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第四纪研究 2002
NONGLACIAL ABRUPT CLIMATE CHANGE AND SOLAR VARIATION
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Abstract:
Progress in the study on the abrupt climate changes occurring in the nonglacial period, namely the Holocene, has been introduced. Occurrence of the abrupt climate changes during the Holocene implies that there is a new mechanism of climate forcing which is different from the glacial scale climatic variations. However, more pieces of evidence have shown that solar activity may play an important role on the climate variation during the Holocene. This review briefly introduced the research history of 14 C tree ring as a proxy indicator of solar activity. In recently Gerard Bond et al have made comparison between the drift ice indices of the North Atlantic and the proxy indicator time series of solar activity. They suggest that the Arctic Nordic Seas may have been a key region where solar induced atmospheric changes were amplified and transmitted globally through their impact on sea ice and North Atlantic thermohaline overturning. Moreover, reduced northward heat transport could have further altered North Atlantic latitudinal temperature and hydrologic gradients, potentially enhancing the climate response in low latitude climates. As Gerard Bond et al have pointed out that more lines of evidence have shown that Earth′s climate system is highly sensitive to extremely weak perturbations in the Sun′s energy output. The influence of solar variation on the climate change during the Holocene seems to be convincing.$$$$