The Climate of the Gongga Shan Range, Sichuan Province, PR China

Abstract

Gongga Shan (Tibetan: Minya Gongkar, alt. 7556 m) is located west of the Sichuan Basin bordering the Tibetan Plateau. It is the highest mountain in China, excluding Himalayan summits in Tibet. The eastern slopes reach down into the Dadu Valley (1100 m) and are colder and more humid at comparable altitudes than the western slopes which blend into the Tibetan Plateau (3000 to 3500 m). Maximum precipitation along the east slope occurs at 2900 to 3200 m at far higher altitudes than in other Chinese mountain ranges. Due to the combination of high evaporation rates at low altitudes and generally increasing precipitation with altitude, high-altitude belts with humid conditions have developed above arid valley zones.

Climatic differences between east and west slopes cannot be explained only by exposure. Located at the northern end of the climatic transition zone between southwest and southeast monsoonal air masses, the orographic barrier of the Gongga Shan range is thought to anchor the climatic boundary which farther south moves about 400 km seasonally in an east/west direction. Differences in winter climatic conditions and summer precipitation patterns between both sides of the range support this assumption.