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What Humans Contribute to Atmospheric CO2: Comparison of Carbon Cycle Models with Observations

The Intergovernmental Panel on Climate Change assumes that the inclining atmospheric CO2 concentration over recent years was almost exclusively determined by anthropogenic emissions, and this increase is made responsible for the rising temperature over the Industrial Era. Due to the far reaching consequences of this assertion, in this contribution we critically scrutinize different carbon cycle models and compare them with observations. We further contrast them with an alternative concept, which also includes temperature dependent natural emission and absorption with an uptake rate scaling proportional with the CO2 concentration. We show that this approach is in agreement with all observations, and under this premise not really human activities are responsible for the observed CO2 increase and the expected temperature rise in the atmosphere, but just opposite the temperature itself dominantly controls the CO2 increase. Therefore, not CO2 but primarily native impacts are responsible for any observed climate changes.

Carbon Cycle, Atmospheric CO2 Concentration, CO2 Residence Time, Anthropogenic Emissions, Fossil Fuel Combustion, Land Use Change, Climate Change

APA Style

Hermann Harde. (2019). What Humans Contribute to Atmospheric CO2: Comparison of Carbon Cycle Models with Observations. Earth Sciences, 8(3), 139-159.

ACS Style

Hermann Harde. What Humans Contribute to Atmospheric CO2: Comparison of Carbon Cycle Models with Observations. Earth Sci. 2019, 8(3), 139-159. doi: 10.11648/

AMA Style

Hermann Harde. What Humans Contribute to Atmospheric CO2: Comparison of Carbon Cycle Models with Observations. Earth Sci. 2019;8(3):139-159. doi: 10.11648/

Copyright © 2019 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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