The Gobi Desert  is a large desert or brushland region in East 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. It is the sixth largest desert in the world and the second largest in Asia after the Arabian Desert.

The Gobi measures over 1,600 km (1,000 mi) from southwest to northeast and 800 km (500 mi) from north to south. It is the sixth-largest desert in the world and Asia's second 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.

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

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 approximately 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, combined with rapid changes of temperature of as much as 35 °C (63 °F). These can occur not only seasonally but within 24 hours.

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).

The Gobi Desert is the source of many important fossils finds, including the first dinosaur eggs, twenty-six of which, averaging 9 inches (23 cm) 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, 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 have increased in frequency in the past 20 years, 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  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.