Document Type : Research Paper

Authors

1 Member of Faculty, Department of Geography, University of Isfahan (Translator)

2 Master of Geography, University of Isfahan (Translator)

Abstract

This paper summarizes the changes in gas reaction and climate tracing in the Holocene period (about 10,000 years ago), with respect to the four glacier periods of the past. The industrial era, which usually begins in the 18th century, is associated with increase in atmospheric greenhouse gases as a result of fossil fuels and land use changes, and these are linked to an increase in the average temperature of the earth's surface during the last decade of the twenty-first century. However, the analyses carried out by Ruddiman, which take the Holocene era and the urban community into consideration, have unprecedentedly compared changes in atmospheric greenhouse gases with that of glacial records of the past four hundred thousand years. During this period, carbon dioxide (CO 2) and methane (CH4) have increased, and this increase is probably due to the beginning of agricultural activities and land clearing in Eurasia. These and other changes in land use resulting from agricultural and rural activities may cause poor climatic change and prevent land’s temperature fall, or maybe due to natural forces. Although the early evidence supports the theory of Ruddiman, forestry and agricultural activities during the period of urban community may have exerted an impact on the climate equal to at least eight thousand years of the past.

Keywords

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