Kiro Miyazaki An Explanation of Global Warming without Supercomputing (399K, pdf) ABSTRACT. A new analytic solution of the radiative transfer equation is proposed. It is an extension of the semi-gray model developed by Weaver and Ramanathan. We consider the two parts of thermal spectra independently. In the first the infrared absorption (or radiation) is only due to water vapor. In the second both water vapor and carbon dioxide are active. The pre-industrial values of the corresponding two optical depths are determined so as to reproduce the global average temperature and the infrared spectrum observed by satellite spectrometer. Then, their post-industrial values are calculated on the assumption that the optical depth of carbon dioxide is proportional to its concentration but the optical depth of water vapor is fixed. As a result we can reproduce the climate change after 1850 fairly well. It is also found that the climate sensitivity never exceeds 6C. Consequently, the anthropogenic global warming is severely limited because the Earth is a planet of water.