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Thursday, October 5, 2023

Iron(III) oxide-hydroxide

From Wikipedia, the free encyclopedia
Iron(III) oxide-hydroxide
Samples of iron(III) oxide-hydroxide monohydrate in a vial, and a spoon
Names
IUPAC name
Iron(III) oxide-hydroxide
Other names
Metaferric acid
Ferric oxyhydroxide
Goethite

Iron(III) oxide-hydroxide or ferric oxyhydroxide is the chemical compound of iron, oxygen, and hydrogen with formula FeO(OH).

The compound is often encountered as one of its hydrates, FeO(OH)·nH
2
O
[rust]. The monohydrate FeO(OH)·H
2
O
is often referred to as iron(III) hydroxide Fe(OH)
3
, hydrated iron oxide, yellow iron oxide, or Pigment Yellow 42.

Natural occurrences

Minerals

Anhydrous ferric hydroxide occurs in the nature as the exceedingly rare mineral bernalite, Fe(OH)3·nH2O (n = 0.0–0.25). Iron oxyhydroxides, FeOOH, are much more common and occur naturally as structurally different minerals (polymorphs) denoted by the Greek letters α, β, γ and δ.

  • Goethite, α-FeO(OH), has been used as an ochre pigment since prehistoric times.
  • Akaganeite is the β polymorph, formed by weathering and noted for its presence in some meteorites and the lunar surface. However, recently it has been determined that it must contain some chloride ions to stabilize its structure, so that its more accurate formula is FeO
    0.833
    (OH)
    1.167
    Cl
    0.167
    or Fe
    6
    O
    5
    (OH)
    7
    Cl
    .
  • Lepidocrocite, the γ polymorph, is commonly encountered as rust on the inside of steel water pipes and tanks.
  • Feroxyhyte (δ) is formed under the high pressure conditions of sea and ocean floors, being thermodynamically unstable with respect to the α polymorph (goethite) at surface conditions.

Non-mineral

Goethite and lepidocrocite, both crystallizing in orthorhombic system, are the most common forms of iron(III) oxyhydroxide and the most important mineral carriers of iron in soils.

Mineraloids

Iron(III) oxyhydroxide is the main component of other minerals and mineraloids:

Properties

The color of iron(III) oxyhydroxide ranges from yellow through dark-brown to black, depending on the degree of hydration, particle size and shape, and crystal structure.

Structure

The crystal structure of β-FeOOH (akaganeite) is that of hollandite or BaMn
8
O
16
. The unit cell is tetragonal with a=1.048 and c=0.3023 nm, and contains eight formula units of FeOOH. Its dimensions are about 500 × 50 × 50 nm. Twinning often produces particles with the shape of hexagonal stars. 

Chemistry

On heating, β-FeOOH decomposes and recrystallizes as α-Fe
2
O
3
(hematite).

Uses

Limonite, a mixture of various hydrates and polymorphs of ferric oxyhydroxide, is one of the three major iron ores, having been used since at least 2500 BC.

Yellow iron oxide, or Pigment Yellow 42, is Food and Drug Administration (FDA) approved for use in cosmetics and is used in some tattoo inks.

Iron oxide-hydroxide is also used in aquarium water treatment as a phosphate binder.

Iron oxide-hydroxide nanoparticles have been studied as possible adsorbents for lead removal from aquatic media.

Medication

Iron polymaltose is used in treatment of iron-deficiency anemia.

Production

Iron(III) oxyhydroxide precipitates from solutions of iron(III) salts at pH between 6.5 and 8. Thus the oxyhydroxide can be obtained in the lab by reacting an iron(III) salt, such as ferric chloride or ferric nitrate, with sodium hydroxide:

FeCl
3
+ 3 NaOH → Fe(OH)
3
+ 3 NaCl
Fe(NO
3
)
3
+ 3 NaOH → Fe(OH)
3
+ 3 NaNO
3

In fact, when dissolved in water, pure FeCl
3
will hydrolyze to some extent, yielding the oxyhydroxide and making the solution acidic:

FeCl
3
+ 2 H
2
O
FeOOH + 3 HCl

Therefore, the compound can also be obtained by the decomposition of acidic solutions of iron(III) chloride held near the boiling point for days or weeks:

FeCl
3
+ 2 H
2
O
FeOOH(s) + 3 HCl(g)

(The same process applied to iron(III) nitrate Fe(NO
3
)
3
or perchlorate Fe(ClO
4
)
3
solutions yields instead particles of α-Fe
2
O
3
.)

Another similar route is the decomposition of iron(III) nitrate dissolved in stearic acid at about 120 °C.

The oxyhydroxide prepared from ferric chloride is usually the β polymorph (akaganeite), often in the form of thin needles.

The oxyhydroxide can also be produced by a solid-state transformation from iron(II) chloride tetrahydrate FeCl
2
·4H
2
O
.

The compound also readily forms when iron(II) hydroxide is exposed to air:

4Fe(OH)
2
+ O
2
→ 4 FeOOH + 2 H
2
O

The iron(II) hydroxide can also be oxidized by hydrogen peroxide in the presence of an acid:

2Fe(OH)
2
+ H
2
O
2
→ 2 Fe(OH)
3

Hoi polloi

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Hoi_polloi

Hoi polloi (/ˌhɔɪ pəˈlɔɪ/; from Ancient Greek οἱ πολλοί (hoi polloí) 'the many') is an expression from Greek that means "the many" or, in the strictest sense, "the people". In English, it has been given a negative connotation to signify the masses. Synonyms for hoi polloi include "the plebs" (plebeians), "the rabble", "the masses", "the great unwashed", "riffraff", and "the proles" (proletarians).

The phrase probably became known to English scholars through Pericles' Funeral Oration, as mentioned in Thucydides' History of the Peloponnesian War. Pericles uses it in a positive way when praising the Athenian democracy, contrasting it with hoi oligoi, "the few" (Greek: οἱ ὀλίγοι; see also oligarchy).

Its current English usage originated in the early 19th century, a time when it was generally accepted that one must be familiar with Greek and Latin in order to be considered well educated. The phrase was originally written in Greek letters. Knowledge of these languages served to set apart the speaker from hoi polloi in question, who were not similarly educated.

Pronunciation

Pronunciation depends on the speaker:

Usage

Some linguists argue that, given that hoi is a definite article, the phrase "the hoi polloi" is redundant, akin to saying "the the masses". Others argue that this is inconsistent with other English loanwords. The word "alcohol", for instance, derives from the Arabic al-kuhl, al being an article, yet "the alcohol" is universally accepted as good grammar.

Appearances in the nineteenth century

There have been numerous uses of the term in English literature. James Fenimore Cooper, author of The Last of the Mohicans, is often credited with making the first recorded usage of the term in English. The first recorded use by Cooper occurs in his 1837 work Gleanings in Europe where he writes "After which the oi polloi are enrolled as they can find interest."

Diagram of Lord Byron's view of the hoi polloi, as arranged in his journals, ranked as "the many" beneath a handful of his personal contacts

Lord Byron had, in fact, previously used the term in his letters and journal. In one journal entry, dated 24 November 1813, Byron writes:

I have not answered W. Scott's last letter,—but I will. I regret to hear from others, that he has lately been unfortunate in pecuniary involvements. He is undoubtedly the Monarch of Parnassus, and the most English of bards. I should place Rogers next in the living list (I value him more as the last of the best school) —Moore and Campbell both third—Southey and Wordsworth and Coleridge—the rest, οι πολλοί [hoi polloi in Greek].

Byron also wrote an 1821 entry in his journal "... one or two others, with myself, put on masks, and went on the stage with the 'oi polloi."

In Confessions of an English Opium-Eater, Thomas De Quincey uses the term during a passage discussing which of the English classes is most proud, noting "... the children of bishops carry about with them an austere and repulsive air, indicative of claims not generally acknowledged, a sort of noli me tangere manner, nervously apprehensive of too familiar approach, and shrinking with the sensitiveness of a gouty man from all contact with the οι πολλοι."

While Charles Darwin was at the University of Cambridge from 1828 to 1831, undergraduates used the term "hoi polloi" or "Poll" for those reading for an ordinary degree, the "pass degree". At that time only capable mathematicians would take the Tripos or honours degree. In his autobiography written in the 1870s, Darwin recalled that "By answering well the examination questions in Paley, by doing Euclid well, and by not failing miserably in Classics, I gained a good place among the οἱ πολλοί, or crowd of men who do not go in for honours."

W. S. Gilbert used the term in 1882 when he wrote the libretto of the comic opera Iolanthe. In Act I, the following exchange occurs between a group of disgruntled fairies who are arranging to elevate a lowly shepherd to the peerage, and members of the House of Lords who will not hear of such a thing:

PEERS: Our lordly style
You shall not quench
With base canaille!

FAIRIES: (That word is French.)

PEERS: Distinction ebbs
Before a herd
Of vulgar plebs!

FAIRIES: (A Latin word.)

PEERS: 'Twould fill with joy,
And madness stark
The hoi polloi!

FAIRIES: (A Greek remark.)

Gilbert's parallel use of canaille, plebs (plebeians), and hoi polloi makes it clear that the term is derogatory of the lower classes. In many versions of the vocal score, it is written as "οἱ πολλοί", likely confusing generations of amateur choristers who had not had the advantages of learning the Greek at some point of their lives.

John Dryden used the phrase in his Essay of Dramatick Poesie, published in 1668. Dryden spells the phrase with Greek letters, but the rest of the sentence is in English (and he does precede it with "the").

Appearances in the twentieth century

The term has appeared in several films and radio programs. For example, one of the earliest short films from the Three Stooges, Hoi Polloi (1935), opens in an exclusive restaurant where two wealthy gentlemen are arguing whether heredity or environment is more important in shaping character. They make a bet and pick on nearby trashmen (the Stooges) to prove their theory. At the conclusion of three months in training, the Stooges attend a dinner party, where they thoroughly embarrass the professors.

The University of Dayton's Don Morlan says, "The theme in these shorts of the Stooges against the rich is bringing the rich down to their level and shaking their heads." A typical Stooges joke from the film is when someone addresses them as "gentlemen", and they look over their shoulders to see who is being addressed. The Three Stooges turn the tables on their hosts by calling them "hoi polloi" at the end.

At the English public school (i.e., private school) Haileybury and Imperial Service College, in the 1950s and '60s, grammar schoolboys from nearby Hertford were referred to as "oips", from "hoi polloi", to distinguish them from comprehensive and secondary modern schoolboys, the lowest of the low, who were called "oiks".

Carole King's TV special Really Rosie (based on Maurice Sendak's works) contains a song called "My Simple Humble Neighborhood", in which Rosie remembers those whom she's met over the years. In the process, she mentions the hoi polloi as well as the grand elite.

The term continues to be used in contemporary writing. In his 1983 introduction to Robert Anton Wilson's Prometheus Rising, Israel Regardie writes, "Once I was even so presumptuous as to warn (Wilson) in a letter that his humor was much too good to waste on hoi polloi who generally speaking would not understand it and might even resent it."

The term "hoi polloi" was used in a dramatic scene in the film Dead Poets Society (1989). In this scene, Professor Keating speaks negatively about the use of the article "the" in front of the phrase:

Keating: This is battle, boys. War! Your souls are at a critical juncture. Either you will succumb to the hoi polloi and the fruit will die on the vine—or you will triumph as individuals. It may be a coincidence that part of my duties are to teach you about Romanticism, but let me assure you that I take the task quite seriously. You will learn what this school wants you to learn in my class, but if I do my job properly, you will also learn a great deal more. You will learn to savor language and words because they are the stepping stones to everything you might endeavor to do in life and do well. A moment ago I used the term 'hoi polloi.' Who knows what it means? Come on, Overstreet, you twirp. (laughter) Anderson, are you a man or a boil?

Anderson shakes his head "no", but Meeks raises his hands and speaks: "The hoi polloi. Doesn't it mean the herd?"

Keating: Precisely, Meeks. Greek for the herd. However, be warned that, when you say "the hoi polloi" you are actually saying "the the herd." Indicating that you too are "hoi polloi".

Keating's tone makes clear that he considers this statement to be an insult. He used the phrase "the hoi polloi", to demonstrate the mistake he warned against.

The term was also used in the comedy film Caddyshack (1980). In a rare moment of cleverness, Spaulding Smails greets Danny Noonan as he arrives for the christening of The Flying Wasp, the boat belonging to Judge Elihu Smails (Spaulding's grandfather), with "Ahoy, polloi! Where did you come from, a scotch ad?" This is particularly ironic, because Danny has just finished mowing the Judge's lawn, and arrives overdressed, wearing a sailboat captain's outfit (as the girl seated next to him points out, Danny "looks like Dick Cavett").

Todd Rundgren's band Utopia recorded a song titled "Hoi Polloi" on their album Deface the Music (1980), in which all of the songs are written and performed in the style of the Beatles.

The Lovin' Spoonful's song "Jug Band Music" includes the line: "He tried to mooch a towel from the hoi polloi."

In the song "Risingson" on Massive Attack's Mezzanine album, the singer apparently appeals to his company to leave the club they're in, deriding the common persons' infatuation with them, and implying that he's about to slide into antisocial behaviour:

Toy-like people make me boy-like (...)
And everything you got, hoi polloi like
Now you're lost and you're lethal
And now's about the time you gotta leave all

These good people...dream on.

In an episode of This American Life, radio host Ira Glass uses the term hoi polloi while relaying a story about a woman who believes the letter 'q' should occur later in the alphabet. He goes on to say that "Q does not belong in the middle of the alphabet where it is, with the hoi polloi of the alphabet, with your 'm' 'n' and 'p'. Letters that will just join any word for the asking."

The term was used in a first-series episode (The New Vicar, aired 5 November 1990) of the British sitcom Keeping Up Appearances. The main character, Hyacinth Bucket, gets into a telephone argument with a bakery employee. When the employee abruptly hangs up in frustration, Hyacinth disparagingly refers to him as "hoi polloi". This is in keeping with her character; she looks down upon those she considers to be of lesser social standing, including working-class people.

Hoi Polloi was used in Larry Marder's Tales of the Beanworld to name the unusual group of creatures that lived beneath the Beanworld.

In the first scene of The PlayStation ad "Double Life," a British man says, "In the day, I do my job, I ride the bus, Roll up my sleeves with the Hoi polloi".

Sue Townsend's Adrian Mole writes a poem called "The Hoi Polloi Reception" and later works as a cook "offal chef" in a Soho restaurant called Hoi Polloi.

The Scottish punk rock band Oi Polloi got their name as a pun of the Greek phrase.

Appearances in the twenty-first century

The August 14, 2001 episode of CNN's Larry King Live program included a discussion about whether the sport of polo was an appropriate part of the image of the British Royal Family. Joining King on the program were "best-selling biographer and veteran royal watcher Robert Lacey" and Kitty Kelley, author of the book The Royals. Their discussions focused on Prince Charles and his son Prince William:

Lacey said, "There is another risk that I see in polo. Polo is a very nouveau riche, I think, rather vulgar game. I can say that having played it myself, and I don't think it does Prince Charles's image, or, I dare say, this is probably arrogant of me, his spirit any good. I don't think it is a good thing for him to be involved in. I also, I'm afraid, don't think [polo] is a good thing for [Charles] to be encouraging his sons to get involved in. It is a very "playboy" set. We saw Harry recently all night clubbing, and why not, some might say, playing polo down in the south of Spain. I think the whole polo syndrome is something that the royal family would do very well to get uninvolved with as soon as possible.

King turned the question to Kelley, saying, "Kitty, it is kind of hoi polloi, although it is an incredible sport in which, I have been told, that the horse is 80 percent of the game, the rider 20 percent. But it is a great sport to watch. But it is hoi polloi isn't it?"

To which Kelley replied, "Yes, I do agree with Robert. The time is come and gone for the royals to be involved with polo. I mean it is – it just increases that dissipated aristo-image that they have, and it is too bad to encourage someone like Prince William to get involved."

The term appears in the 2003 Broadway musical Wicked, where it is used by the characters Elphaba and Glinda to refer to the many inhabitants of the Emerald City: "... I wanna be in this hoi polloi ..."

The term also appears in the 2007 film Hairspray, where it is used by the character Edna saying: "You see me hobnobbing and drinking Rum and Cokes with all those hoi polloi?"

Jack Cafferty, a CNN anchorman, was caught misusing the term. On 9 December 2004 he retracted his statement, saying "And hoi-polloi refers to common people, not those rich morons that are evicting those two red-tail hawks (ph) from that fifth Avenue co-op. I misused the word hoi-polloi. And for that I humbly apologize."

New media and new inventions have also been described as being by or for the hoi polloi. Bob Garfield, co-host of NPR's On the Media program, 8 November 2005, used the phrase in reference to changing practices in the media, especially Wikipedia, "The people in the encyclopedia business, I understand, tend to sniff at the wiki process as being the product of the mere hoi polloi."

In "Sunk Costs" (season 3 episode 3) of Better Call Saul, Jimmy has been arrested and the DDA (Oakley) teases him "getting fingerprinted with the hoi polloi".

In "Hooray! Todd Episode!" (season 4 episode 3) of BoJack Horseman, Princess Carolyn (in the hopes of making a celebrity actress more relatable to the public) orders a press release to be prepared, stating "Portnoy finds joy in hoi polloi boy toy", referring to Todd as a "down-to-earth boring nobody".

Cellar Darling uses the expression as the lyrical hook in the song The Hermit from their debut album This Is the Sound.

List of twenty-first century commercial uses

The phrase "hoi polloi" has been used to promote products and businesses. As described by the Pittsburgh Dish, the name "Hoi Polloi" may be chosen to indicate that the brand or service will appeal to the "common people".

  • Hoi Polloi is the name of many businesses, including a restaurant in the United Kingdom, Hoipolloi a theatre company based in Cambridge in the United Kingdom, a dance group based in New York City, a woman's boutique in New Orleans, Louisiana, a Cafe-Bar in Agia Galini, Greece, a film crew in the United Kingdom, and a global telecommunications company
  • Oi Polloi is a Scottish anarcho-punk group, whose name is a pun on the term, and also Oi! music. Hoi Polloi was an alternative gospel band from New Zealand
  • Oi Polloi is the name of a menswear boutique founded in Manchester, with stores in Manchester and London
  • Hoi Polloi is a Marketing Communications blog by Angelo Fernando, a business writer covering technology, marketing, and interactive media
  • Hoi Polloi is the title of a literary journal produced by Dog Days Press in Massachusetts
  • Ahoi Polloi is the name of a well-known German cartoon blog

The phrase has also been used in commercial works as the name a race of people

Asian Dust

From Wikipedia, the free encyclopedia
Yellow Dust (China Dust)
Dust clouds leaving mainland China and traveling toward Korea and Japan.
Chinese name
Traditional Chinese
Simplified Chinese
China dust soars in the arid regions of mainland China and rides on the wind to descend to regions such as Japan.

Asian Dust (also yellow dust, yellow sand, yellow wind or China dust storms) is a meteorological phenomenon that affects much of East Asia year-round and especially during the spring months. The dust originates in the deserts of China, Mongolia, and Kazakhstan, where high-speed surface winds and intense dust storms kick up dense clouds of fine, dry soil particles. These clouds are then carried eastward by prevailing winds and pass over China, North and South Korea, and Japan, as well as parts of the Russian Far East. Sometimes, the airborne particulates are carried much further, in significant concentrations which affect air quality as far east as the United States.

Since the turn of the 21st century, coinciding with the rapid industrialization of China, yellow dust has become a serious health problem due to the increase of industrial pollutants contained in the dust. Intensified desertification due to deforestation has been causing longer and more frequent occurrences. The issue has been exacerbated as the Aral Sea of Kazakhstan and Uzbekistan has largely dried up. This started in the 1960s with the diversion of the Amu River and Syr River, as part of a Soviet agricultural program to irrigate Central Asian deserts, mainly for cotton plantations.

Ancient reports

Some of the earliest written records of dust storm activity are recorded in ancient Chinese literature. It is believed that the earliest Chinese dust storm record was found in the Zhu Shu Ji Nian (Chinese: 竹书纪年; English: the Bamboo Annals). The record said: in the fifth year of Di Xin (1150 BC, Di Xin was the Era Name of the King Di Xin of Shang Dynasty), it rained dust at Bo (Bo is a place in Henan Province in China; in Classical Chinese: 帝辛五年,雨土于亳).

The first known record of an Asian Dust event in Korea was in 174 AD during the Silla Dynasty. The dust was known as "Uto (우토, 雨土)", meaning 'Raining Dirt/Earth', and was believed at the time to be the result of an angry god sending down dust instead of rain or snow. Specific records referring to Asian Dust events in Korea also exist from the Baekje, Goguryeo, and Joseon periods.

Composition

An analysis of Asian Dust clouds conducted in China in 2001 found that they contain high concentrations of silicon (24–32%), aluminium (5.9–7.4%), calcium (6.2–12%), and iron. Numerous toxic substances were also found, including mercury and cadmium from coal burning.

People further from the source of the dust are more often exposed to nearly invisible, fine dust particles that they can unknowingly inhale deep into their lungs, as coarse dust is too big to be deeply inhaled. After inhalation, these particles can cause long term scarring of lung tissue and induce cancer and lung disease.

Sulfur (an acid rain component), soot, ash, carbon monoxide, and other toxic pollutants including heavy metals (such as mercury, cadmium, chromium, arsenic, lead, zinc, copper) and other carcinogens, often accompany the dust storms, along with viruses, bacteria, fungi, pesticides, antibiotics, asbestos, herbicides, plastic ingredients, combustion products and hormone-mimicking phthalates. Though scientists had known that intercontinental dust plumes can ferry bacteria and viruses, "most people had assumed that the [sun's] ultraviolet light would sterilize these clouds," says microbiologist Dale W. Griffin, "We now find that isn't true."

Research done in 2014 found that China dust consists of fine dust and ultrafine dust particles. Fine dust consists of fine particular matter (PM). Particles smaller than 10 µm in diameter are classified as fine PM (PM10), while particles smaller than 2.5 µm in diameter are classified as ultrafine PM (PM2.5). Both fine and ultrafine dust particles impose dangers to health. Fine dust particles are small enough to penetrate deep into the lung alveoli. Ultrafine dust particles are so small that they also penetrate into the blood or lymphatic system through the lungs. Once in the bloodstream, ultrafine particles can even reach the brain or fetal organs.

Cause

The main cause of China dust is desertification of northern China, Mongolia, and Central Asia. Desertification in these regions owe to extensive logging in the forests and extensive harvesting of arable land. The origins of Asian dust are mostly located in developing countries; thus, most of these countries are undergoing rapid population growth. A study pointed to China's deforestation and soil erosion as indirect effects of the nation's booming population. High population growth in China has led to increasing demand for wood for housing and furniture as well as for firewood for cooking and heating. This increase in demand for wood (and firewood) has led to over-cutting of timber. At the same time, there has been an increase in demand for food, which has led to soil erosion due to overgrazing of arable land. For example, the northern part of Shaanxi Province and the Haixi area of Gansu Province was once a deep forest region, but the region now only has treeless mountains. Historically “because peasant farmers continue[d] to rely on low-technology agricultural techniques, they [had] to exploit virgin land to sustain a continually growing population. This led to a vicious cycle. Since traditional agricultural techniques rely heavily on human labor, people continued to have more children, which in turn led to more overgrazing.

Effects

Dust deposition in Beijing during the 2006 season.

Dangers to health

Perhaps the most important negative effect is on health. Many studies have found Asian dust to have negative effect on respiratory function and increase the occurrence of respiratory disease. Several research studies conducted in Korea and Japan focused on respiratory function performance by measuring peak expiratory flow. These studies found that individuals with respiratory diseases such as asthma suffer from the most adverse effects. There is also evidence that days with Asian Dust coupled with smog lead to increased mortality due to respiratory and cardiovascular diseases among inhabitants in affected regions. A recent study has also found PM2.5 to have an association with Parkinson's disease and other neurological diseases. The OECD predicted 1,069 premature deaths per million directly attributable to worsening air pollution in South Korea by 2060.

Areas affected by the dust experience decreased visibility and the dust is known to cause a variety of health problems, including sore throat and asthma in otherwise healthy people. Often, people are advised to avoid or minimize outdoor activities, depending on severity of storms. For those already with asthma or respiratory infections, it can be fatal. The dust has been shown to increase the daily mortality rate in one affected region by 1.7%.

Restrictions on outdoor activities

Due to the concerning health effects, residents of affected regions have reduced their exposure to Asian dust by refraining from outdoor activities. Despite the temperature rise to warm levels during spring season, popular outdoor destinations are empty on days with yellow dust advisory or warning. According to a survey in 2019, 97% of Koreans reported that they suffered from physical or mental distress due to Asian dust including fine dust during the time of the survey.

Since children are among the most vulnerable to fine dust particles, affected countries have come up with measures to minimize the detrimental effects on children; in 2017, South Korea's Ministry of Education have required all primary to high schools to create indoor spaces for sports and outdoor activities. Similar efforts are arising in professional sports. In 2019, the Korea Baseball Organization changed its regulations to cancel or suspend professional games during a severe fine dust warning.

Effects on industries

In addition to costs incurred by individuals, the rise of Asian dust has led to mixed pecuniary effects in different industries. First, the airline industry have been experiencing external costs due to the increasing severity of Asian dust. Dust collected on the plane surface can decrease the lift of the wings and react with moisture to corrode the aircraft's surface and decolorize the paint. As a result, during spring, when Asian dust levels are at the highest, airlines with aircraft in the affected region spend time and money to wash dust off their aircraft. Washing dust off a single B747 jumbo jet typically takes 6000 liters of water and eight hours with nine people working. Although cancellations stemming from yellow dust are rare, flights are cancelled due to poor visibility on the most severe days.

On the other hand, Asian dust also has led to some positive effects in certain industries. The demand for products to combat Asian dust has increased significantly. During a period of high fine dust levels in 2019, face mask and air purifier sales surged 458% and 414%, respectively, compared to the same period in 2018. The sale of dryers also surged 67% during the same period as outdoor air drying no longer became an option.

Socio-economic cost

Calculating the socioeconomic cost of yellow dust is a difficult endeavor. It requires estimating the negative effects on health, opportunity cost of outdoor activities, the cost of preventive measures, as well as the psychological distress. However, a research study estimated the total socio-economic cost of yellow dust using techniques including input-output analysis, integration of environmental-economic evaluation technique, contingent valuation method, etc. According to this study, the total socio-economic cost of yellow dust damage in South Korea in 2002 estimates between US$3.9 billion and $7.3 billion. This accounts for between 0.6% and 1.0% of the nation's GDP and US$81.48 and $152.52 per nation's resident.

Another study that focused on the total economic impacts of the yellow dust storms in Beijing concluded that it accounted for greater than 2.9% of the city's GDP in the year 2000.

Nutrient distribution

Asian dust is a historically significant contributor of soil nutrients for some North Pacific islands, including Hawaii.

Public economics

Negative externality

Asian dust is an example of a negative externality on society. Policy choices that favor rapid industrialization and deforestation in China, Mongolia, and other Central Asian regions impose social costs on Eastern countries, such as Korea, Japan, and Russia in the Far East.

The main cause of deforestation is extensive logging. Although the production of firewood and other wooden products induce deforestation, which leads to yellow dust as well as other ecological dangers, the social cost of yellow dust is not accounted for in the cost of production. This results in a market failure in which individual producers make decisions based on their private marginal cost - not accounting for the dust - rather than the social marginal cost, which includes the harms from the dust. Under a free market, the quantity of logs and other wooden goods produced exceeds the socially optimal outcome.

International conflict

China dust has been a source of international conflict between the Chinese and Korean governments. Although the major components of yellow dust are sand and materials from the earth's crust, various industrial pollutants and their by-products, including mercury, sulfuric acid, nitric acid and cadmium, have made the dust more harmful. Approximately 30% of sulfuric acid and 40% of nitric acid in ambient air in Korea may have migrated from China. To reduce the transboundary pollution from China, scientists have advocated for collaborative actions between Korea and China, including scientific, administrative, and political aspects.

In an effort to combat the worsening yellow dust levels, the Korean government has been working with the Chinese government. In January 2018, the two countries met at its 22nd meeting of the Republic of Korea-China Joint Committee on Environmental Cooperation, during which the two countries discussed increasing the cooperative efforts to fight air pollution, including yellow dust and fine dust, and marine pollution.

Severity

Asian Dust obscures the sun over Aizu-Wakamatsu, Japan, on April 2, 2007

Asian dust is not a new phenomenon. Historically, there have been records of Asian dust occurrences as early as 1150 B.C. in China and 174 A.D. in Korea. However, official weather data show a stark increase in its severity and frequency.

In the last half century, the number of days with reports of Asian dust has increased five-fold. According to an analysis on data from Korea Meteorological Administration (KMA), the average number of days with Asian dust in a given year was about two in the 1960s. However, this number has increased to 11 in 2000s. In 1960s and 1970s, each decade had 3 years that were Asian-dust free. However, starting from 2000s, there has not been a single year without Asian dust. In just four months of 2018, Gyeonggi Province of South Korea issued 42 dust warnings and advisories, which has increased from 36 in the same period in 2017. This reflects the increase in average dust concentration level from 132.88 ppm (parts per million) in 2017 to 149 ppm in 2018. The situation is worsening since the dust particles are staying in the air longer. The average duration has increased from 16.3 hours to 19.8 hours in the last two years.

Number of days of Yellow Dust Observations in Korea from 1960 to 2016

Asian dust, in combination with smog and general air pollution, has become so severe that it became a political issue in the South Korean presidential election in 2017. All three main candidates of the election—Moon Jae-in, Ahn Cheol-soo, and Hong Joon-pyo—promised to take measures to alleviate these growing national air pollution problems. In the first few months of 2017, Seoul had twice the number of ultrafine dust warnings, during which people were advised to limit outdoor activities and stay indoors when compared to 2016.

Shanghai on April 3, 2007, recorded an air quality index of 500. In the US, an index of 300 is considered "hazardous" and anything over 200 is "unhealthy". Desertification has intensified in China, as 1,740,000 km2 of land is "dry", which disrupts the lives of 400 million people and causes direct economic losses of 54 billion yuan (US$7 billion) per year, SFA figures show. These figures are probably vastly underestimated, as they only take into account direct effects, without including medical, pollution, and other secondary effects, as well as effects to neighboring nations.

El Niño also plays a role in Asian dust storms, because winter ice can keep dust from sweeping off the land.

Gobi Desert

From Wikipedia, the free encyclopedia

The Gobi Desert (Mongolian: Говь, ᠭᠣᠪᠢ, /ˈɡbi/; Chinese: 戈壁; pinyin: gēbì) is a large, cold desert and grassland region in northern China and southern Mongolia and is the sixth largest desert in the world. The name of the desert comes from the Mongolian word Gobi, used to refer to all of the waterless regions in the Mongolian Plateau, while in Chinese Gobi is used to refer to rocky, semi-deserts such as the Gobi itself rather than sandy deserts.

Geography

The Gobi measures 1,600 km (1,000 mi) from southwest to northeast and 800 km (500 mi) from north to south. The desert is widest in the west, along the line joining the Lake Bosten and the Lop Nor (87°–89° east). In 2007, it occupied an arc of land in area.

In its broadest definition, the Gobi includes the long stretch of desert extending from the foot of the Pamirs (77° east) to the Greater Khingan Mountains, 116–118° east, on the border of Manchuria; and from the foothills of the Altay, Sayan, and Yablonoi mountain ranges on the north to the Kunlun, Altyn-Tagh, and Qilian mountain ranges, which form the northern edges of the Tibetan Plateau, on the south.

A relatively large area on the east side of the Greater Khingan range, between the upper waters of the Songhua (Sungari) and the upper waters of the Liao-ho, is reckoned to belong to the Gobi by conventional usage. Some geographers and ecologists prefer to regard the western area of the Gobi region (as defined above): the basin of the Tarim in Xinjiang and the desert basin of Lop Nor and Hami (Kumul), as forming a separate and independent desert, called the Taklamakan Desert.

Much of the Gobi is not sandy, instead resembling exposed bare rock.

Climate

Gobi by NASA World Wind
Sand dunes in Inner Mongolia Autonomous Region, China
Flaming Cliffs in Mongolia
Sacred ovoo in the Gobi Desert
The sand dunes of Khongoryn Els, Gurvansaikhan NP, Mongolia
Remains of the Great Wall of China in the Gobi Desert

The Gobi is overall a cold desert, with frost and occasionally snow occurring on its dunes. Besides being quite far north, it is also located on a plateau roughly 910–1,520 m (2,990–4,990 ft) above sea level, which contributes to its low temperatures. An average of about 194 mm (7.6 in) of rain falls annually in the Gobi. Additional moisture reaches parts of the Gobi in winter as snow is blown by the wind from the Siberian Steppes. These winds may cause the Gobi to reach −40 °C (−40 °F) in winter to 45 °C (113 °F) in summer.

However, the climate of the Gobi is one of great extremes, with rapid changes of temperature of as much as 35 °C (63 °F) in 24-hour spans.

Temperature

(1190 m) Ulaanbaatar (1150 m)
Annual mean −2.5 °C (27.5 °F) −0.4 °C (31.3 °F)
January mean −26.5 °C (−15.7 °F) −21.6 °C (−6.9 °F)
July mean 17.5 °C (63.5 °F) 18.2 °C (64.8 °F)
Extremes −47 to 34 °C (−53 to 93 °F) −42.2 to 39.0 °C (−44.0 to 102.2 °F)

In southern Mongolia, the temperature has been recorded as low as −32.8 °C (−27.0 °F). In contrast, in Alxa, Inner Mongolia, it rises as high as 37 °C (99 °F) in July.

Average winter minimums are a frigid −21 °C (−6 °F), while summertime maximums are a warm 27 °C (81 °F). Most of the precipitation falls during the summer.

Although the southeast monsoons reach the southeast parts of the Gobi, the area throughout this region is generally characterized by extreme dryness, especially during the winter, when the Siberian anticyclone is at its strongest. The southern and central parts of the Gobi Desert have variable plant growth due to this monsoon activity. The more northern areas of the Gobi are very cold and dry, making it unable to support much plant growth; this cold and dry weather is attributed to Siberian-Mongolian high pressure cells. Hence, the icy dust and snowstorms of spring and early summer plus early January (winter).

Conservation, ecology, and economy

The Gobi Desert is the source of many important fossils finds, including the first dinosaur eggs, twenty-six of which, averaging 23 centimetres (9 in) in length, were uncovered in 1923.

Archeologists and paleontologists have done excavations in the Nemegt Basin in the northwestern part of the Gobi Desert (in Mongolia), which is noted for its fossil treasures, including early mammals, dinosaur eggs, and prehistoric stone implements, some 100,000 years old.

Despite the harsh conditions, these deserts and the surrounding regions sustain many animals species, some are even unique, including black-tailed gazelles, marbled polecats, wild Bactrian camels, Mongolian wild ass and sandplovers. They are occasionally visited by snow leopards, Gobi bears, and wolves. Lizards are especially well-adapted to the climate of the Gobi Desert, with approximately 30 species distributed across its southern Mongolian border. The most common vegetation in the Gobi desert are shrubs adapted to drought. These shrubs included gray sparrow's saltwort (Salsola passerina), gray sagebrush, and low grasses such as needle grass and bridlegrass. Due to livestock grazing, the amount of shrubs in the desert has decreased. Several large nature reserves have been established in the Gobi, including Gobi Gurvansaikhan National Park, Great Gobi A and Great Gobi B Strictly Protected Area.

The area is vulnerable to trampling by livestock and off-road vehicles (effects from human intervention are greater in the eastern Gobi Desert, where rainfall is heavier and may sustain livestock). In Mongolia, grasslands have been degraded by goats, which are raised by nomadic herders as source of cashmere wool.

Large copper deposits are being mined by Rio Tinto Group. The mine was and remains controversial. There was significant opposition in Mongolia's parliament to the terms under which the mine will proceed, and some are calling for the terms to be renegotiated. Specifically, the contention revolves primarily around the question of whether negotiations were fair (Rio Tinto is far better resourced) and whether Rio Tinto will pay adequate taxes on the revenues it derives from the mine (an agreement was reached whereby the operation will be exempt from windfall tax).

Desertification

The Gobi Desert is expanding through desertification, most rapidly on the southern edge into China, which is seeing 3,600 km2 (1,390 sq mi) of grassland overtaken every year. Dust storms increased in frequency between 1996 and 2016, causing further damage to China's agriculture economy. However, in some areas desertification has been slowed or reversed.

The northern and eastern boundaries between desert and grassland are constantly changing. This is mostly due to the climate conditions before the growing season, which influence the rate of evapotranspiration and subsequent plant growth.

The expansion of the Gobi is attributed mostly to human activities, locally driven by deforestation, overgrazing, and depletion of water resources, as well as to climate change.

China has tried various plans to slow the expansion of the desert, which have met with some success. The Three-North Shelter Forest Program (or "Green Great Wall") is a Chinese government tree-planting project begun in 1978 and set to continue through 2050. The goal of the program is to reverse desertification by planting aspen and other fast-growing trees on some 36.5 million hectares across some 551 counties in 12 provinces of northern China.

Ecoregions

The Gobi, broadly defined, can be divided into five distinct dry ecoregions, based on variations in climate and topography:

  • Eastern Gobi desert steppe, the easternmost of the Gobi ecoregions, covering an area of 281,800 km2 (108,804 sq mi). It extends from the Inner Mongolian Plateau in China northward into Mongolia. It includes the Yin Mountains and many low-lying areas with salt pans and small ponds. It is bounded by the Mongolian-Manchurian grassland to the north, the Yellow River Plain to the southeast, and the Alashan Plateau semi-desert to the southeast and east.
  • Alashan Plateau semi-desert, lies west and southwest of the Eastern Gobi desert steppe. It consists of the desert basins and low mountains lying between the Gobi Altai range on the north, the Helan Mountains to the southeast, and the Qilian Mountains and northeastern portion of the Tibetan Plateau on the southwest.
  • Gobi Lakes Valley desert steppe, ecoregion lies north of Alashan Plateau semi-desert, between the Gobi Altai range to the south and the Khangai Mountains to the north.
  • Dzungarian Basin semi-desert, includes the desert basin lying between the Altai mountains on the north and the Tian Shan range on the south. It includes the northern portion of China's Xinjiang province and extends into the southeastern corner of Mongolia. The Alashan Plateau semi-desert lies to the east, and the Emin Valley steppe to the west, on the China-Kazakhstan border.
  • Tian Shan range, separates the Dzungarian Basin semi-desert from the Taklamakan Desert, which is a low, sandy desert basin surrounded by the high mountain ranges of the Tibetan Plateau to the south and the Pamirs to the west. The Taklamakan Desert ecoregion includes the Desert of Lop.

Eastern Gobi desert steppe

Bactrian camels in the Bayankhongor Province of Mongolia
A Khulan (Mongolian wild ass) on a hill in the eastern Gobi of Mongolia at sunset

The surface is extremely diversified, although there are no great differences in vertical elevation. Between Ulaanbaatar (48°00′N 107°00′E) and the small lake of Iren-dubasu-nor (43°45′N 111°50′E), the surface is greatly eroded. Broad flat depressions and basins are separated by groups of flat-topped mountains of relatively low elevation 150 to 180 m (490 to 590 ft), through which archaic rocks crop out as crags and isolated rugged masses. The floors of the depressions lie mostly between 900 and 1,000 m (3,000 and 3,300 ft) above sea-level. Further south, between Iren-dutiasu-nor and the Yellow River, comes a region of broad tablelands alternating with flat plains, the latter ranging at altitudes of 1000–1100 m and the former at 1,070 to 1,200 m (3,510 to 3,940 ft). The slopes of the plateaus are more or less steep and are sometimes penetrated by "bays" of the lowlands.

As the border-range of the Hyangan is approached, the country steadily rises up to 1,370 m (4,490 ft) and then to 1,630 m (5,350 ft). Here small lakes frequently fill the depressions, though the water in them is generally salty or brackish. Both here and for 320 km (199 mi) south of Ulaanbaatar, streams are frequent and grass grows more or less abundantly. Through all the central parts, until the bordering mountains are reached, trees and shrubs are utterly absent. Clay and sand are the predominant formations; the watercourses, especially in the north, being frequently excavated 2 to 3 m (6 ft 7 in to 9 ft 10 in) deep. In many places in the flat, dry valleys or depressions farther south, beds of loess, 5 to 6 m (16 to 20 ft) thick, are exposed. West of the route from Ulaanbaatar to Kalgan, the country presents approximately the same general features, except that the mountains are not so irregularly scattered in groups but have more strongly defined strikes, mostly east to west, west-north-west to east-south-east, and west-south-west to east-north-east.

The altitudes are higher, those of the lowlands ranging from 1,000 to 1,700 m (3,300 to 5,600 ft), and those of the ranges from 200 to 500 m (660 to 1,640 ft) higher, though in a few cases they reach altitudes of 2,400 m (7,900 ft). The elevations do not form continuous chains, but make up a congeries of short ridges and groups rising from a common base and intersected by a labyrinth of ravines, gullies, glens, and basins. But the tablelands, built up of the horizontal red deposits of the Han-gai (Obruchev's Gobi formation) which are characteristic of the southern parts of eastern Mongolia, are absent here or occur only in one locality, near the Shara-muren river. They are greatly intersected by gullies or dry watercourses. Water is scarce, with no streams, no lakes, no wells, and precipitation falls seldom. The prevailing winds blow from the west and northwest, and the pall of dust overhangs the country as in the Taklamakan and the desert of Lop. Characteristic of the flora are wild garlic, Kalidium gracile, wormwood, saxaul, Nitraria schoberi, Caragana, Ephedra, saltwort and the grass Lasiagrostis splendens. The taana wild onion Allium polyrrhizum is the main browse eaten by many herd animals, and Mongolians claim that this is essential in producing the proper, hazelnut-like notes of camel airag (fermented milk).

The vast desert is crisscrossed by several trade routes, some of which have been in use for thousands of years. Among the most important are those from Kalgan (at the Great Wall) to Ulaanbaatar (960 km (597 mi)); from Jiuquan (in Gansu) to Hami 670 km (416 mi); from Hami to Beijing (2,000 km (1,243 mi)); from Hohhot to Hami and Barkul; and from Lanzhou (in Gansu) to Hami.

Alashan Plateau semi-desert

Alxa Left Banner, Inner Mongolia, China

The southwestern portion of the Gobi, known also as the Xitao and the Little Gobi, fills the space between the great north loop of the Yellow River on the east, the Ejin River on the west, and the Qilian Mountains and narrow rocky chain of Longshou, 3,200 to 3,500 m (10,500 to 11,500 ft) in altitude, on the southwest. The Ordos Desert, which covers the northeastern portion of the Ordos Plateau, in the great north loop of the Yellow River, is part of this ecoregion. It belongs to the middle basin of the three great depressions into which Potanin divides the Gobi as a whole.

"Topographically," says Nikolai Przhevalsky, "it is a perfectly level plain, which in all probability once formed the bed of a huge lake or inland sea." He concludes this based on the level area of the region as a whole, the hard saline clay and the sand-strewn surface and, lastly, the salt lakes which occupy its lowest parts. For hundreds of kilometers, nothing can be seen but bare sands; in some places, they continue so far without a break that the Mongols call them Tengger (i.e. sky). These vast expanses are absolutely waterless, nor do any oases relieve the unbroken stretches of yellow sand, which alternate with equally vast areas of saline clay or, nearer the foot of the mountains, with barren shingle. Although on the whole a level country with a general altitude of 1,000 to 1,500 m (3,300 to 4,900 ft), this section, like most other parts of the Gobi, is crowned by a network of hills and broken ranges of at least 300 m in elevation. The vegetation is confined to a few varieties of bushes and a dozen kinds of grasses and herbs, the most conspicuous being saxaul (Haloxylon ammondendron) and Agriophyllum gobicum. The others include prickly convolvulus, field wormwood (Artemisia campestris), acacia, Inula ammophila, Sophora flavescens, Convolvulus ammanii, Peganum and Astragalus species, but all dwarfed, deformed and starved. The fauna consists of little but antelope, wolf, fox, hare, hedgehog, marten, numerous lizards and a few birds, e.g. the sandgrouse, lark, stonechat, sparrow, crane, Mongolian ground jay (Podoces hendersoni), horned lark (Eremophila alpestris), and crested lark (Galerida cristata).

Dzungarian Basin semi-desert

The structure here is that of the mighty T'ien Shan, or Heavenly Mountains, running from west to east. It divides the northern one-third of Sinkiang from the southern two-thirds. On the northern side, rivers formed from the snow and glaciers of the high mountains break through barren foothill ranges and flow out into an immense, hollow plain. Here the rivers begin to straggle and fan out, and form great marshes with dense reed-beds. Westerners call this terrain the Dzungarian desert. The Chinese also call it a desert, but the Mongols call it a 'gobi'—that is, a land of thin herbage, more suitable for camels than for cows, but capable also, if herds are kept small and moved frequently, of sustaining horses, sheep, and goats. The herbage comprises a high proportion of woody, fragrant plants. Gobi mutton is the most aromatic in the world.

The Yulduz valley or valley of the Haidag-gol (43°N 83°E43°N 86°E) is a mini desert enclosed by two prominent members of the Shanashen Trahen Osh mountain range, namely the chucis and the kracenard pine rallies, running perpendicular and far from one another. As they proceed south, they transcend and transpose, sweeping back on east and west respectively, with Lake Bosten in between. These two ranges mark the northern and the southern edges respectively of a great swelling, which extends eastward for nearly twenty degrees of longitude. On its northern side, the Chol-tagh descends steeply, and its foot is fringed by a string of deep depressions, ranging from Lukchun (130 m (427 ft) below sea level) to Hami (850 m (2,789 ft) above sea-level). To the south of the Kuruk-tagh lie the desert of Lop Nur, the Kum-tagh desert, and the valley of the Bulunzir-gol. To this great swelling, which arches up between the two border-ranges of the Chol-tagh and Kuruk-tagh, the Mongols give the name of Ghashuun-Gobi or "Salt Desert". It is some 130 to 160 km (81 to 99 mi) across from north to south, and is traversed by a number of minor parallel ranges, ridges and chains of hills. Down its middle runs a broad stony valley, 40 to 80 km (25 to 50 mi) wide, at an elevation of 900 to 1,370 m (2,950 to 4,490 ft). The Chol-tagh, which reaches an average altitude of 1,800 m (5,900 ft), is absolutely sterile, and its northern foot rests upon a narrow belt of barren sand, which leads down to the depressions mentioned above.[2]

The Kuruk-tagh is the greatly disintegrated, denuded and wasted relic of a mountain range which used to be of incomparably greater magnitude. In the west, between Lake Bosten and the Tarim, it consists of two, possibly of three, principal ranges, which, although broken in continuity, run generally parallel to one another, and embrace between them numerous minor chains of heights. These minor ranges, together with the principal ranges, divide the region into a series of long; narrow valleys, mostly parallel to one another and to the enclosing mountain chains, which descend like terraced steps, on the one side towards the depression of Lukchun and on the other towards the desert of Lop.

In many cases these latitudinal valleys are barred transversely by ridges or spurs, generally elevations en masse of the bottom of the valley. Where such elevations exist, there is generally found, on the east side of the transverse ridge, a cauldron-shaped depression, which some time or other has been the bottom of a former lake, but is now nearly a dry salt-basin. The surface configuration is in fact markedly similar to that which occurs in the inter-mount latitudinal valleys of the Kunlun Mountains. The hydrography of the Ghashiun-Gobi and the Kuruk-tagh is determined by the aforementioned arrangements of the latitudinal valleys. Most of the principal streams, instead of flowing straight down these valleys, cross them diagonally and only turn west after they have cut their way through one or more of the transverse barrier ranges.

To the highest range on the great swelling Grigory Grum-Grshimailo gives the name of Tuge-tau, its altitude being 2,700 m (8,858 ft) above the level of the sea and some 1,200 m (3,937 ft) above the crown of the swelling itself. This range he considers to belong to the Choltagh system, whereas Sven Hedin would assign it to the Kuruk-tagh. This last, which is pretty certainly identical with the range of Kharateken-ula (also known as the Kyzyl-sanghir, Sinir, and Singher Mountains), that overlooks the southern shore of the Lake Bosten, though parted from it by the drift-sand desert of Ak-bel-kum (White Pass Sands), has at first a west-northwest to east-southeast strike, but it gradually curves round like a scimitar towards the east-northeast and at the same time gradually decreases in elevation.

At 91° east, where the principal range of the Kuruk-tagh system wheels to the east-northeast, four of its subsidiary ranges terminate, or rather die away somewhat suddenly, on the brink of a long narrow depression (in which Sven Hedin sees a northeast bay of the former great Central Asian lake of Lop-nor), having over against them the écheloned terminals of similar subordinate ranges of the Pe-shan (Boy-san) system (see below). The Kuruk-tagh is throughout a relatively low, but almost completely barren range, being entirely destitute of animal life, save for hares, antelopes and wild camels, which frequent its few small, widely scattered oases. The vegetation, which is confined to these same areas, is of the scantiest and is mainly confined to bushes of saxaul (Haloxylon), anabasis, reeds (kamish), tamarisks, poplars, and Ephedra.

History

Prehistory

There is little information about early habitation of the Gobi desert.

Lisa Janz has proposed a system of nomenclature for early Gobi desert habitation. They are Oasis I, Oasis II, Oasis III. 

Oasis I is equivalent to the Mesolithic from 13500 cal BP to 8000 cal BP. During this time people began using oases. It is characterized by:

Oasis II is equivalent to the Neolithic from 8000 cal BP to 5000 cal BP. People used the oases extensively. It was characterized by:

  • micro blades
  • milling stones
  • chipped macro tools
  • adzes
  • axes
  • high quality cryptocrystallines
  • honeycomb imprinted, corded, string paddled, low and high fired pottery with a sand and gravel mixture. 

Starting around 8000 cal BP there was a warm wet phase in the Gobi desert. By 7500 cal BP lake levels in the Western Gobi reached their peak. Around this time there was meadow steppe vegetation around lakes. In Ulaan Nuur there may have been shrubby riparian woodlands.

Oasis III is equivalent to the Bronze Age from 5000 cal BP to 3000 cal BP. It is characterized by:

Bronze Age herder burials have been found in the Gobi desert, as well as Karasuk bronze knives, and Mongolian deer stones.  Between 5000 cal BP and 4500 cal BP there was a period of desertification.  Due to the increasing aridity between 3500 cal BP and 3000 cal BP there was a decline in human habitation in the Gobi desert. 

European and American exploration

The Gobi had a long history of human habitation, mostly by nomadic peoples. The name of Gobi means desert in Mongolian. The region was inhabited mostly by Mongols, Uyghurs, and Kazakhs.

The Gobi Desert as a whole was known only very imperfectly to outsiders, as information was confined to observations by individual travelers engaging in their respective itineraries across the desert. Among the European and American explorers who contributed to the understanding of the Gobi, the most important were the following:

Romance (love)

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