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在温带泥炭湿地上,泥炭的增长被认为是整个晚显生宙主要的气候调控机制之一。自从植物生命开始在陆地上出现以后,泥炭湿地一直是显著的陆地碳汇,它可以为沉积物和冰岩芯等观察到的大气组成的变化提供较好的解释。由于碳的汇过程形成了无烟煤、褐煤和泥炭,它们都是在相同的条件下形成的。泥炭的增长和分解被认为是与晚新生代冰期和间冰期有规律的转换有一定关系,这为Milankovitch理论提供了另一种解释。人们认为冰期将景观转换为适宜于泥炭地开始发育的类型,因此形成了一个反馈机制系统。我们的模型表明,将来在没有人类产生温室气体(如CO_2)排放的自然条件下,考虑到海洋的调节作用,在不到1000年的时间里可能出现一个新的冰期。如果像目前这样温室气体浓度不断增加的情况下,冰期开始时间将很可能会随大气浓度增加而相应地推迟。在目前的CO_2水平(大约350ppm)下,我们的模型表明,新冰期开始出现时间可能至少被延迟700～1000年。在最坏的方案中,即CO_2排放不断增加、人类活动一直不停地排放CO_2直到公元2500年,在我们模型中的多数情况下,冰期开始出现的时间将至少被推迟1万年。
On temperate peat wetlands, peat growth is considered as one of the major climate regulation mechanisms throughout the Late Phanerozoic. Since plant life began to appear on land, peat wetlands have been significant terrestrial carbon sinks that provide a good explanation for the observed changes in atmospheric composition of sediments and ice cores. Anthracite, lignite and peat were formed as a result of carbon sinks, all formed under the same conditions. The growth and decomposition of peat are thought to be related to the regular conversion of the Late Pleistocene glacial and interglacial periods, which provides another explanation for Milankovitch’s theory. It is believed that the glacial phase transformed the landscape into a type suitable for the beginning of development in the peatlands, thus forming a system of feedback mechanisms. Our model shows that in the future, under the natural conditions of human emissions of greenhouse gases (such as CO 2), a new ice age may emerge in less than 1,000 years, taking into account the regulatory role of the oceans. If, as is currently the case, the concentration of greenhouse gases continues to increase, the start of the glacial period will most likely be postponed as the atmospheric concentration increases. At current CO 2 levels (around 350 ppm), our model shows that the beginning of the onset of the new glaciation may be delayed by at least 700-1000 years. In the worst scenario, where CO 2 emissions continue to increase, anthropogenic activities continue to emit CO 2 until the year 2500, and in most of our model, the onset of the glacial phase will be delayed by at least 10,000 years.