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近20年来,山于新技术的应用以及有关学科的相互渗透,第四纪气候演变的原因和机制已经得到了比较合理的解释.现代气候研究表叨,大气组成变化对于第四纪气候的发展演变以及将来气候的发展趋向有着相当重要的作用.大气组成的变化足以引起气候变化.6亿年前,大气中氧的含量仅占1%,而现在已达21%左右,这种氧含量的增加可以影响到CO_2含量的变化.除CO_2外,其他一些气体,如甲烷、氟化烃以及含氯氟烃等的含量变化都对气候变化产生作用,此即所谓“温室效应”对气候变化的影响.大气中CO_2的含量总体较少,目前仅占大气含量的0.03%,但它对于气候的影响却非常显著,据南极“多姆C”冰岩心研究成果,3万年来大气中CO_2含量曾出现过几次高值和低值.距今1.8万年前的末次冰期盛冰期前后数千年中,CO_2含量的平均值为200ppmv,全新世中平均约270ppmv,而距今7千年前的全新世新高温期中CO_2含量可能已超过300ppmv.直到工业革命之前,大气中的CO_2含量仍按近全新世时期大气CO_2含量的平均值270—290ppmv.
In the past 20 years, the application of new technologies in mountainous areas and the mutual infiltration of relevant disciplines has given a reasonably reasonable explanation for the causes and mechanisms of Quaternary climatic evolution.Characteristics of modern climate studies, changes in atmospheric composition, and the development of Quaternary climate Evolution and climate trends in the future plays a very important role.Changes in atmospheric composition is sufficient to cause climate change.Hundred 600 million years ago, the atmospheric oxygen content accounted for only 1%, and now has reached 21%, the oxygen content of Increase can affect the CO 2 content changes.In addition to CO 2, some other gases, such as methane, fluorinated hydrocarbons and chlorofluorocarbons and other content changes have a role in climate change, the so-called “greenhouse effect” on climate change The CO 2 content in the atmosphere is relatively low at present, accounting for only 0.03% of the atmospheric content at present, but its influence on the climate is very significant. According to the research results of the “Duomu C” ice core in the Antarctic, the content of CO 2 in the atmosphere over 30,000 years A few high and low occurrences occurred over the last ice age of 18,000 years before and after the ice age, the average content of CO_2 was 200ppmv around the mid-Holocene average of about 270ppmv, and 7,000 years ago, The new high-temperature period CO_2 content may have been more than 300ppmv. Until the Industrial Revolution, CO_2 in the atmosphere near the average 270-290ppmv CO_2 based upon the content of the Holocene atmosphere.