Institute of biophysics, Siberian branch of Russian Academy of Sciences, Krasnoyarsk, Russia

bartsev@yandex.ru
lulja@yandex.ru
andong.china@gmail.com

Abstract. To date, the key issue for the development of civilization and improvement of quality of life is to assess the ability of the biosphere to neutralize anthropogenic СО₂ emissions caused by energy produced with heat engines. From a practical point of view, it is important to know not the most likely scenario of the biosphere evolution, which is the aim most of the most simulations of the biosphere, but the possible (within the confidence intervals) worst-case scenario for biosphere evolution. In this paper we used small-sized model of the biosphere to construct worst-case scenarios of the biosphere dynamics with different rates of fossil fuels burning. The model describes the global carbon cycle, which is assumed to be closed before the start of anthropogenic emissions and takes into account the positive feedbacks that exist in the "biosphere-climate". An additional amount of carbon entering the atmosphere by burning fossil fuels causes surface temperature increase due to the greenhouse effect. Various alternatives of the dynamics of the biosphere corresponding to the different rates of fossil fuels burning were considered. It is shown that the relevant provision of the minimum quality of life, based on the existing technologies of energy supply associates with a significant risk of irreversible catastrophic processes that can make future existence of life on the Earth questionable.

Key words: small-sized biosphere model, quality of life, global carbon cycle.