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Sunday, December 29, 2019

Kuwaiti oil fires

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Kuwaiti_oil_fires
 
Smoke plumes from a few of the Kuwaiti Oil Fires on April 7, 1991.
 
The Kuwaiti oil fires were caused by Iraqi military forces setting fire to a reported 605 to 732 oil wells along with an unspecified number of oil filled low-lying areas, such as oil lakes and fire trenches, as part of a scorched earth policy while retreating from Kuwait in 1991 due to the advances of Coalition military forces in the Persian Gulf War. The fires were started in January and February 1991, and the first well fires were extinguished in early April 1991, with the last well capped on November 6, 1991.

Motives

Oil well fires, south of Kuwait City. (Photo taken from inside a UH-60 Blackhawk; the door frame is the black bar on the right of the photo)
 
The dispute between Iraq and Kuwait over alleged slant-drilling in the Rumaila oil field was one of the reasons for Iraq's invasion of Kuwait in 1990.

Kuwaiti oil well fire, south of Kuwait City, March, 1991
 
In addition, Kuwait had been producing oil above treaty limits established by OPEC. By the eve of the Iraqi invasion, Kuwait had set production quotas to almost 1.9 million barrels per day (300,000 m3/d), which coincided with a sharp drop in the price of oil. By the summer of 1990, Kuwaiti overproduction had become a serious point of contention with Iraq.

Some analysts have speculated that one of Saddam Hussein's main motivations in invading Kuwait was to punish the ruling al-Sabah family in Kuwait for not stopping its policy of overproduction, as well as his reasoning behind the destruction of said wells.

It is also hypothesized that Iraq decided to destroy the oil fields to achieve a military advantage, believing the intense smoke plumes serving as smoke screens created by the burning oil wells would inhibit Coalition offensive air strikes, foil allied precision guided weapons and spy satellites, and could screen Iraq’s military movements. Furthermore, it is thought that Iraq’s military leaders may have regarded the heat, smoke, and debris from hundreds of burning oil wells as presenting a formidable area denial obstacle to Coalition forces. The onset of the oil well destruction supports this military dimension to the sabotage of the wells; for example, during the early stage of the Coalition air campaign, the number of oil wells afire was relatively small but the number increased dramatically in late February with the arrival of the ground war.

The Iraqi military combat engineers also released oil into low-lying areas for defensive purposes against infantry and mechanized units along Kuwait’s southern border, by constructing several "fire trenches" roughly 1 kilometer long, 3 meters wide, and 3 meters deep to impede the advance of Coalition ground forces.

The military use of the land based fires should also be seen in context with the coinciding, deliberate, sea based Gulf War oil spill, the apparent strategic goal of which was to foil a potential amphibious landing by U.S. Marines.

Extent

The Kuwaiti oil fires were not just limited to burning oil wells, one of which is seen here in the background, but burning "oil lakes", seen in the foreground, also contributed to the smoke plumes, particularly the sootiest/blackest of them (1991).
 
As an international coalition under United States command assembled in anticipation of an invasion of Iraqi-occupied Kuwait, the Iraqi regime decided to destroy as much of Kuwait's oil reserves and infrastructure as possible before withdrawing from that country. As early as December 1990, Iraqi forces placed explosive charges on Kuwaiti oil wells. The wells were systematically sabotaged beginning on January 16, 1991, when the allies commenced air strikes against Iraqi targets. On February 8, satellite images detected the first smoke from burning oil wells. The number of oil fires peaked between February 22 and 24, when the allied ground offensive began.

According to the U.S. Environmental Protection Agency's report to Congress, "the retreating Iraqi army set fire to or damaged over 700 oil wells, storage tanks, refineries, and facilities in Kuwait." Estimates placed the number of oil well fires from 605 to 732. A further thirty-four wells had been destroyed by heavy coalition bombing in January. The Kuwait Petroleum Company's estimate as of September 1991 was that there had been 610 fires, out of a total of 749 facilities damaged or on fire along with an unspecified number of oil filled low-lying areas, such as "oil lakes" and "fire trenches". These fires constituted approximately 50% of the total number of oil well fires in the history of the petroleum industry, and temporarily damaged or destroyed approximately 85% of the wells in every major Kuwaiti oil field.

Concerted efforts to bring the fires and other damage under control began in April 1991. During the uncontrolled burning phase from February to April, various sources estimated that the ignited wellheads burnt through between four and six million barrels of crude oil, and between seventy and one hundred million cubic meters of natural gas per day. Seven months later, 441 facilities had been brought under control, while 308 remained uncontrolled. The last well was capped on November 6, 1991. The total amount of oil burned is generally estimated at about one billion barrels of the entire one hundred four billion supply. Almost one in every 100 barrels was destroyed forever. Daily global oil consumption in 2015 is about 91.4 million barrels; the oil lost to combustion would last 11 days at modern usage rates. 

Military effects

USAF aircraft fly over burning Kuwaiti oil wells (1991)
 
The oil fires caused a dramatic decrease in air quality, causing respiratory problems for many soldiers on the ground without gas masks (1991).
 
United States Marines approach burning oilfields during ground war of the Gulf War (1991).
 
On March 21, 1991, a Royal Saudi Air Force C-130H crashed in heavy smoke due to the Kuwaiti oil fires on approach to Ras Mishab Airport, Saudi Arabia. 92 Senegalese soldiers and 6 Saudi crew members were killed, the largest accident among Coalition forces.

The smoke screening was also used by Iraqi anti-armor forces to a successful extent in the Battle of Phase Line Bullet, having aided in achieving the element of surprise against advancing Bradley (IFV)s, along with increasing the general fog of war.

The fires burned out of control because of the dangers of sending in firefighting crews during the war. Land mines had been placed in areas around the oil wells and military demining was necessary before the fires could be put out. Around 5 million barrels (790,000 m3) of oil were lost each day. Eventually, privately contracted crews extinguished the fires, at a total cost of US$1.5 billion to Kuwait. By that time, however, the fires had burned for approximately ten months, causing widespread pollution.

The fires have been linked with what was later deemed Gulf War Syndrome, a chronic disorder afflicting military veterans and civilian workers that include fatigue, muscle pain, and cognitive problems; however, studies have indicated that the firemen who capped the wells did not report any of the symptoms that the soldiers experienced. The causes of Gulf War Syndrome have yet to be determined. 

From the perspective of ground forces, apart from the occasional "oil rain" experienced by troops very close to spewing wells, one of the more commonly experienced effects of the oil field fires were the ensuing smoke plumes which rose into the atmosphere and then precipitated or fell out of the air via dry deposition and by rain. The pillar-like plumes frequently broadened and joined up with other smoke plumes at higher altitudes, producing a cloudy grey overcast effect, as only about 10% of all the fires corresponding with those that originated from "oil lakes" produced pure black soot filled plumes, 25% of the fires emitted white to grey plumes, while the remainder emitted plumes with colors between grey and black. For example, one Gulf War veteran stated:
It was like a cloudy day all day long, in fact, we didn’t realize it was smoke at first. The smoke was about 500 feet above us, so we couldn’t see the sky. However, we could see horizontally for long distances with no problem. We knew it was smoke when the mucous from our nostrils started to look black..."
A paper published in 2000 analyzed the degree of exposure by troops to particulate matter, which included soot but the paper focused more-so on silica sand, which can produce silicosis. The paper included troop medical records, and in its conclusion: "A literature review indicated negligible to nonexistent health risk from other inhaled particulate material (other than silica) during the Gulf War". 

Extinguishing efforts

The burning wells needed to be extinguished as, without active efforts, Kuwait would lose billions of dollars in oil revenues. It was predicted that the fires would burn from two to five years before losing pressure and going out on their own, optimists estimating two years and pessimists estimating five while the majority estimated three years until this occurred.

The companies responsible for extinguishing the fires initially were Bechtel, Red Adair Company (now sold off to Global Industries of Louisiana), Boots and Coots, and Wild Well Control. Safety Boss was the fourth company to arrive but ended up extinguishing and capping the most wells of any other company: 180 of the 600. Other companies including Cudd Well/Pressure Control, Neal Adams Firefighters, and Kuwait Wild Well Killers were also contracted.

According to Larry H. Flak, a petroleum engineer for Boots and Coots International Well Control, 90% of all the 1991 fires in Kuwait were put out with nothing but sea water, sprayed from powerful hoses at the base of the fire. The extinguishing water was supplied to the arid desert region by re-purposing the oil pipelines that prior to the arson attack had pumped oil from the wells to the Persian Gulf. The pipeline had been mildly damaged but, once repaired, its flow was reversed to pump Persian gulf seawater to the burning oil wells. The extinguishing rate was approximately 1 every 7–10 days at the start of efforts but then with experience gained and the removal of the mine fields that surrounded the burning wells, the rate increased to 2 or more per day.

For stubborn oil well fires, the use of a gas turbine to blast a large volume of water at high velocity at the fire proved popular with firefighters in Kuwait and was brought to the region by Hungarians equipped with MiG-21 engines mounted originally on a T-34 (later replaced with T-55) tank, called Big wind. It extinguished 9 fires in 43 days. 

In fighting a fire at a directly vertical spewing wellhead, high explosives, such as dynamite were used to create a blast wave that pushes the burning fuel and local atmospheric oxygen away from the well. (This is a similar principle to blowing out a candle.) The flame is removed and the fuel can continue to spill out without igniting. Generally, explosives were placed within 55 gallon drums, the explosives surrounded by fire retardant chemicals, and then the drums are wrapped with insulating material with a horizontal crane being used to bring the drum as close to the burning area as possible.

The firefighting teams titled their occupation as "Operation Desert Hell" after Operation Desert Storm.

Fire documentaries

The fires were the subject of a 1992 IMAX documentary film, Fires of Kuwait, which was nominated for an Academy Award. The film includes footage of the Hungarian team using their jet turbine extinguisher.

Lessons of Darkness is a 1992 film by director Werner Herzog that explores of the ravaged oil fields of post-Gulf War Kuwait.

Betchel Corporation produced a short documentary titled Kuwait: Bringing Back the Sun that summarizes and focuses upon the fire fighting efforts, which were dubbed the Al-Awda (Arabic for "The Return") project.

Environmental impact


Oil fire smoke


Immediately following Iraq’s invasion of Kuwait, predictions were made of an environmental disaster stemming from Iraqi threats to blow up captured Kuwaiti oil wells. Speculation ranging from a nuclear winter type scenario, to heavy acid rain and even short term immediate global warming were presented at the World Climate Conference in Geneva that November.

On January 10, 1991, a paper appearing in the Journal Nature, stated Paul Crutzen's calculations that the setting alight of the Kuwait oil wells would produce a "nuclear winter", with a cloud of smoke covering half of the Northern Hemisphere after 100 days had passed and beneath the cloud, temperatures would be reduced by 5-10 Celsius. This was followed by articles printed in the Wilmington Morning Star and the Baltimore Sun newspapers in mid to late January 1991, with the popular TV scientist personality of the time, Carl Sagan, who was also the co-author of the first few nuclear winter papers along with Richard P. Turco, John W. Birks, Alan Robock and Paul Crutzen together collectively stated that they expected catastrophic nuclear winter like effects with continental sized impacts of "sub-freezing" temperatures as a result if the Iraqis went through with their threats of igniting 300 to 500 pressurized oil wells and they burned for a few months.

Later when Operation Desert Storm had begun, Dr. S. Fred Singer and Carl Sagan discussed the possible environmental impacts of the Kuwaiti petroleum fires on the ABC News program Nightline. Sagan again argued that some of the effects of the smoke could be similar to the effects of a nuclear winter, with smoke lofting into the stratosphere, a region of the atmosphere beginning around 43,000 feet (13,000 m) above sea level at Kuwait, resulting in global effects and that he believed the net effects would be very similar to the explosion of the Indonesian volcano Tambora in 1815, which resulted in the year 1816 being known as the Year Without a Summer

He reported on initial modeling estimates that forecast impacts extending to south Asia, and perhaps to the northern hemisphere as well. Singer, on the other hand, said that calculations showed that the smoke would go to an altitude of about 3,000 feet (910 m) and then be rained out after about three to five days and thus the lifetime of the smoke would be limited. Both height estimates made by Singer and Sagan turned out to be wrong, albeit with Singer's narrative being closer to what transpired, with the comparatively minimal atmospheric effects remaining limited to the Persian Gulf region, with smoke plumes, in general, lofting to about 10,000 feet (3,000 m) and a few times as high as 20,000 feet (6,100 m).

Along with Singer's televised critique, Richard D. Small criticized the initial Nature paper in a reply on March 7, 1991 arguing along similar lines as Singer.

Sagan later conceded in his book The Demon-Haunted World that his prediction did not turn out to be correct: "it was pitch black at noon and temperatures dropped 4–6 °C over the Persian Gulf, but not much smoke reached stratospheric altitudes and Asia was spared."

At the peak of the fires, the smoke absorbed 75 to 80% of the sun’s radiation. The particles rose to a maximum of 20,000 feet (6,100 m), but were scavenged by cloud condensation nuclei from the atmosphere relatively quickly.

Sagan and his colleagues expected that a "self-lofting" of the sooty smoke would occur when it absorbed the sun's heat radiation, with little to no scavenging occurring, whereby the black particles of soot would be heated by the sun and lifted/lofted higher and higher into the air, thereby injecting the soot into the stratosphere where it would take years for the sun blocking effect of this aerosol of soot to fall out of the air, and with that, catastrophic ground level cooling and agricultural impacts in Asia and possibly the Northern Hemisphere as a whole.

In retrospect, it is now known that smoke from the Kuwait oil fires only affected the weather pattern throughout the Persian Gulf and surrounding region during the periods that the fires were burning in 1991, with lower atmospheric winds blowing the smoke along the eastern half of the Arabian Peninsula, and cities such as Dhahran and Riyadh, and countries such as Bahrain experienced days with smoke filled skies and carbon soot rainout/fallout.

Thus the immediate consequence of the arson sabotage was a dramatic regional decrease in air quality, causing respiratory problems for many Kuwaitis and those in neighboring countries.

According to the 1992 study from Peter Hobbs and Lawrence Radke, daily emissions of sulfur dioxide (which can generate acid rain) from the Kuwaiti oil fires were 57% of that from electric utilities in the United States, the emissions of carbon dioxide were 2% of global emissions and emissions of soot reached 3400 metric tons per day.

In a paper in the DTIC archive, published in 2000, it states that "Calculations based on smoke from Kuwaiti oil fires in May and June 1991 indicate that combustion efficiency was about 96% in producing carbon dioxide. While, with respect to the incomplete combustion fraction, Smoke particulate matter accounted for 2% of the fuel burned, of which 0.4% was soot."[With the remaining 2%, being oil that did not undergo any initial combustion].

Smoke documentary

Peter V. Hobbs also narrated a short amateur documentary titled Kuwait Oil Fires that followed the University of Washington/UW's "Cloud and Aerosol Research Group" as they flew through, around and above the smoke clouds and took samples, measurements, and video of the smoke clouds in their Convair C-131(N327UW) Aerial laboratory.

Oil spills

A 2008 picture of the mummified remains of a bird, encrusted within the top hard layer of a dry oil lake in the Kuwaiti desert.
 
Although scenarios that predicted long-lasting environmental impacts on a global atmospheric level due to the burning oil sources did not transpire, long-lasting ground level oil spill impacts were detrimental to the environment regionally.

Forty-six oil wells are estimated to have gushed, and before efforts to cap them began, they were releasing approximately 300,000-400,000 barrels of oil per day, with the last gusher being capped occurring in the latter days of October 1991.

The Kuwaiti Oil Minister estimated between twenty-five and fifty million barrels of unburned oil from damaged facilities pooled to create approximately 300 oil lakes, that contaminated around 40 million tons of sand and earth. The mixture of desert sand, unignited oil spilled and soot generated by the burning oil wells formed layers of hard "tarcrete", which covered nearly five percent of Kuwait's land mass.

Cleaning efforts were led by the Kuwait Institute for Scientific Research and the Arab Oil Co., who tested a number of technologies including the use of petroleum-degrading bacteria on the oil lakes.

Vegetation in most of the contaminated areas adjoining the oil lakes began recovering by 1995, but the dry climate has also partially solidified some of the lakes. Over time the oil has continued to sink into the sand, with potential consequences for Kuwait's small groundwater resources.

The land based Kuwaiti oil spill surpassed the Lakeview Gusher, which spilled nine million pounds in 1910, as the largest oil spill in recorded history.

Six to eight million barrels of oil were directly spilled into the Persian Gulf, which became known as the Gulf War oil spill.

Comparable incidents

During the second US invasion of Iraq in 2003, approximately 40 oil wells were set on fire in the Persian gulf within Iraqi territory, ostensibly to once again hinder the invasion.

The Kuwait Wild Well Killers, who successfully extinguished 41 of the Kuwait oil well fires in 1991, used their experience to tackle blazes in the Iraqi Rumaila oilfields in 2003.

In popular culture

  • The fires are featured in Werner Herzog's 1992 film Lessons of Darkness.
  • There was also a flyover as well as some ground shots of the oil fires in the 1992 nonverbal film Baraka, shot on 70mm Todd-AO film.
  • The 2004 film The Manchurian Candidate included a scene set in Kuwait in February 1991, with burning oil fields visible in the background.
  • In the 2005 film Jarhead, the oil fires burn continuously throughout the 1991 invasion of Iraq, and its effects—an unceasing rain of unburned oil and smoke-filled skies, feature prominently in the story.
  • In the 1999 film Three Kings, oil fires are featured in multiple scenes.
  • In the 1990s TV series The X-Files, the "Black Oil" is believed to be an alien disease causing agent, evoking the conspiracy theory that Gulf War syndrome was caused by the Kuwaiti oil. The 2001 episode, "Vienen", includes an oil-rig fire that could potentially disperse The Black Oil contagion.
  • In the 2002 video game Eternal Darkness the fires are featured in the final level of the game as a key plot point.

Saturday, December 28, 2019

Arabian Desert

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Arabian_Desert
 
Arabian Desert
Arabian Desert.png
A satellite image of the Arabian Desert by NASA World Wind
Length2,100 km (1,300 mi)
Width1,100 km (680 mi)
Area2,330,000 km2 (900,000 sq mi)
Naming
Native nameٱلصَّحْرَاء ٱلْعَرَبِيَّة (in Arabic)
Geography
Countries
Coordinates18.2672°N 42.3681°E

The Arabian Desert is a vast desert wilderness in Western Asia. It stretches from Yemen to the Persian Gulf and Oman to Jordan and Iraq. It occupies most of the Arabian Peninsula, with an area of 2,330,000 square kilometers (900,000 sq mi). It is the fifth largest desert in the world, and the largest in Asia. At its center is Ar-Rub'al-Khali (The Empty Quarter), one of the largest continuous bodies of sand in the world.

Gazelles, oryx, sand cats, and spiny-tailed lizards are just some of the desert-adapted species that survive in this extreme environment, which features everything from red dunes to deadly quicksand. The climate is mostly dry (the major part receives around 100 mm (3.9 in) of rain per year but some very rare places receive as little as 50 mm), and temperatures oscillate between very high heat and seasonal night time freezes. It is part of the deserts and xeric shrublands biome and the Palearctic ecozone.

The Arabian desert ecoregion holds little biodiversity, although a few endemic plants grow here. Many species, such as the striped hyena, jackal and honey badger have become extirpated due to hunting, human encroachment and habitat destruction. Other species have been successfully re-introduced, such as the Arabian sand gazelle, and are protected at a number of reserves. Overgrazing by livestock, off-road driving, and human destruction of habitat are the main threats to this desert ecoregion.

Geology and geography

Map of the Arabian Desert. Ecoregions as delineated by the WWF. The yellow line encloses the ecoregion called "Arabian Desert and East Sahero-Arabian xeric shrublands", and two smaller, closely related ecoregions called "Persian Gulf desert and semi-desert" and "Red Sea Nubo-Sindian tropical desert and semi-desert". National boundaries are shown in black. Satellite image from NASA.
 
Detailed geological features:
  • A corridor of sandy terrain known as the Ad-Dahna desert connects the large An-Nafud desert (65,000 km2 or 40,389 square miles) in the north of Saudi Arabia to the Rub' Al-Khali in the south-east.
  • The Tuwaiq escarpment is a region of 800 km (500 mi) arc of limestone cliffs, plateaux, and canyons.
  • Brackish salt flats: the quicksands of Umm al Samim.
  • The Wahiba Sands of Oman: an isolated sand sea bordering the east coast
  • The Rub' Al-Khali desert is a sedimentary basin elongated on a south-west to north-east axis across the Arabian Shelf. At an altitude of 1,000 metres (3,300 ft), the rock landscapes yield the place to the Rub' al-Khali, vast wide of sand of the Arabian desert, whose extreme southern point crosses the centre of Yemen. The sand overlies gravel or Gypsum Plains and the dunes reach maximum heights of up to 250 m (820 ft). The sands are predominantly silicates, composed of 80 to 90% of quartz and the remainder feldspar, whose iron oxide-coated grains color the sands in orange, purple, and red.

Ecology and natural resources

Natural resources available in the Arabian Desert include oil, natural gas, phosphates, and sulfur.

The Rub'al-Khali has very limited floristic diversity. There are only 37 plant species, 20 recorded in the main body of the sands and 17 around the outer margins. Of these 37 species, one or two are endemic. Vegetation is very diffuse but fairly evenly distributed, with some interruptions of near sterile dunes. Some typical plants are:
Other widespread species are:
Very few trees are found except at the outer margin (typically Acacia ehrenbergiana and Prosopis cineraria). Other species are a woody perennial Calligonum comosum, and annual herbs such as Danthonia forskallii.

The Asiatic cheetah and Asiatic lion used to be here. 

Climate

The Arabian Desert has a subtropical, hot desert climate, similar to the climate of the Sahara Desert; the world's largest hot desert. The Arabian Desert is actually an extension of the Sahara Desert over the Arabian peninsula. The climate is mainly hot and dry with plenty of sunshine throughout the year. The rainfall amount is generally around 100 mm, and the driest areas can receive between 30 and 40 mm of annual rain. Such dryness remains rare throughout the desert, however. There are few hyperarid areas in the Arabian Desert, in contrast with the Sahara Desert, where more than half of the area is hyperarid (annual rainfall below 50 mm). The sunshine duration in the Arabian Desert is very high by global standards, between 2,900 hours (66.2% of daylight hours) and 3,600 hours (82.1% of daylight hours), but it is typically around 3,400 hours (77.6% of daylight hours), thus clear-sky conditions prevail over the region and cloudy periods are intermittent. Even though the sun and moon are bright, dust and humidity cause lower visibility at ground level. The temperatures remain high all year round. Average high temperatures in summer are generally over 40 °C (104 °F) at low elevations, and can even soar to 48 °C (114.8 °F) at extremely low elevations, especially along the Persian Gulf near sea level. Average low temperatures in summer remain high, over 20 °C (68 °F) and sometimes over 30 °C (77 °F) in the southernmost regions. Record high temperatures are above 50 °C (122 °F) in much of the desert, due in part to very low elevation.

Political borders

The desert lies mostly in Saudi Arabia, extending into the surrounding countries of Egypt (Sinai), southern Iraq and southern Jordan. The Arabian desert is bordered by 5 countries. Bordering the Persian Gulf, there is an extension into Qatar and, further east, the region covers almost all of Abu Dhabi in the United Arab Emirates (UAE). The Rub'al-Khali crosses over from Saudi Arabia into western Oman and eastern Yemen

People, language and cultures

The area is home to several different cultures, languages, and peoples, with Islam as the predominant faith. The major ethnic group in the region is the Arabs, whose primary language is Arabic

Settlements

In the center of the desert lies Riyadh, the capital of Saudi Arabia, with more than 7 million inhabitants. Other large cities, such as Dubai, Abu Dhabi, or Kuwait City, lie on the coast of the Persian Gulf.

Ecological threats


Military activity

Weaponry used by the United States during the Gulf War also poses a huge risk to the environmental stability of the area. Tank columns in the desert plains may disrupt the fragile stability that exists in the desert currently. In 1991, the movement of US tanks over the desert damaged the top protective layer of the desert soil. As a result, a sand dune was released and has started slowly moving downhill. Some people fear this dune could ultimately reach Kuwait City.

Conservation

The conservation status of the desert is critical/endangered, with species including the sand gazelle and white oryx threatened, and honey badgers, jackals, and striped hyaenas already extirpated.

No formal protected areas exist, but a number of protected areas are planned for Abu Dhabi.

Oil spills

In January 1991 during the Gulf War, Iraqi forces released about 1.7 million m³ (11 million barrels) of oil from storage tanks and tankers directly into the Persian Gulf. In February, they also destroyed 1,164 Kuwaiti oil wells. It took nine months to extinguish these oil fires. These oil spills contaminated 1,000 km (620 mi) of Persian Gulf coast.

The result of the pollution was the death of thousands of water birds and serious damage to the Persian Gulf's aquatic ecosystem, particularly shrimp, sea turtles, dugongs, whales, dolphins and fish.
The damaged wells also released 10 million m³ (60 million barrels) of oil into the desert and formed lakes (total surface of 49 square kilometers).

Gobi Desert (updated)

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

Gobi Desert
GobiTaklamakanMap.jpg
The Gobi Desert lies in the territory of the People's Republic of China and Mongolia.
Length1,500 km (930 mi)
Width800 km (500 mi)
Area1,295,000 km2 (500,000 sq mi)
Naming
Native nameГовь
戈壁 (沙漠)
Gēbì (shāmò)
Geography
CountriesChina and Mongolia
RegionInner Mongolia
Coordinates42.59°N 103.43°E

The Gobi Desert (/ˈɡbi/) is a large desert or brushland region in Asia. It covers parts of Northern and Northeastern China and of Southern Mongolia. The desert basins of the Gobi are bounded by the Altai Mountains and the grasslands and steppes of Mongolia on the north, by the Taklamakan Desert to the west, by the Hexi Corridor and Tibetan Plateau to the southwest and by the North China Plain to the southeast. The Gobi is notable in history as the location of several important cities along the Silk Road

The Gobi is a rain shadow desert, formed by the Tibetan Plateau blocking precipitation from the Indian Ocean reaching the Gobi territory. 

Geography

The Gobi measures over 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). It occupies an arc of land 1,295,000 km2 (500,000 sq mi) in area as of 2007; it is the sixth-largest desert in the world and Asia's 2nd largest. Much of the Gobi is not sandy but has exposed bare rock. 

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.

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.

Climate

 
Sand dunes in Inner Mongolia Autonomous Region, China
 
A summer monsoon produces a flash flood, 2004
 
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 metres (2,990–4,990 ft) above sea level, which contributes to its low temperatures. An average of approximately 194 millimetres (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, combined with rapid changes of temperature of as much as 35 °C (63 °F). These can occur not only seasonally but within 24 hours. 

Temperature

Sivantse (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 sandstorms 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 9 inches in length, were uncovered in 1923.

Despite the harsh conditions, these deserts and the surrounding regions sustain many animals, including black-tailed gazelles, marbled polecats, wild Bactrian camels, Mongolian wild ass and sandplovers. They are occasionally visited by snow leopards, brown 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 at an alarming rate 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 have increased in frequency in the past 20 years, causing further damage to China's agriculture economy.

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. It is part of the broader consequences of anthropogenic climate change, but locally driven by deforestation, overgrazing, and depletion of water resources. China has tried various plans to slow the expansion of the desert, which have met with some small degree of success, but no major effects. The most recent project is called the Three-North Shelter Forest Program which features huge strips of newly planted trees, in hopes that the baby trees will live long enough to establish a forest ecosystem which would stabilize the soil, retain moisture, and act as a buffer against further desertification. Most of the trees planted have died.

The Three-North Shelter Forest Program (or "Green Great Wall") was 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. From 1978 to about 2004, the survival rate for trees planted as part of the Three Norths Shelter Forest System Project was low (about 15%).

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

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 to 1,000 m (3,000 to 3,300 ft) above sea-level. Farther 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 salt 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 Takla Makan 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 to produce the correct, slightly hazelnut-like flavour of camel airag (fermented milk).

This great desert country of Gobi is crossed 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

The southwestern portion of the Gobi, known also as the Hsi-tau 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 saldgine 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 chequered network of hills and broken ranges going up 300 m higher. 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, Henderson's 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.

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 these chequered 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.

In 91° east, while 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 relatively favoured spots, is of the scantiest and is mainly confined to bushes of saxaul (Haloxylon), anabasis, reeds (kamish), tamarisks, poplars, and Ephedra.

European exploration

The Gobi had a long history of human habitation, mostly by nomadic peoples. By the early 20th century, the region was under the nominal control of Manchu-China, and inhabited mostly by Mongols, Uyghurs, and Kazakhs. The Gobi Desert as a whole was known only very imperfectly to outsiders, and information was confined to observations by individual travellers from their respective itineraries across the desert. Among the European explorers who contributed to the understanding of the Gobi, the most important were the following:

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