摘要
资料分析和数值模拟均表明，青藏高原作为一个特殊的抬高了的下垫面，其上雪盖面积和积雪日数等的异常均与亚洲夏季风的强弱及起讫有关．雪盖面积大、积雪日数多的年份，亚洲季风弱且爆发迟，推进慢；雪盖面积小、积雪日数少的年份，亚洲季风强且爆发早，推进快．
Impact of snow cover on climate in large scale is a major project in the earth sciences. Data analysis and numerical simulations show that the anomalies of snow cover area and the duration of snow accumulation on the Tibetan Plateau, an uplifted surface, are related to the strength, the beginning and the end of the Asian summer monsoon. If the snow cover area is large and the duration of the snow accumulation is long, then Asian monsoon occurs later and advances slowly. In such a year, Asian monsoon is weak. If the snow cover area is small and the duration of the snow accumulation is short, then Asian monsoon is strong and occurs early and advances quickly. It seemed easy to understand on the physical aspect that there exists correlationship between the snow cover on the plateau and the Asian summer monsoon precipitation, because snow cover is one of the important physical factors that affects the underlying surface condition and the air heat condition. It is well known that the monsoon relates to the heat conditions of the underlying surface. So it is certain that the snow cover anomaly would affect the summer monsoon activities. There are also some other opinions that are not accord with the above results. The study results reported by Li Peiji show that the variations of the Indian summer monsoon precipitation are not mainly caused by the anomalies of the snow cover on the plateau. The snow cover on the plateau in pre-winter does not have the so-called significant correlationship with the Indian summer monsoon precipitation in post-summer. Therefore, the relationship between the snow cover on the plateau and the strength of Asian summer monsoon and its corresponding precipitation belt is still an unresolved problem. It is necessary to cumulate quality snow cover data and to enhance the understanding of the monsoon and its corresponding precipitaiton belt.
出处
《冰川冻土》
CSCD
北大核心
1998年第2期186-191,共6页
Journal of Glaciology and Geocryology
基金
中国科学院重大项目
关键词
青藏高原
雪盖
亚洲季风
季风
Tibetan Plateau, snow cover, Asian monsoon
