Nagqu falls within the sub-frigid zone and experiences extreme cold, a scarcity of oxygen, dry air and storms. There are no absolutely frost-free periods. Nagqu has an annual average temperature of -0.9oC to -3.3oC, an annual relative humidity of 48-51 percent, an annual precipitation of 380mm, and he sun shines for 2,852.6-2,881.7 hours each year. From November to March the air is dry, the temperature low and the area is exposed to violent sandstorm. From May to September, Nagqu is warm and enjoys good weather. The annual growing season lasts for 100 days, and during this period the area receives 80 percent of its annual precipitation. At this time the grasslands are emerald and grazed by flocks of sheep.