Before the Qinghai?Xizang Plateau is uplifted or during it is uplifted up to the critical height, about 2 km ASL, the sea level pressure, 500 hPa and 100 hPa level heights are all lower than they are now all over the most part of the Northern Hemisphere.

• 高原隆升前和隆升至临界高度时,北半球绝大部分地区海平面气压场、500hPa高度场、100hPa高度场都比现在偏低。