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The Badain Jaran Desert is a desert in China which spans the provinces of Gansu, Ningxia and Inner Mongolia. It covers an area of 49,000 sq. kilometers (19,000 sq. miles). By size is labeled as the third biggest desert in China

This desert is home to some of the tallest stationary dunes on Earth. Some of the dunes reach a height of 500 meters (1,600 ft.) although most average at about 200 meters. Its tallest dune is also labeled by base to peak as the world's third largest tallest dune and highest stationary dune in the world

The desert also features over 100 spring-fed lakes that lie between the dunes, some of which are fresh while others are extremely saline. These lakes give the desert its name which is Mongolian for "mysterious lakes". It is also crossed by one river, the Ruo Shui ("weak water"), which has formed a great alluvial plain in the desert.

Geography
Measuring over 49000sq kilometers, the Badain Jaran Desert covers a significant part of the south-central part of the Inner Mongolia Autonomous Region as well as the North part of Gansu province. Located in the Alxa Plateau at about 1200 meters above sea level it is listed as a subsection to the Gobi Desert. It is bound to the north by the Gobi Desert and to the East by Mount Lang which seperates it from the Ulan Buh Desert (Pinyin: wū lán bù hé shā mò Chinese: 乌兰布和沙漠)

Although most of the dunes in the desert are not stationary, the larger ones usually ranging above 200 meters are static. With these dunes only the shallow surface of the sand is constantly shifting. The middle and lower layers of the highest dunes have been compacted for more than 20,000 years causing the sand particles to harden resulting in solid layers of sand and sandstone. High moisture levels inside the dunes also contribute to maintain their fixed state. This rigid structure also allows peaks, cliffs, gullies and even caves to form as a result of water erosion and desertification.

The Badain Jaran Desert, like the Tengger Desert which lies to the east (and with which the Badain Jaran Desert is currently merging with, due to extensive desertification in the area) is about one-half barren, sandy desert and one-half a mixture of solid bedrock and loose gravel. Several small lakes and Oasis' scatter the desert around which limited vegetation is able to grow.

Lakes
The Badain Jaran Desert is well known for its numerous scattered and colorful lakes. Containing more than 140 lakes they are mainly found in southern region in the desert. These lakes can easily be found in the larger valleys between large dunes. They are believed to provide the life sustenance in the desert supporting camels, goats and horses which are herded by nomads that travel through the desert. Most lakes also support a green ring of vegetation that populate the close vicinity around the lakes.

Due to large population of Algae, Brine shrimp and mineral formations, it causes some lakes throughout the desert to change color according to the time of year. Evaporation can also allow others to turn into hypersaline forming a salt crust around the rim of the lake.

Although their true sources are still debated it is believed that they are being maintained by underground water streams. Most arid deserts in China are surrounded by mountains that provide water sources, and this is the case with the Badain Jaran Desert. Runoff from the mountains is then collected through gravel deposits and this allows them to run through the desert, providing water sources for the scattered oasis's.

Within the desert there can be two main types of lakes found regarding their morphometry. The largely elongated shallow lakes mainly appear in the megadune area in the southeastern margin of the desert. Their depth often reaches less than 2 meters and only measure in about .2 square kilometers. The oval-shaped, deep lakes can also be found in the compound transverse megadune area. Their maximum depth reaches around 15 meters and attain a maximum size of around 1.5 square kilometers. The lake water can be extremely saline. The shallow lakes in the southeastern region of the desert tend to have low salt concentration, averaging at less than 20 g/L. Other lakes can show higher salt concentrations going up to more than 330 g/L.

Singing Dunes
The Badain Jaran megadunes is also one of the few places where a phenomenon known as the "singing sand dunes", "whistling sands" or "Booming Dunes". This rare occasion emits a sharp, loud noise that can be maintained for more than a minute. Although it is not widely understood it is believed that it is caused by an electrostatic charge that is generated as wind pulls the top layers of sand down a dune slope. This will produce a low pitched rumble that can reach over 105 decibels. The singing dunes will manifest itself by initiating an avalanche of sand down the leeward face of a large dune. This phenomenon however, does require very specific circumstances in order to generate the sound. They are silent throughout Winter when the humidity is being retained in the sand. In the Summer however, the booming can be generated but only on a slope of at least 30 degrees or more, on the leeward face of a dune, and the same sand on the shallow windward side cannot generate any noise. This phenomenon is only shared by around 35 other beaches and deserts around the world.

Under the same circumstances, it is also possible to generate another acoustic phenomenon. By moving a hand gently through the dry sand of a booming sand dune, this will shear the upper layer of sand off the slope and generate a burping emission (pulse-like, short bursts of sound).

Dunes
The Badain Jaran Desert is made up of hundreds of dunes ranging from small to large. Most of the megadunes in the desert average at about 400 meters from the base while most the rest average at around 200 meters. Out of all the megadunes, the Bilutu Peak (bì lǔ tú fēng) is the the most famous. It towers at 500 meters from the base and is the tallest dune in Asia (third tallest in the world). Unlike most of the smaller dunes the Bilutu Peak is stationary which makes it the world's tallest stationary dune.

While the larger megadunes are stationary (with only the top layer of sand shifting), the smaller dunes are constantly shifting according to wind patterns. This makes desertification a problem in surrounding areas as the desert is constantly expanding.

Climate
For tourists willing to go more out of their way, the Badain Jaran desert is definetely a popular tourist attraction. Based upon weather patterns, temperature and sight-seeing possibilities the best time to go is between June and October. Since the Badain Jaran Desert falls under temperate arid and extremely arid climate zones, it is important to be prepared when traveling through the dunes. The average annual rainfall is only between 50-60mm and is mainly centered between June to August. However the precipitation evaporation is between 40-80 times than that of rainfall. Besides the fact that it is much colder, Winter and Spring have very strong winds coming mainly from the northwest getting to more than 60 days long. These winds can even get up to wind force 8. Due to these aspects of the desert climate, the popular tourist time is based upon when the climate is most comfortable. Appropriate foot wear should be worn though due to the fact that sand temperatures can exceed 80°C.

Badain Jaran Temple
The Badain Jaran Temple (bā dān jí lín miào 巴丹吉林庙)is a well preserved Tibetan-buddhist temple located in the middle of the desert. It was build in 1868 at the side of a like. Its isolation allowed it to survive untouched and safe from the Cultural Revolution. The fine state of preservation allows you to visit its 300 square meters of statues, wood carving, artifacts and a small, white pagoda.

It is only accessible by traveling through the desert. The most common method to reach the temple is to rent a sand jeep at the local tourist center located along the S317. To reach the temple the process is to choose a driver, tell him the main sites you would like to visit and how many days (they are payed per day). The jeeps are simple 4X4 military jeep with reinforced frames and deflated tires. These jeeps will drive over the sand dunes for several hours to take you to the temple while stopping several times at lakes, scenic spots as well at the Bilutu Peak.

Bilutu Peak
The Bilutu is also a location which is commonly accessed using the sand jeeps. It is the world's highest stationary dune rising over 500 meters and peaks at 1609 meters above sea level. The surrounding dunes only reach about 200 meters. Although the biggest, it is one of several large stationary dunes within the Badain Jaran Desert. Upon reaching the top there will be a clear view of the surrounding dunes as well as several colorful lakes.

Khara Khoto
Also known as the ancient black city, it is located in the northwestern side of the desert near the Ruo Shui River and is located fairly close to the new city of Ejin. The ancient city was a Tangut city founded in 1302 which became the center of the Tangut empire. When Genghis Khan conquered the city it flourished again under Mongol rule. However, the city fell to Chinese armies in 1372 during the Ming dynasty and was left abandoned and in ruins. It has been untouched since. Although not accessible using the same jeeps, it is possible to find transport in the city of Ejin.

Mt. Mandela Rock Paintings
http://www.china.org.cn/english/China/218226.htm