The Tuwaiq escarpment is a region of 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, 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. 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.
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:
Calligonum crinitum on dune slopes
Cornulaca arabica
Salsola stocksii
Cyperus conglomeratus
Other widespread species are:
Dipterygium glaucum
Limeum arabicum
Zygophyllum mandavillei.
Very few trees are found except at the outer margin. Other species are a woody perennial Calligonum comosum, and annual herbs such as Danthonia forskallii. The Asiatic cheetah and 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, and the driest areas can receive between 30 and of annual rain. Such dryness remains rare throughout the desert, however. There are few areas in the Arabian Desert, in contrast with the Sahara Desert, where more than half of the area is hyperarid. The sunshine duration in the Arabian Desert is very high by global standards, between 2,900 hours and 3,600 hours, but it is typically around 3,400 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 at low elevations, and can even soar to at extremely low elevations, especially along the Persian Gulf near sea level. Average low temperatures in summer remain high, over and sometimes over in the southernmost regions. Record high temperatures are above 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, 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. 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.
Overgrazing by camels and goats, with increased herd size, and a more sedentary lifestyle amongst the Bedouin
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.
Gulf wars
In January 1991 during the Gulf War, Iraqi forces released about 1.7 million m³ 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 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 of oil into the desert and formed lakes. All this damage was done to impede Coalition forces. Just before the 2003 Iraq War, they also set fire to various oil fields.