Glacial Problems in China (A General Review) (1)

Abstract

Recent geographical research in China has, as are exemplified by many articles in Acta Geographica Sinica of recent years, been carried out placing the emphasis upon the studies of natural environment, particularly of climatic factors, of the China's land and of its applied problems. This makes a remarkable contrast with researches before the war, when the majority of topics were concentrated on the problems of historical geography of the land. This change has been probably brought about in many cases in accordance with the national needs of China after “liberation”. Several major problems in which many Chinese geographers are interested can be drawn out from recent articles and publications of geographical research and among them are the glacial problems, past and present.
1) Glacial problems of China were originally discussed mainly by European geographers and geologists concerning the mountainous region of western China and several distinguished views were presented. However, after the war the situation of research has changed. The summary of geographic achievements and the present situation of European geographers and geologists are well expressed by H. von Wissmann in his illustration (Fig. 1) and the following statement.
“In Europa und Nordamerika kann man vielleicht zu Recht von einer pleistozanen ' oder eiszeitlichen ' Schneegrenzdepression sprechen. In Hoch-und Ostasien muss man die letzteiszeitliche Schneegrenzdepression streng von den Schneegrenzdepressionen älterer Eiszeiten auseinanderhalten. Für diese älteren Eiszeiten erscheinen die Unterlagen für eine Zusammenschau noch durchaus nicht zu genügen, zumal wir seit 1949 zu meinem grossen Leidwesen von der chinesischen Wissenschaft noch stärker geschieden sind als von der russischen.” (Die heutige Vergletscherung und Schneegrenze in Hochasien. 1959, s. 227)
2) There appeared several articles in Acta Geographica Sinica and Geologica Sinica of recent years dealing with the problems of glaciation and glacial ages of western China. By tracing remnants of glaciation in the Himalaya (around Mt. Everest), the Tien-Shan and the Chilien Mountains and the Tibetan Plateau, some different views are expressed concerning the ice ages of the past. For instance, some claim the existence of 4 ages, others 3 ages, still others 2 ages, and the last one seems to be the safest conclusion in the present condition of evidences.
Discussions have been concentrated on the relationship between climatic changes during the Pleistocene and the recent crustal movement continued in the mountain zones of western China. The conclusion common to many articles is that the combined effect has contributed much to the development of ice ages and extent of ice-cover. While many geographers agree that the younger the ice ages, the smaller the extent of glacial development (Fig. 2), despite the continual upheaval of mountain lands and that it proves the continual weakening of the invasion of oceanic influences from the Indian Ocean.
3) Remarkable theories were suggested concerning the depression of snowline of the past. A great depression, far greater than estimated by European geographers is assumed (Fig. 3), but the ice age in which such a depression occurred is still obscure. Some hold that it occurred during Qii period -the greatest ice age of the past-, while the other suggests the probability during the last the age.
As to the extent of ice-cover, two opposing views are presented, the one suggests a large extension which covered almost all the land higher than 4, 200 m, while the other claims the different degree of extension according to the patterns of ice-cover, which were determined by both topographical and climatic conditions of the region (Fig. 4).