Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The Quaternary is marked by the Great Ice Age. The basic characteristics of this great ice age are the alternating of glacialinterglacial period in orbital scale and changes of stadial-interstadial in suborbital scale. Present is a relatively warm interglacial period, with glaciers covering only 10% of the land area. At the glacial maximum, glaciers covered about 30% of the global land area, permafrost spread, climate was dry with prevalence of dust, sea level reduced 130–150 m, vegetation contracted to low latitudes more than 10°, and the vertical band spectrum moved down more than 1 000 m. The astronomic theory of ice ages has successfully explained the glacial-interglacial cycles, however, there are still a lot of problems to need studies in detail. Quaternary is also the period of ancient human development. Ancient human was born in East Africa and spread to Eurasia only on a limited scale about 2 Ma ago. The spread on a large scale started during the last interglacial and spread to America and Australia by means of land bridges during Last Glaciation Maximum (LGM). After the younger Dryas, the climate became warm and the human entered the Neolithic Period and gradually transited to the agricultural society. After the Industrial Revolution, human development has been profoundly affecting the natural process of the Earth, leading to global warming, heralding the arrival of an “Anthropocene”.
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