (e.g. Moon, asteroid, etc.) and the echo from the target is measured. In most instances, the transmitted pulse is circularly polarized and the received pulse is measured in the same sense of polarization as the transmitted pulse (SC) and the opposite sense (OC). The echo power is measured in terms of radar cross-section, σ O C {\displaystyle {\sigma }_{OC}} , σ S C {\displaystyle {\sigma }_{SC}} , or σ T {\displaystyle {\sigma }_{T}} (total power, SC + OC) and is equal to the cross-sectional area of a metallic sphere (perfect reflector) at the same distance as the target that would return the same echo power.
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Astronomical albedo
Those components of the received echo that return from first-surface reflections (as from a smooth or mirror-like surface) are dominated by the OC component as there is a reversal in polarization upon reflection. If the surface is rough at the wavelength scale or there is significant penetration into the regolith, there will be a significant SC component in the echo caused by multiple scattering.
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Astronomical albedo
For most objects in the solar system, the OC echo dominates and the most commonly reported radar albedo parameter is the (normalized) OC radar albedo (often shortened to radar albedo):
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Astronomical albedo
where the denominator is the effective cross-sectional area of the target object with mean radius, r {\displaystyle r} . A smooth metallic sphere would have σ ^ OC = 1 {\displaystyle {\hat {\sigma }}_{\text{OC}}=1} .
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Astronomical albedo
The values reported for the Moon, Mercury, Mars, Venus, and Comet P/2005 JQ5 are derived from the total (OC+SC) radar albedo reported in those references.
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Astronomical albedo
In the event that most of the echo is from first surface reflections ( σ ^ OC < 0.1 {\displaystyle {\hat {\sigma }}_{\text{OC}}<0.1} or so), the OC radar albedo is a first-order approximation of the Fresnel reflection coefficient (aka reflectivity) and can be used to estimate the bulk density of a planetary surface to a depth of a meter or so (a few wavelengths of the radar wavelength which is typically at the decimeter scale) using the following empirical relationships:
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History
The term albedo was introduced into optics by Johann Heinrich Lambert in his 1760 work Photometria.
A
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A, or a, is the first letter and the first vowel of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is a (pronounced /ˈeɪ/), plural aes. It is similar in shape to the Ancient Greek letter Alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version can be written in two forms: the double-storey a and single-storey ɑ. The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type.
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In English grammar, "a", and its variant "an", are indefinite articles.
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History
The earliest known certain ancestor of "A" is aleph (also written 'aleph), the first letter of the Phoenician alphabet, which consisted entirely of consonants (for that reason, it is also called an abjad to distinguish it from a true alphabet). In turn, the ancestor of aleph may have been a pictogram of an ox head in proto-Sinaitic script influenced by Egyptian hieroglyphs, styled as a triangular head with two horns extended.
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History
When the ancient Greeks adopted the alphabet, they had no use for a letter to represent the glottal stop—the consonant sound that the letter denoted in Phoenician and other Semitic languages, and that was the first phoneme of the Phoenician pronunciation of the letter—so they used their version of the sign to represent the vowel /a/, and called it by the similar name of alpha. In the earliest Greek inscriptions after the Greek Dark Ages, dating to the eighth century BC, the letter rests upon its side, but in the Greek alphabet of later times it generally resembles the modern capital letter, although many local varieties can be distinguished by the shortening of one leg, or by the angle at which the cross line is set.
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History
The Etruscans brought the Greek alphabet to their civilization in the Italian Peninsula and left the letter unchanged. The Romans later adopted the Etruscan alphabet to write the Latin language, and the resulting letter was preserved in the Latin alphabet that would come to be used to write many languages, including English.
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History
During Roman times, there were many variant forms of the letter "A". First was the monumental or lapidary style, which was used when inscribing on stone or other "permanent" media. There was also a cursive style used for everyday or utilitarian writing, which was done on more perishable surfaces. Due to the "perishable" nature of these surfaces, there are not as many examples of this style as there are of the monumental, but there are still many surviving examples of different types of cursive, such as majuscule cursive, minuscule cursive, and semicursive minuscule. Variants also existed that were intermediate between the monumental and cursive styles. The known variants include the early semi-uncial, the uncial, and the later semi-uncial.
A
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History
At the end of the Roman Empire (5th century AD), several variants of the cursive minuscule developed through Western Europe. Among these were the semicursive minuscule of Italy, the Merovingian script in France, the Visigothic script in Spain, and the Insular or Anglo-Irish semi-uncial or Anglo-Saxon majuscule of Great Britain. By the ninth century, the Caroline script, which was very similar to the present-day form, was the principal form used in book-making, before the advent of the printing press. This form was derived through a combining of prior forms.
A
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History
15th-century Italy saw the formation of the two main variants that are known today. These variants, the Italic and Roman forms, were derived from the Caroline Script version. The Italic form, also called script a, is used in most current handwriting; it consists of a circle and vertical stroke on the right ("ɑ"). This slowly developed from the fifth-century form resembling the Greek letter tau in the hands of medieval Irish and English writers. The Roman form is used in most printed material; it consists of a small loop with an arc over it ("a"). Both derive from the majuscule (capital) form. In Greek handwriting, it was common to join the left leg and horizontal stroke into a single loop, as demonstrated by the uncial version shown. Many fonts then made the right leg vertical. In some of these, the serif that began the right leg stroke developed into an arc, resulting in the printed form, while in others it was dropped, resulting in the modern handwritten form. Graphic designers refer to the Italic and Roman forms as "single decker a" and "double decker a" respectively.
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History
Italic type is commonly used to mark emphasis or more generally to distinguish one part of a text from the rest (set in Roman type). There are some other cases aside from italic type where script a ("ɑ"), also called Latin alpha, is used in contrast with Latin "a" (such as in the International Phonetic Alphabet).
A
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Use in writing systems
In modern English orthography, the letter ⟨a⟩ represents at least seven different vowel sounds:
A
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Use in writing systems
The double ⟨aa⟩ sequence does not occur in native English words, but is found in some words derived from foreign languages such as Aaron and aardvark. However, ⟨a⟩ occurs in many common digraphs, all with their own sound or sounds, particularly ⟨ai⟩, ⟨au⟩, ⟨aw⟩, ⟨ay⟩, ⟨ea⟩ and ⟨oa⟩.
A
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Use in writing systems
⟨a⟩ is the third-most-commonly used letter in English (after ⟨e⟩ and ⟨t⟩) and French, the second most common in Spanish, and the most common in Portuguese. About 8.167% of letters used in English texts tend to be ⟨a⟩; the number is around 7.636% in French, 11.525% in Spanish, and 14.634% for Portuguese.
A
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Use in writing systems
In most languages that use the Latin alphabet, ⟨a⟩ denotes an open unrounded vowel, such as /a/, /ä/, or /ɑ/. An exception is Saanich, in which ⟨a⟩ (and the glyph Á) stands for a close-mid front unrounded vowel /e/.
A
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Use in writing systems
In phonetic and phonemic notation:
A
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Other uses
In algebra, the letter a along with various other letters of the alphabet is often used to denote a variable, with various conventional meanings in different areas of mathematics. Moreover, in 1637, René Descartes "invented the convention of representing unknowns in equations by x, y, and z, and knowns by a, b, and c", and this convention is still often followed, especially in elementary algebra.
A
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Other uses
In geometry, capital A, B, C etc. are used to denote segments, lines, rays, etc. A capital A is also typically used as one of the letters to represent an angle in a triangle, the lowercase a representing the side opposite angle A.
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Other uses
"A" is often used to denote something or someone of a better or more prestigious quality or status: A−, A or A+, the best grade that can be assigned by teachers for students' schoolwork; "A grade" for clean restaurants; A-list celebrities, etc. Such associations can have a motivating effect, as exposure to the letter A has been found to improve performance, when compared with other letters.
A
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Other uses
"A" is used as a prefix on some words, such as asymmetry, to mean "not" or "without" (from Greek).
A
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Other uses
In English grammar, "a", and its variant "an", is an indefinite article, used to introduce noun phrases.
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Other uses
Finally, the letter A is used to denote size, as in a narrow size shoe, or a small cup size in a brassiere.
A
290
Code points
These are the code points for the forms of the letter in various systems
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Use as a number
In the hexadecimal (base 16) numbering system, A is a number that corresponds to the number 10 in decimal (base 10) counting.
Alabama
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Alabama (/ˌæləˈbæmə/) is a state in the Southeastern region of the United States, bordered by Tennessee to the north; Georgia to the east; Florida and the Gulf of Mexico to the south; and Mississippi to the west. Alabama is the 30th largest by area and the 24th-most populous of the U.S. states.
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Alabama is nicknamed the Yellowhammer State, after the state bird. Alabama is also known as the "Heart of Dixie" and the "Cotton State". The state tree is the longleaf pine, and the state flower is the camellia. Alabama's capital is Montgomery, and its largest city by population and area is Huntsville. Its oldest city is Mobile, founded by French colonists (Alabama Creoles) in 1702 as the capital of French Louisiana. Greater Birmingham is Alabama's largest metropolitan area and its economic center.
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Originally home to many native tribes, present-day Alabama was a Spanish territory beginning in the sixteenth century until the French acquired it in the early eighteenth century. The British won the territory in 1763 until losing it in the American Revolutionary War. Spain held Mobile as part of Spanish West Florida until 1813. In December 1819, Alabama was recognized as a state. During the antebellum period, Alabama was a major producer of cotton, and widely used African American slave labor. In 1861, the state seceded from the United States to become part of the Confederate States of America, with Montgomery acting as its first capital, and rejoined the Union in 1868. Following the American Civil War, Alabama would suffer decades of economic hardship, in part due to agriculture and a few cash crops being the main driver of the state's economy. Similar to other former slave states, Alabamian legislators employed Jim Crow laws from the late 19th century up until the 1960s. High-profile events such as the Selma to Montgomery march made the state a major focal point of the civil rights movement in the 1950s and 1960s.
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During and after World War II, Alabama grew as the state's economy diversified with new industries. NASA's Marshall Space Flight Center in Huntsville would help Alabama's economic growth in the mid-to-late 20th century, by developing an aerospace industry. Alabama's economy in the 21st century is based on automotive, finance, tourism, manufacturing, aerospace, mineral extraction, healthcare, education, retail, and technology.
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The state's geography is diverse, with the north dominated by the mountainous Tennessee Valley and the south by Mobile Bay, a historically significant port. Politically, as part of the Deep South, Alabama is predominantly a conservative state, and is known for its Southern culture. Within Alabama, American football, particularly at the college level, plays a major part of the state's culture.
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Etymology
The European-American naming of the Alabama River and state was derived from the Alabama people, a Muskogean-speaking tribe whose members lived just below the confluence of the Coosa and Tallapoosa rivers on the upper reaches of the river. In the Alabama language, the word for a person of Alabama lineage is Albaamo (or variously Albaama or Albàamo in different dialects; the plural form is Albaamaha). The word's spelling varies significantly among historical sources. The first usage appears in three accounts of the Hernando de Soto expedition of 1540: Garcilaso de la Vega used Alibamo, while the Knight of Elvas and Rodrigo Ranjel wrote Alibamu and Limamu, respectively, in transliterations of the term. As early as 1702, the French called the tribe the Alibamon, with French maps identifying the river as Rivière des Alibamons. Other spellings of the name have included Alibamu, Alabamo, Albama, Alebamon, Alibama, Alibamou, Alabamu, and Allibamou. The use of state names derived from Native American languages is common in the U.S.; an estimated 26 states have names of Native American origin.
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Etymology
Sources disagree on the word's meaning. Some scholars suggest the word comes from the Choctaw alba (meaning 'plants' or 'weeds') and amo (meaning 'to cut', 'to trim', or 'to gather'). The meaning may have been 'clearers of the thicket' or 'herb gatherers', referring to clearing land for cultivation or collecting medicinal plants. The state has numerous place names of Native American origin.
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Etymology
An 1842 article in the Jacksonville Republican proposed it meant 'Here We Rest'. This notion was popularized in the 1850s through the writings of Alexander Beaufort Meek. Experts in the Muskogean languages have not found any evidence to support such a translation.
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History
Indigenous peoples of varying cultures lived in the area for thousands of years before the advent of European colonization. Trade with the northeastern tribes by the Ohio River began during the Burial Mound Period (1000 BCE – 700 CE) and continued until European contact.
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History
The agrarian Mississippian culture covered most of the state from 1000 to 1600 CE, with one of its major centers built at what is now the Moundville Archaeological Site in Moundville, Alabama. This is the second-largest complex of the classic Middle Mississippian era, after Cahokia in present-day Illinois, which was the center of the culture. Analysis of artifacts from archaeological excavations at Moundville were the basis of scholars' formulating the characteristics of the Southeastern Ceremonial Complex (SECC). Contrary to popular belief, the SECC appears to have no direct links to Mesoamerican culture but developed independently. The Ceremonial Complex represents a major component of the religion of the Mississippian peoples; it is one of the primary means by which their religion is understood.
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History
Among the historical tribes of Native American people living in present-day Alabama at the time of European contact were the Cherokee, an Iroquoian language people; and the Muskogean-speaking Alabama (Alibamu), Chickasaw, Choctaw, Creek, and Koasati. While part of the same large language family, the Muskogee tribes developed distinct cultures and languages.
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History
The Spanish were the first Europeans to reach Alabama during their exploration of North America in the 16th century. The expedition of Hernando de Soto passed through Mabila and other parts of the state in 1540. More than 160 years later, the French founded the region's first European settlement at Old Mobile in 1702. The city was moved to the current site of Mobile in 1711. This area was claimed by the French from 1702 to 1763 as part of La Louisiane.
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History
After the French lost to the British in the Seven Years' War, it became part of British West Florida from 1763 to 1783. After the United States victory in the American Revolutionary War, the territory was divided between the United States and Spain. The latter retained control of this western territory from 1783 until the surrender of the Spanish garrison at Mobile to U.S. forces on April 13, 1813.
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History
Thomas Bassett, a loyalist to the British monarchy during the Revolutionary era, was one of the earliest white settlers in the state outside Mobile. He settled in the Tombigbee District during the early 1770s. The district's boundaries were roughly limited to the area within a few miles of the Tombigbee River and included portions of what is today southern Clarke County, northernmost Mobile County, and most of Washington County.
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History
What is now the counties of Baldwin and Mobile became part of Spanish West Florida in 1783, part of the independent Republic of West Florida in 1810, and was finally added to the Mississippi Territory in 1812. Most of what is now the northern two-thirds of Alabama was known as the Yazoo lands beginning during the British colonial period. It was claimed by the Province of Georgia from 1767 onwards. Following the Revolutionary War, it remained a part of Georgia, although heavily disputed.
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History
With the exception of the area around Mobile and the Yazoo lands, what is now the lower one-third of Alabama was made part of the Mississippi Territory when it was organized in 1798. The Yazoo lands were added to the territory in 1804, following the Yazoo land scandal. Spain kept a claim on its former Spanish West Florida territory in what would become the coastal counties until the Adams–Onís Treaty officially ceded it to the United States in 1819.
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History
Before Mississippi's admission to statehood on December 10, 1817, the more sparsely settled eastern half of the territory was separated and named the Alabama Territory. The United States Congress created the Alabama Territory on March 3, 1817. St. Stephens, now abandoned, served as the territorial capital from 1817 to 1819.
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History
Alabama was admitted as the 22nd state on December 14, 1819, with Congress selecting Huntsville as the site for the first Constitutional Convention. From July 5 to August 2, 1819, delegates met to prepare the new state constitution. Huntsville served as temporary capital from 1819 to 1820, when the seat of government moved to Cahaba in Dallas County.
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History
Cahaba, now a ghost town, was the first permanent state capital from 1820 to 1825. The Alabama Fever land rush was underway when the state was admitted to the Union, with settlers and land speculators pouring into the state to take advantage of fertile land suitable for cotton cultivation. Part of the frontier in the 1820s and 1830s, its constitution provided for universal suffrage for white men.
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History
Southeastern planters and traders from the Upper South brought slaves with them as the cotton plantations in Alabama expanded. The economy of the central Black Belt (named for its dark, productive soil) was built around large cotton plantations whose owners' wealth grew mainly from slave labor. The area also drew many poor, disenfranchised people who became subsistence farmers. Alabama had an estimated population of under 10,000 people in 1810, but it increased to more than 300,000 people by 1830. Most Native American tribes were completely removed from the state within a few years of the passage of the Indian Removal Act by Congress in 1830.
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History
From 1826 to 1846, Tuscaloosa served as Alabama's capital. On January 30, 1846, the Alabama legislature announced it had voted to move the capital city from Tuscaloosa to Montgomery. The first legislative session in the new capital met in December 1847. A new capitol building was erected under the direction of Stephen Decatur Button of Philadelphia. The first structure burned down in 1849, but was rebuilt on the same site in 1851. This second capitol building in Montgomery remains to the present day. It was designed by Barachias Holt of Exeter, Maine.
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History
By 1860, the population had increased to 964,201 people, of which nearly half, 435,080, were enslaved African Americans, and 2,690 were free people of color. On January 11, 1861, Alabama declared its secession from the Union. After remaining an independent republic for a few days, it joined the Confederate States of America. The Confederacy's capital was initially at Montgomery. Alabama was heavily involved in the American Civil War. Although comparatively few battles were fought in the state, Alabama contributed about 120,000 soldiers to the war effort.
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History
A company of cavalry soldiers from Huntsville, Alabama, joined Nathan Bedford Forrest's battalion in Hopkinsville, Kentucky. The company wore new uniforms with yellow trim on the sleeves, collar and coattails. This led to them being greeted with "Yellowhammer", and the name later was applied to all Alabama troops in the Confederate Army.
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History
Alabama's slaves were freed by the 13th Amendment in 1865. Alabama was under military rule from the end of the war in May 1865 until its official restoration to the Union in 1868. From 1867 to 1874, with most white citizens barred temporarily from voting and freedmen enfranchised, many African Americans emerged as political leaders in the state. Alabama was represented in Congress during this period by three African-American congressmen: Jeremiah Haralson, Benjamin S. Turner, and James T. Rapier.
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History
Following the war, the state remained chiefly agricultural, with an economy tied to cotton. During Reconstruction, state legislators ratified a new state constitution in 1868 which created the state's first public school system and expanded women's rights. Legislators funded numerous public road and railroad projects, although these were plagued with allegations of fraud and misappropriation. Organized insurgent, resistance groups tried to suppress the freedmen and Republicans. Besides the short-lived original Ku Klux Klan, these included the Pale Faces, Knights of the White Camellia, Red Shirts, and the White League.
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History
Reconstruction in Alabama ended in 1874, when the Democrats regained control of the legislature and governor's office through an election dominated by fraud and violence. They wrote another constitution in 1875, and the legislature passed the Blaine Amendment, prohibiting public money from being used to finance religious-affiliated schools. The same year, legislation was approved that called for racially segregated schools. Railroad passenger cars were segregated in 1891.
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History
The new 1901 Constitution of Alabama included provisions for voter registration that effectively disenfranchised large portions of the population, including nearly all African Americans and Native Americans, and tens of thousands of poor European Americans, through making voter registration difficult, requiring a poll tax and literacy test. The 1901 constitution required racial segregation of public schools. By 1903 only 2,980 African Americans were registered in Alabama, although at least 74,000 were literate. This compared to more than 181,000 African Americans eligible to vote in 1900. The numbers dropped even more in later decades. The state legislature passed additional racial segregation laws related to public facilities into the 1950s: jails were segregated in 1911; hospitals in 1915; toilets, hotels, and restaurants in 1928; and bus stop waiting rooms in 1945.
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History
While the planter class had persuaded poor whites to vote for this legislative effort to suppress black voting, the new restrictions resulted in their disenfranchisement as well, due mostly to the imposition of a cumulative poll tax. By 1941, whites constituted a slight majority of those disenfranchised by these laws: 600,000 whites vs. 520,000 African Americans. Nearly all Blacks had lost the ability to vote. Despite numerous legal challenges which succeeded in overturning certain provisions, the state legislature would create new ones to maintain disenfranchisement. The exclusion of blacks from the political system persisted until after passage of federal civil rights legislation in 1965 to enforce their constitutional rights as citizens.
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History
The rural-dominated Alabama legislature consistently underfunded schools and services for the disenfranchised African Americans, but it did not relieve them of paying taxes. Partially as a response to chronic underfunding of education for African Americans in the South, the Rosenwald Fund began funding the construction of what came to be known as Rosenwald Schools. In Alabama, these schools were designed, and the construction partially financed with Rosenwald funds, which paid one-third of the construction costs. The fund required the local community and state to raise matching funds to pay the rest. Black residents effectively taxed themselves twice, by raising additional monies to supply matching funds for such schools, which were built in many rural areas. They often donated land and labor as well.
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History
Beginning in 1913, the first 80 Rosenwald Schools were built in Alabama for African American children. A total of 387 schools, seven teachers' houses, and several vocational buildings were completed by 1937 in the state. Several of the surviving school buildings in the state are now listed on the National Register of Historic Places.
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History
Continued racial discrimination and lynchings, agricultural depression, and the failure of the cotton crops due to boll weevil infestation led tens of thousands of African Americans from rural Alabama and other states to seek opportunities in northern and midwestern cities during the early decades of the 20th century as part of the Great Migration out of the South. Reflecting this emigration, the population growth rate in Alabama (see "historical populations" table below) dropped by nearly half from 1910 to 1920.
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History
At the same time, many rural people migrated to the city of Birmingham to work in new industrial jobs. Birmingham experienced such rapid growth it was called the "Magic City". By 1920, Birmingham was the 36th-largest city in the United States. Heavy industry and mining were the basis of its economy. Its residents were under-represented for decades in the state legislature, which refused to redistrict after each decennial census according to population changes, as it was required by the state constitution. This did not change until the late 1960s following a lawsuit and court order.
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History
Beginning in the 1940s, when the courts started taking the first steps to recognize the voting rights of black voters, the Alabama legislature took several counter-steps designed to disfranchise black voters. The legislature passed, and the voters ratified [as these were mostly white voters], a state constitutional amendment that gave local registrars greater latitude to disqualify voter registration applicants. Black citizens in Mobile successfully challenged this amendment as a violation of the Fifteenth Amendment. The legislature also changed the boundaries of Tuskegee to a 28-sided figure designed to fence out blacks from the city limits. The Supreme Court unanimously held that this racial "gerrymandering" violated the Constitution. In 1961, ... the Alabama legislature also intentionally diluted the effect of the black vote by instituting numbered place requirements for local elections.
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History
Industrial development related to the demands of World War II brought a level of prosperity to the state not seen since before the civil war. Rural workers poured into the largest cities in the state for better jobs and a higher standard of living. One example of this massive influx of workers occurred in Mobile. Between 1940 and 1943, more than 89,000 people moved into the city to work for war-related industries. Cotton and other cash crops faded in importance as the state developed a manufacturing and service base.
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History
Despite massive population changes in the state from 1901 to 1961, the rural-dominated legislature refused to reapportion House and Senate seats based on population, as required by the state constitution to follow the results of decennial censuses. They held on to old representation to maintain political and economic power in agricultural areas. One result was that Jefferson County, containing Birmingham's industrial and economic powerhouse, contributed more than one-third of all tax revenue to the state, but did not receive a proportional amount in services. Urban interests were consistently underrepresented in the legislature. A 1960 study noted that because of rural domination, "a minority of about 25% of the total state population is in majority control of the Alabama legislature."
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History
In the United States Supreme Court cases of Baker v. Carr (1962) and Reynolds v. Sims (1964), the court ruled that the principle of "one man, one vote" needed to be the basis of both houses of state legislatures, and that their districts had to be based on population rather than geographic counties.
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History
African Americans continued to press in the 1950s and 1960s to end disenfranchisement and segregation in the state through the civil rights movement, including legal challenges. In 1954, the U.S. Supreme Court ruled in Brown v. Board of Education that public schools had to be desegregated, but Alabama was slow to comply. During the 1960s, under Governor George Wallace, Alabama resisted compliance with federal demands for desegregation. The civil rights movement had notable events in Alabama, including the Montgomery bus boycott (1955–1956), Freedom Rides in 1961, and 1965 Selma to Montgomery marches. These contributed to Congressional passage and enactment of the Civil Rights Act of 1964 and Voting Rights Act of 1965 by the U.S. Congress.
Alabama
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History
Legal segregation ended in the states in 1964, but Jim Crow customs often continued until specifically challenged in court. According to The New York Times, by 2017, many of Alabama's African Americans were living in Alabama's cities such as Birmingham and Montgomery. Also, the Black Belt region across central Alabama "is home to largely poor counties that are predominantly African-American. These counties include Dallas, Lowndes, Marengo and Perry."
Alabama
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History
In 1972, for the first time since 1901, the legislature completed the congressional redistricting based on the decennial census. This benefited the urban areas that had developed, as well as all in the population who had been underrepresented for more than sixty years. Other changes were made to implement representative state house and senate districts.
Alabama
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History
Alabama has made some changes since the late 20th century and has used new types of voting to increase representation. In the 1980s, an omnibus redistricting case, Dillard v. Crenshaw County, challenged the at-large voting for representative seats of 180 Alabama jurisdictions, including counties and school boards. At-large voting had diluted the votes of any minority in a county, as the majority tended to take all seats. Despite African Americans making up a significant minority in the state, they had been unable to elect any representatives in most of the at-large jurisdictions.
Alabama
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History
As part of settlement of this case, five Alabama cities and counties, including Chilton County, adopted a system of cumulative voting for election of representatives in multi-seat jurisdictions. This has resulted in more proportional representation for voters. In another form of proportional representation, 23 jurisdictions use limited voting, as in Conecuh County. In 1982, limited voting was first tested in Conecuh County. Together use of these systems has increased the number of African Americans and women being elected to local offices, resulting in governments that are more representative of their citizens.
Alabama
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History
Beginning in the 1960s, the state's economy shifted away from its traditional lumber, steel, and textile industries because of increased foreign competition. Steel jobs, for instance, declined from 46,314 in 1950 to 14,185 in 2011. However, the state, particularly Huntsville, benefited from the opening of the George C. Marshall Space Flight Center in 1960, a major facility in the development of the Saturn rocket program and the space shuttle. Technology and manufacturing industries, such as automobile assembly, replaced some the state's older industries in the late twentieth century, but the state's economy and growth lagged behind other states in the area, such as Georgia and Florida.
Alabama
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History
In 2001, Alabama Supreme Court chief justice Roy Moore installed a statue of the Ten Commandments in the capitol in Montgomery. In 2002, the 11th US Circuit Court ordered the statue removed, but Moore refused to follow the court order, which led to protests around the capitol in favor of keeping the monument. The monument was removed in August 2003.
Alabama
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History
A few natural disasters have occurred in the state in the twenty-first century. In 2004, Hurricane Ivan, a category 3 storm upon landfall, struck the state and caused over $18 billion of damage. It was among the most destructive storms to strike the state in its modern history. A super outbreak of 62 tornadoes hit the state in April 2011 and killed 238 people, devastating many communities.
Alabama
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Geography
Alabama is the thirtieth-largest state in the United States with 52,419 square miles (135,760 km) of total area: 3.2% of the area is water, making Alabama 23rd in the amount of surface water, also giving it the second-largest inland waterway system in the United States. About three-fifths of the land area is part of the Gulf Coastal Plain, a gentle plain with a general descent towards the Mississippi River and the Gulf of Mexico. The North Alabama region is mostly mountainous, with the Tennessee River cutting a large valley and creating numerous creeks, streams, rivers, mountains, and lakes.
Alabama
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Geography
Alabama is bordered by the states of Tennessee to the north, Georgia to the east, Florida to the south, and Mississippi to the west. Alabama has coastline at the Gulf of Mexico, in the extreme southern edge of the state. The state ranges in elevation from sea level at Mobile Bay to more than 2,000 feet (610 m) in the northeast, to Mount Cheaha at 2,413 ft (735 m).
Alabama
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Geography
Alabama's land consists of 22 million acres (89,000 km) of forest or 67% of the state's total land area. Suburban Baldwin County, along the Gulf Coast, is the largest county in the state in both land area and water area.
Alabama
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Geography
Areas in Alabama administered by the National Park Service include Horseshoe Bend National Military Park near Alexander City; Little River Canyon National Preserve near Fort Payne; Russell Cave National Monument in Bridgeport; Tuskegee Airmen National Historic Site in Tuskegee; and Tuskegee Institute National Historic Site near Tuskegee. Additionally, Alabama has four National Forests: Conecuh, Talladega, Tuskegee, and William B. Bankhead. Alabama also contains the Natchez Trace Parkway, the Selma To Montgomery National Historic Trail, and the Trail of Tears National Historic Trail.
Alabama
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Geography
Notable natural wonders include: the "Natural Bridge" rock, the longest natural bridge east of the Rockies, located just south of Haleyville; Cathedral Caverns in Marshall County, named for its cathedral-like appearance, features one of the largest cave entrances and stalagmites in the world; Ecor Rouge in Fairhope, the highest coastline point between Maine and Mexico; DeSoto Caverns in Childersburg, the first officially recorded cave in the United States; Noccalula Falls in Gadsden features a 90-foot waterfall; Dismals Canyon near Phil Campbell, home to two waterfalls, six natural bridges and allegedly served as a hideout for legendary outlaw Jesse James; Stephens Gap Cave in Jackson County boasts a 143-foot pit, two waterfalls and is one of the most photographed wild cave scenes in America; Little River Canyon near Fort Payne, one of the nation's longest mountaintop rivers; Rickwood Caverns near Warrior features an underground pool, blind cave fish and 260-million-year-old limestone formations; and the Walls of Jericho canyon on the Alabama-Tennessee state line.
Alabama
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Geography
A 5-mile (8 km)-wide meteorite impact crater is located in Elmore County, just north of Montgomery. This is the Wetumpka crater, the site of "Alabama's greatest natural disaster". A 1,000-foot (300 m)-wide meteorite hit the area about 80 million years ago. The hills just east of downtown Wetumpka showcase the eroded remains of the impact crater that was blasted into the bedrock, with the area labeled the Wetumpka crater or astrobleme ("star-wound") because of the concentric rings of fractures and zones of shattered rock that can be found beneath the surface. In 2002, Christian Koeberl with the Institute of Geochemistry University of Vienna published evidence and established the site as the 157th recognized impact crater on Earth.
Alabama
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Geography
The state is classified as humid subtropical (Cfa) under the Koppen Climate Classification. The average annual temperature is 64 °F (18 °C). Temperatures tend to be warmer in the southern part of the state with its proximity to the Gulf of Mexico, while the northern parts of the state, especially in the Appalachian Mountains in the northeast, tend to be slightly cooler. Generally, Alabama has very hot summers and mild winters with copious precipitation throughout the year. Alabama receives an average of 56 inches (1,400 mm) of rainfall annually and enjoys a lengthy growing season of up to 300 days in the southern part of the state.
Alabama
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Geography
Summers in Alabama are among the hottest in the U.S., with high temperatures averaging over 90 °F (32 °C) throughout the summer in some parts of the state. Alabama is also prone to tropical storms and hurricanes. Areas of the state far away from the Gulf are not immune to the effects of the storms, which often dump tremendous amounts of rain as they move inland and weaken.
Alabama
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Geography
South Alabama reports many thunderstorms. The Gulf Coast, around Mobile Bay, averages between 70 and 80 days per year with thunder reported. This activity decreases somewhat further north in the state, but even the far north of the state reports thunder on about 60 days per year. Occasionally, thunderstorms are severe with frequent lightning and large hail; the central and northern parts of the state are most vulnerable to this type of storm. Alabama ranks ninth in the number of deaths from lightning and tenth in the number of deaths from lightning strikes per capita.
Alabama
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Geography
Alabama, along with Oklahoma and Iowa, has the most confirmed F5 and EF5 tornadoes of any state, according to statistics from the National Climatic Data Center for the period January 1, 1950, to June 2013. Several long-tracked F5/EF5 tornadoes have contributed to Alabama reporting more tornado fatalities since 1950 than any other state. The state was affected by the 1974 Super Outbreak and was devastated tremendously by the 2011 Super Outbreak. The 2011 Super Outbreak produced a record amount of tornadoes in the state. The tally reached 62.
Alabama
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Geography
The peak season for tornadoes varies from the northern to southern parts of the state. Alabama is one of the few places in the world that has a secondary tornado season in November and December besides the typically severe spring. The northern part—along the Tennessee River Valley—is most vulnerable. The area of Alabama and Mississippi most affected by tornadoes is sometimes referred to as Dixie Alley, as distinct from the Tornado Alley of the Southern Plains.
Alabama
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Geography
Winters are generally mild in Alabama, as they are throughout most of the Southeastern United States, with average January low temperatures around 40 °F (4 °C) in Mobile and around 32 °F (0 °C) in Birmingham. Although snow is a rare event in much of Alabama, areas of the state north of Montgomery may receive a dusting of snow a few times every winter, with an occasional moderately heavy snowfall every few years. Historic snowfall events include New Year's Eve 1963 snowstorm and the 1993 Storm of the Century. The annual average snowfall for the Birmingham area is 2 inches (51 mm) per year. In the southern Gulf coast, snowfall is less frequent, sometimes going several years without any snowfall.
Alabama
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Geography
Alabama's highest temperature of 112 °F (44 °C) was recorded on September 5, 1925, in the unincorporated community of Centerville. The record low of −27 °F (−33 °C) occurred on January 30, 1966, in New Market.
Alabama
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Geography
Alabama is home to a diverse array of flora and fauna in habitats that range from the Tennessee Valley, Appalachian Plateau, and Ridge-and-Valley Appalachians of the north to the Piedmont, Canebrake, and Black Belt of the central region to the Gulf Coastal Plain and beaches along the Gulf of Mexico in the south. The state is usually ranked among the top in nation for its range of overall biodiversity.
Alabama
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Geography
Alabama is in the subtropical coniferous forest biome and once boasted huge expanses of pine forest, which still form the largest proportion of forests in the state. It currently ranks fifth in the nation for the diversity of its flora. It is home to nearly 4,000 pteridophyte and spermatophyte plant species.
Alabama
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Geography
Indigenous animal species in the state include 62 mammal species, 93 reptile species, 73 amphibian species, roughly 307 native freshwater fish species, and 420 bird species that spend at least part of their year within the state. Invertebrates include 97 crayfish species and 383 mollusk species. 113 of these mollusk species have never been collected outside the state.