Table 4.

Comparisons of regional characteristics of lowland and highland area.

Characteristics	Lowland	Highland
Location	Southeast of Zhejiang Province, China. Lowland area.	Northwestern of Sichuan Province, Tibetan Plateau in Southwest China.
Altitude	10 meters.	More than 3,300 meters.
Climate	Central Asian tropical monsoon climate zone, with four distinct seasons and abundant rainfall.	Continental plateau monsoon type. No summer. Frost and snow occur in fourth seasons, and the atmospheric oxygen content is <60% of the standard.
Sunshine	Annual sunshine between 1,442 and 2,264 h.	Average annual sunshine about 2,451.1 h.
Time of sunrise and sunset
Summer solstice	Sunrise at 5:01 sunset at 18:56.	Sunrise at 6:12 sunset at 20:28.
Winter solstice	Sunrise at 6:44 sunset at 17:06.	Sunrise at 8:16 sunset at 18:18.
Temperature	Annual average temperature is 17.3–19.4°C. Average temperature in January is 4.9–9.9°C. Average temperature in July is 26.7–29.6°C.	Annual average temperature is −0.16°C. Average temperature in January is −11.1°C. Average temperature in July is 9.9°C.
Rainfall	Annual precipitation between 1,113 and 2,494 mm. Raining season comes at the end of spring and early summer. Tropical cyclone happens between July and September. Frost-free period is 241–232 days.	Average precipitation 65.4 mm, and mostly happens during June to September. Average frost-free period is 21 days. Areas with higher altitude has no absolute frost-free period.