Tibet, the Roof of the World, is the highest plateau in the world. However, most of its land is arid or a semi-desert. The average annual precipitation is about 381 mm (about 15 inches) and is significantly less in some areas. Tibet experiences bitterly cold weather and is lashed by harsh winds throughout the year. The average annual temperature is around 1.1 degrees Celsius (34 degrees Fahrenheit).
The mountains are treeless, with only grasses and shrubs growing. Tibetan people live in the valleys of the Indus and the Brahmaputra, where they are able to grow some crops. The river valleys also support a few species of trees including oak, cypress, polar and maple. In addition, the people grow apple, peach, pear and apricot trees.
