dancinlab/anima-corpus-5lang-unified huggingface dataset:
Just as fresh snow has a higher albedo than does dirty snow, the albedo of snow-covered sea ice is far higher than that of sea water. Sea water absorbs more solar radiation than would the same surface covered with reflective snow. When sea ice melts, either due to a rise in sea temperature or in response to increased solar radiation from above, the snow-covered surface is reduced, and more surface of sea water is exposed, so the rate of energy absorption increases. The extra absorbed energy heats the sea water, which in turn increases the rate at which sea ice melts. As with the preceding example of snowmelt, the process of melting of sea ice is thus another example of a positive feedback. Both positive feedback loops have long been recognized as important for global warming.
Solar photovoltaic effects 
Albedo can affect the electrical energy output of solar photovoltaic devices. For example, the effects of a spectrally responsive albedo are illustrated by the differences between the spectrally weighted albedo of solar photovoltaic technology based on hydrogenated amorphous silicon (a-Si:H) and crystalline silicon (c-Si)-based compared to traditional spectral-integrated albedo predictions. Research showed impacts of over 10% for vertically (90°) mounted systems, but such effects were substantially lower for systems with lower surface tilts. Spectral albedo strongly affects the performance of bifacial solar cells where rear surface performance gains of over 20% have been observed for c-Si cells installed above healthy vegetation. An analysis on the bias due to the specular reflectivity of 22 commonly occurring surface materials (both human-made and natural) provided effective albedo values for simulating the performance of seven photovoltaic materials mounted on three common photovoltaic system topologies: industrial (solar farms), commercial flat rooftops and residential pitched-roof applications.
In the case of evergreen forests with seasonal snow cover albedo reduction may be great enough for deforestation to cause a net cooling effect. Trees also impact climate in extremely complicated ways through evapotranspiration. The water vapor causes cooling on the land surface, causes heating where it condenses, acts a strong greenhouse gas, and can increase albedo when it condenses into clouds. Scientists generally treat evapotranspiration as a net cooling impact, and the net climate impact of albedo and evapotranspiration changes from deforestation depends greatly on local climate.
In seasonally snow-covered zones, winter albedos of treeless areas are 10% to 50% higher than nearby forested areas because snow does not cover the trees as readily. Deciduous trees have an albedo value of about 0.15 to 0.18 whereas coniferous trees have a value of about 0.09 to 0.15. Variation in summer albedo across both forest types is associated with maximum rates of photosynthesis because plants with high growth capacity display a greater fraction of their foliage for direct interception of incoming radiation in the upper canopy. The result is that wavelengths of light not used in photosynthesis are more likely to be reflected back to space rather than being absorbed by other surfaces lower in the canopy.
Although the reflectivity of water is very low at low and medium angles of incident light, it becomes very high at high angles of incident light such as those that occur on the illuminated side of Earth near the terminator (early morning, late afternoon, and near the poles). However, as mentioned above, waviness causes an appreciable reduction. Because light specularly reflected from water does not usually reach the viewer, water is usually considered to have a very low albedo in spite of its high reflectivity at high angles of incident light.
Aerosol 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:
 Aerosol direct effect. Aerosols directly scatter and absorb radiation. The scattering of radiation causes atmospheric cooling, whereas absorption can cause atmospheric warming.
 Aerosol indirect effect. Aerosols modify the properties of clouds through a subset of the aerosol population called cloud condensation nuclei. Increased nuclei concentrations lead to increased cloud droplet number concentrations, which in turn leads to increased cloud albedo, increased light scattering and radiative cooling (first indirect effect), but also leads to reduced precipitation efficiency and increased lifetime of the cloud (second indirect effect).
Black carbon
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−2, with a range +0.1 to +0.4 W m−2. 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.
Optical or visual 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.
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.
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.
Radar 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, , , or  (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.
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 ), 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.
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.
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 , 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.
Typographic variants 
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.
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.
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.
Use in writing systems
English 
In modern English orthography, the letter  represents at least seven different vowel sounds:
the near-open front unrounded vowel  as in pad;
the open back unrounded vowel  as in father, which is closer to its original Latin and Greek sound;
the diphthong  as in ace and major (usually when  is followed by one, or occasionally two, consonants and then another vowel letter) – this results from Middle English lengthening followed by the Great Vowel Shift;
the modified form of the above sound that occurs before , as in square and Mary;
the rounded vowel of water;
the shorter rounded vowel (not present in General American) in was and what;
a schwa, in many unstressed syllables, as in about, comma, solar.
Related characters
Descendants and related characters in the Latin alphabet 
Æ æ : Latin AE ligature
A with diacritics: Å å Ǻ ǻ Ḁ ḁ ẚ Ă ă Ặ ặ Ắ ắ Ằ ằ Ẳ ẳ Ẵ ẵ Ȃ ȃ Â â Ậ ậ Ấ ấ Ầ ầ Ẫ ẫ Ẩ ẩ Ả ả Ǎ ǎ Ⱥ ⱥ Ȧ ȧ Ǡ ǡ Ạ ạ Ä ä Ǟ ǟ À à Ȁ ȁ Á á Ā ā Ā̀ ā̀ Ã ã Ą ą Ą́ ą́ Ą̃ ą̃ A̲ a̲ ᶏ
Phonetic alphabet symbols related to A (the International Phonetic Alphabet only uses lowercase, but uppercase forms are used in some other writing systems): 
Ɑ ɑ : Latin letter alpha / script A, which represents an open back unrounded vowel in the IPA
ᶐ : Latin small letter alpha with retroflex hook
Ɐ ɐ : Turned A, which represents a near-open central vowel in the IPA
Λ ʌ : Turned V (also called a wedge, a caret, or a hat), which represents an open-mid back unrounded vowel in the IPA
Ɒ ɒ : Turned alpha / script A, which represents an open back rounded vowel in the IPA
ᶛ : Modifier letter small turned alpha
ᴀ : Small capital A, an obsolete or non-standard symbol in the International Phonetic Alphabet used to represent various sounds (mainly open vowels)
A a ᵄ : Modifier letters are used in the Uralic Phonetic Alphabet (UPA) (sometimes encoded with Unicode subscripts and superscripts)
a : Subscript small a is used in Indo-European studies
ꬱ : Small letter a reversed-schwa is used in the Teuthonista phonetic transcription system
Ꞻ ꞻ : Glottal A, used in the transliteration of Ugaritic
𐤀 : Semitic letter Aleph, from which the following symbols originally derive
Α α : Greek letter Alpha, from which the following letters derive
А а : Cyrillic letter A
 : Coptic letter Alpha
𐌀 : Old Italic A, which is the ancestor of modern Latin A
 : Runic letter ansuz, which probably derives from old Italic A
 : Gothic letter aza/asks
Ա ա : Armenian letter Ayb
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.
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.
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  (or variously  or  in different dialects; the plural form is ). 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 , 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 , with French maps identifying the river as . 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.
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.
European settlement 
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.
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.
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.
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.
Civil War and Reconstruction 
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.
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.
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.
20th century 
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.
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.
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.