The Gobi Desert is the largest desert region located in Asia, spanning the north / north-western part of China and the south of Mongolia. The desert is surrounded by the Altai Mountains and the grasslands of Mongolia. It is the fifth largest desert in the world. The temperatures in the Gobi Desert fluctuate rapidly. It can go from being 25 degrees F to -30 degrees F within a few days. The temperatures can go as high as 122 degrees F and as low as -40 degrees F.