Within the analysis of scientific background of the Kyoto Protocol, the following issues are considered:
- what is the possible accuracy of determination of annual average global temperature using currently available observation tools of the global network?
- what kind of fluctuations can global temperature undergo if not subjected to any anthropogenic factor?
- what is the relation between global temperature changes caused by observed changes in atmospheric greenhouses gases and the natural stochastic variability of global temperature?
It is demonstrated that (i) the poor coverage of the globe by surface temperature measurements hinders reliable detection of long-term changes in global temperature values at a level of 0.4 K per century or higher; (ii) stochastic factors of global temperature variability give rise to random trends at a level of 0.4 K per century or higher with a high possibility; (iii) an energy equivalent of the stochastic factors of global temperature variability no less than by an order of magnitude exceeds that of the anthropogenic contribution caused by greenhouse gases emission to the Earth's energy balance; (iiii) carbon dioxide increase in the atmosphere is not a cause, but rather a result of the global temperature growth, which, in turn, results either from purely random variations in the factors governing the Earth's radiation balance or from long-term variation of the global temperature index.